The Musings of a Life-Long Scholar

a new (to me) sort of sample collecting

2012-01-26T07:13:00.001+11:00

Sample collecting. It is something that we geologists have all done. It isn't enough to look at rocks in the field, we need to bring them home too, if we want to answer the questions that come up in the field. My current job, however, doesn't yet have field work in the traditional sense. Instead my “field” is the collection of drill cores which have been amassed over years of exploration and mining in this district. I have just completed my first two “field” trips to look at this core, which is to say I have been introduced to the core storage shed at the mine headquarters. Last week and the week before I worked with one of the geologists in the exploration division of the mine office. We looked at four different drill cores to select representative samples at roughly 50 meter intervals to be sent away for geochemical analysis.

This is an interesting task—my project will involve 3D geochemical modelling with the aim of understanding the alteration that has happened to the rock in the region during the process of the formation of the ore deposit. Therefore we need to be certain the samples we choose have been altered, but that the alteration that has taken place in these rocks is related to the main alteration event of interest. Therefore we want to avoid the sections of drill core which contain small veins which cut across the fabric of the rock (which means that they formed well after the deformation that caused the main rock fabric, and so are younger, and so probably aren’t related to the question I am trying to investigate). Because my project will be on the kilometer scale we don’t want to take the samples too close together (hence the 50-meter interval rule of thumb), but then again there is value in making certain that we have a good representative collection of samples that actually show what rock types are present in each drill hole.

This is easier to do for some drill holes than others. You see, drill core comes in different diameters, based on a variety of factors when they do the drilling, but the boxes into which they store the core are fairly uniform in size. This means that one box will hold more meters of narrow core than it will wide core. We sampled 4 different drill holes over the two weeks I was there—the narrowest core tended to be 10 or 11 meters of core per box, but the widest one was less than 5 meters of core per box (the other two were about 7 meters each). The tables upon which we spread the boxes hold 10 boxes at a time, which means we could view 50, 70, or 100 meters of core at a time. Needless to say, it is much easier to decide what rock types are “typical” for a given stretch when we can see more of the core at once.

"Directly" experiencing Subduction-Zone processes

2011-12-30T23:11:00.005+11:00

I haven’t made time to participate in an Accretionary Wedge for a long time, so when Ron Schott called for the "Most Memorable/Significant Geologic Event That You’ve Directly Experienced", I thought it was about time to come out and play this game again.

In his call he gives some examples of a few processes that take place in human observable time frames and at surface pressures and temperatures (e.g. earthquake, landslide, flood…) and he repeats the part of his challenge about our being able to directly observe and experience the process we write about.

However, the sorts of geologic processes which most fascinate me are not those which create sediment at the surface of the earth, nor yet processes which produce fine-grained igneous rocks. To my eyes the most significant geologic processes are those which are responsible for creating the pretty rocks that drew me into geology in the first place—the ones with beautiful large crystals. Metamorphic processes, and also igneous processes when they take place deeply enough to permit significant crystal growth, are my favourite of all of the many geologic processes. However, the pressures and temperatures which are responsible for making particularly pretty rocks are well in excess of what our frail bodies can tolerate, which means that the process isn’t something I can ever "directly experience".

Or is it? How can we ever know what is happening within a subduction zone?

This question was not only of interest to me, but also to the international research team I joined when I began my last post-doc position. While none of us could go down the subduction zone ourselves to find out what was happening there, we were able to bring a tiny bit of the subduction zone setting into our lab.

Using a piston cylinder apparatus I regularly performed experiments which match the sorts of pressures and temperatures one would find if one could enter a subduction zone. While real rocks can spend millions of years working their way down a subduction zone and then back up again, I only held my samples at high pressure and temperature for two to four weeks at a time. As a result the crystals I grew from my powdered starting material did not achieve the large, stunningly pretty, sizes one can find in metamorphic rocks, but they did grow up to 100 µm in length (remember that there are 1000 microns in every millimetre), and many were lovely to look upon in the BSE images.

Having had the opportunity to perform such experiments I confirmed for myself that yes, pressure and temperature do matter to the minerals in a rock. If one takes the exact same starting material and "cooks" it at different settings one will get a different assemblage of minerals for each combination tried.

The below images show some of the results for one of the compositions I tested, at three different pressures (2.65, 2.8, and 3.0 GPa), and three different temperatures (600, 625, and 650° C). As you can see, the sets of phases present are very different for each experiment. Even the phases which are present in all experiments are present in different abundances when the pressure, temperature, or both are changed.

The few photos I have shared with you today are just a glimpse some of the experiments I have done. All of them together have transported my imagination to the depths of a subduction zone, and brought the merest hint of a subduction into my lab. This is "directly experienced"enough for me.

List of abbreviations:

grt = garnet

mu = muscovite (or other white mica)

qtz = quartz or coesite*

ctd = chloritoid

anth = anthophyllite

tlc = talc

*In all cases the SiO₂ phase is labelled "qtz", even when it is at pressure high enough for that phase to probably be coesite—the microprobe does not differ between those two phases, and I did not check it with another technique (such as Raman) because the difference between quartz and coesite wasn’t relevant to my work, which was focused on questions related to the stability fields of talc, biotite, and garnet.

Wish I had seen this one years ago

2011-12-29T22:59:00.001+11:00

Earlier this month I discovered that it is possible for me to download entire textbooks from the internet. Now, it may be that the reason I can do this is because I am on a university computer and they have an account with the publisher which makes it possible, but since a high percentage of readers who might be interested in the book I am about to talk to you about are likely to associated with a university in some capacity, there is a reasonable chance that you will have access to it as well, if not as a download, perhaps in paper at your uni library.

The book which I am enjoying reading just now is Phase Equilibria in Metamorphic Rocks, Thermodynamic Background and Petrological Applications, written by Thomas M. Will, published in 1998 by Springer, DOI: 10.1007/BFb0117723. This is volume #71 of a Lecture Notes in Earth Sciences series.

When I first started my PhD project in the field of metamorphic petrology I was coming into the field cold—it had been years since my last geology course of any sort, and I had had no background courses on topics like thermodynamics or the many calculations associated with phase equilibria. Consequently, when I started reading papers which included formulas that explained how the authors had arrived at their estimates for the pressure and temperatures at which their minerals formed I found myself skipping over the equations and looking for the sentences that explained what was done. Over time and after reading many papers which did this sort of thing I started to gain a partial understanding of the topic. Enough to apply the tools to my own samples and arrive at numbers that, hopefully, actually reflect the history of the samples.

However, while I could follow a recipe for calculating pressure and temperature of formation for metamorphic minerals, I choose which recipe to apply based on the fact that my samples were similar to those in the published papers, not because I had any real understanding of the models which underpinned the calculations. Terms like “ideal” vs “non-ideal” mixing painted pictures in my mind because I know what those words mean grammatically, not because I actually knew the difference between them as applied to the crystal structure of a mineral.

If you are in a similar boat, and would like to actually see good definitions of those terms, along with others like “entropy of mixing”, “activity-composition (or a - x)”, this may be the book for you. So far I have only managed to read the first 40 pages, but already I have a *much* better understanding of why it is that one gets such hugely different results in terms of pressure/temperature estimates depending on which model one uses for a given mineral, and a much better understanding why programs like Perple_X have so many models available to choose from. The author is kind enough to work through example calculations in a step-by-step basis, so that the reader can learn how it is done. Sure, when actually doing the geology you aren't going to do these calculations by hand—at the very least you will have a template full of formulas set up in a spread sheet, if not using a more complicated program to do the work for you, but it is always nice to understand *how* the program does the calculations—this makes it much easier to spot if a typo in the data-entry stage resulted in a geologically implausible answer being spit out by the program.

Science is the ultimate game for adults

2011-12-15T22:42:00.003+11:00

I have just come from listening to a lecture by Dan Shechtman, this year’s Nobel Laureate in chemistry. The topic of his speech was his 1982 discovery of quasi crystals which has led, all these years later, to his achieving a Nobel Prize for his work.

He began his talk with an introduction to the science of Crystallography, which was founded in 1912 when Sir William Lawrence Bragg and his father Sir William Henry Bragg first starting using X-rays to study the diffraction pattern caused by crystals. (Prior to that breakthrough people studying crystals measured the angles between the faces of crystals, which had been done at least as far back as the 1600’s—Johannes Kepler published studies of snowflake crystals in 1611, and in 1669 Nicolaus Steno reported consistent sets of characteristic angles for quartz crystals, no matter where the crystals came from.)

During the next 70 years crystallographers studied 1000’s of crystals using X-ray diffraction, and they all conformed to a set of rules which became accepted as the definition of a crystal:

*They all had a periodicity; if you measure from the center of the diffraction pattern to the first spot, and then move out again that distance in the same direction you will encounter another spot, and another again each time you repeat the pattern.

*they all had a rotation of symmetry; this means that if you rotate a crystal around an axis you will get a repeat of the same pattern every certain number of degrees. The possible amounts of rotation were 2, 3, 4, and 6.

This means that a crystal with a 2-fold rotational symmetry can be rotated half way around (180 degrees) and will look exactly the same as before it was rotated. A crystal with a 3-fold rotational symmetry can be rotated to three different positions (each 120 degrees apart) which have the exact same pattern. 4-fold means that each rotation is 90 degrees apart, and 6 fold is 60 degrees apart.

As Professor Shechtman emphasized in the early portion of his talk, this list was it—crystallographers knew that no other rotation symmetry pattern was possible. There was no such thing as a 5-fold rotational symmetry, nor were there any crystals with rotational symmetry greater than 6. This was so well accepted that when he was a student he once had an exam question requiring that he prove that 5-fold rotational symmetry was impossible.

He shared with us his answer on the projector screen. It works better with images, but I will try it with words alone (see this page for more details). Start with a dot on the center of your page, then put five dots around it in a ring, each 66 degrees apart, all the same distance from the center dot and from one another. If 5-fold rotational symmetry is possible one could then take any pair of those encircling dots, rotate around them in five steps, plotting a new circle of dots around each, and the new dots around one would line up with the new dots around the other. However, as he showed us on the screen, this does not happen—if you colour one set in blue and the other in red they clearly fall near, but not upon, one another.

Therefore when he noticed a crystal which showed a 10-fold axis of rotation on a transmission electron microscope on the afternoon of 8 April 1982 is was more than a bit surprised, as one can see with the triple question marks he wrote in his notebook. His first thought was that it must be the result of crystal twinning, which had been known to cause the appearance of five-fold rotational symmetry but was really the result of having more than one crystal contributing to the diffraction pattern. So he zoomed in to the limits of the machine and took the diffraction pattern again, several more times, and each time he received the same result—a 10-fold rotational pattern, and from areas so tiny that the possibility of there being more than one crystal contributing to the pattern had been eliminated.

How was this possible? Well, the substance he was studying does have a rotational symmetry that had previously thought to be impossible, but it achieves it by lacking in periodicity—the pattern does not repeat if you jump a set distance in a given direction. As a result of his discovery the definition of a crystal has changed to say “any solid having an essentially discrete diffraction diagram”. These days we call substances such as the one he discovered “quasicrystals” and it turns out that they are reasonably common. But in the early days after the publication of his discovery he met with much resistance to his ideas—one scientist was even heard to declare that there are no quasi-crystals, only quasi-scientists”. However, as happens with science, other laboratories repeated is results, both with the compound he first noticed the phenomena in, and then with other compounds, and gradually the acceptance spread throughout the scientific community.

After he finished his speech there was time for a few questions from the audience. One of the University faculty members ask him a question—she pointed out that this university, like many others, has difficulties attracting students to the study of science, and she wondered if he had any advice in how we might better convince young people to study science. His reply included one of the best quotes I have heard in ages “Science is the ultimate game for adults”.

I believe that he is, in fact, correct with that description—studying science is fun, it requires us to use both our logical and creative parts of our brains, and to push both to their limits. It provides enough challenge to prevent us from ever being bored, and it comes with possibility of making discoveries which change the way we view our world. What could be more fun than that?

Can’t make it to AGU this year? Neither can I, but I will still visit the poster session

2011-12-05T21:43:00.001+11:00

It is once again the time of the year for the big AGU conference in the US. I made it to the one two years ago, and found it kind of overwhelming in its hugeness, with talks and posters on any number of topics which fall into categories of which I know nothing, because geology is nothing if not a huge broad catch-all of a science. Fortunately for us that meeting, like many others these days, has a fully searchable program, permitting us to find those talks or posters we should hear/see because they relate to our own research, and those talks which are totally outside our current research but still fall into topics which are of personal interest. This year, in addition to having the computerized program, they have also made much of the poster session available on line. Therefore those of us who are staying home can still have the fun of wandering the crowed isles and looking at interesting research results. So ahead, go on over, look at some posters, and learn something new. Perhaps you will even find something interesting enough to send the author a note inviting conversation on the topic.

reading for fun and education

2011-12-02T23:51:00.001+11:00

Sixty days ago I received the job offer to start my new job, and was given a small pile of literature for background reading before I started. As a result I started my “1000 words a day” challenge once again, after having had nearly a year off since last I had done that. The challenge is simple: do a little reading in the geologic literature every day, and keep track of how many days in a row you manage before you miss one. If you miss one re-start and begin the count from zero once again. How much is 1000 words? Well, today’s post is 691 words long. It doesn’t take much time to read that many words, but I have found that if I read that many I often keep reading the article until I either reach a natural breaking point or finish the article. Some days I read quite a bit more, others I just barely make the goal (do I actually count the words? No, not any more. And when I did at the beginning of the first time I undertook the challenge I didn’t count all the words, just how many words were in the first line of a paragraph, and how many lines long it was to calculate a rough word count for the paragraph, and then figured out how many paragraphs of that size it would take to reach at least 1000 words. It isn’t the precision that matters, but the consistency of actually reading (and thinking about what you read!) every day.

Since I started this time I have remembered to read every day. This has been easy during the week days since my job begun—the pile of literature I need to read and understand in order to get my knowledge base to where it needs to be for my research project is quite substantial, and growing all of the time as I find references to more and more articles I wish to read. Managing it on the weekends is a bit more of a challenge, but I have managed, so far.

So, what have I read over the past 60 days? I have completed reading six articles that relate directly to the ore deposits in the area near where my project is based (ok, one of those wasn’t a single article, but rather a PhD thesis which was comprised of five different papers, so really I have done 10 articles total on this subject), four articles on the concept of 3D modelling, and one article on geochemistry.

That last one (MacLean 1990)* explains how one can use ratios of immobile elements to calculate what the unaltered composition of a suit of altered rocks must have been. I am gathering from my reading (many of those local papers cite this technique paper) that this is a very useful way to determine what types of rocks were present before the hydrothermal alteration associated with the formation of ore deposits. It works especially well when the precursor rocks are volcanic and changed in composition due to fractionation of the magma. When this is the case one can plot the current compositions on the same diagram as the curve which shows the expected changes in composition due to fractionation, and extrapolate from the trends in the current compositions back to the likely original compositions when the rocks cooled from their magma. The paper mentions that these sorts of calculations are easy to set up in a template in a spreadsheet, and that they will give away such templates upon request. I wonder if that offer is still open two decades after the paper was published, or if people use a different technique to accomplish the same sort of task today. I will have to do a search for papers which cite this one to work my way forward to the modern techniques, if they have changed. What did people do for research before it was possible to easily look up who had cited a particular paper?

*MacLean, W. H. (1990). "Mass change calculations in altered rock series." Mineralium Deposita 25(1): 44-49.

How I am spending my time

2011-11-30T23:55:00.001+11:00

I have mentioned previously that I keep a log of how I spend my time. When I was doing my PhD the interesting question was what percentage of my time was spent on “uni work”, and how was I spending the rest of my time? That way I could look at the graphs and easily decide what I should change if I wasn’t happy with my progress. I have maintained those logs since finishing that degree, and even made use of the data when applying for my visa to move to Sweden—the abrupt increase in the amount of time spent doing “social” activities when I met my partner was part of the documentation that we really do have a relationship with one another.

However, comparing “uni work” to all of the other aspects of my life is not the full story. This morning I was struck with the inspiration that I should also track what sorts of “uni work” I am doing. Since it has only been one month since I started my new job it seemed like a good time to set up the spreadsheet to calculate that, too. I have created five broad categories into which all of my “uni work” tasks fit. I then compared the data in my descriptive log of what tasks I accomplish each day (e.g. “revised figure 2.5 to show____”, or “received a copy of my hire paperwork from HR and filed in in folder ____”) with my numeric log showing how many hours in each day were spent on uni work, and have estimated the split for each day since this job began. In addition, I also calculated my time for most of October, since I did my job interview, began reading the literature my boss gave me as background reading for this project then, and attended two different short courses during that month.

Setting up the spread sheet and doing those estimates took all morning, but since that was 58 days’ worth of data that means that I spent less than 4 minutes a day on this project. Now that the spreadsheet is set up it should be even easier to keep it up to date by entering in the new data, and I think that I can easily spare 4 minutes a day for the return of seeing the distribution of how I am spending my time. This will be particularly useful as my boss told me that the teaching component of my work should only be 10 to 20% of my time, and this way I will know if I am falling under, meeting or exceeding this target.

The categories I chose are:

* Research: which has three sub categories, the first of which is my current job (3D geochemical modelling of ore deposits in northern Scandinavia), the second and third are finishing up the papers based on my PhD and last post-doc positions.

* Learn: reading literature, attending courses, attending conferences, talks, and seminars, studying Swedish, etc.

* Teach: teaching classes, teaching prep, meetings about teaching, etc.

* Admin: administrative tasks, filing, computer maintenance issues (install programs and hardware, backup, etc.), paperwork, work-related travel, funding applications, updating logs, cleaning/organizing the office, meetings on any of these sorts of topics, etc.

* Netwk: networking, updating resume, updating LinkedIn and Academia.edu, interviews, public outreach, job applications (when this contract draws to a close), etc.

For the month of October I worked a total of 82.6 hours (which all counts as bonus time, as my job had not yet started). Of that time 68% was spent on “learn”-related tasks, 31% was “admin”, and 1% was “netwk”. There is still nearly half a work day left for November, but the month is close enough to done to report that my time this month has been split roughly:

38.9% research (10.5% this job, 20.5% last job, and 7.9% PhD research)

31.5% admin

12.5% learn

17.1% netwrk

0% teach

Assuming 8 hour work days, no work on Sat or Sunday, and only 4 hours for the one Friday in November which was a half-day holiday I should have worked 172 hours on this job so far this year. However, because I started work-related tasks back in October I am already up to 233.4 hours, or 135.7% of the hours I need.

Combining the data for October and November gives:

32.1% learn

31.4% admin

25.1% research (6.8% this job, 13.2% last job, and 5.1% PhD research)

11.3% netwrk

0% teach

It will be interesting to watch how the balance between the categories shifts each month.

Well, that changes everything. Perhaps.

2011-11-25T02:43:00.001+11:00

I have heard it said that sometimes the most exciting moments in science are when you look at something and say “that’s odd!”. I had one of those moments today. I have been working on the paper from my post-doc research this week, and the main focus of my work has been the figures. I now have very good, clearly labelled BSE images of every sample analysed and am starting to reference them in the text of the paper. The process consists of saying things like “Garnet ranges in texture from thick rims overgrowing seeds to a spray of very small grains” and then adding parenthetical notes behind each type pointing to figures that show each sort. In the process I also listed those samples which have no garnet at all, with reference to their photos.

This is where the “that’s odd” moment came in. For one of the samples my table of results shows that it has garnet, and that I have five good analyses of it. However, the photo of that sample shows that there is no garnet at all, unless you count the seeds of a vastly different garnet composition that were included in each experiment to give the new garnet an easy place to start growing. Clearly something is wrong here, so I checked the data file and determined that the five garnet analyses we have for this sample were done by my predecessor in this project years before I arrived. In my own records I also have three analyses of garnet seeds from this sample. Comparing his data with my own shows that the garnet analyses he did are clearly *not* the seeds—for this sample the seeds are grossular garnet (the calcium end member) but the garnet he analysed are iron-rich with only a little Mg and Ca. Sorting all of the garnet data for all of the samples shows that his analyses for this particular sample fall nicely in the middle of the pack in terms of composition.

So what is going on? I can think of a couple of logical possibilities off the top of my head. One (kind of obvious one) is that I somehow analysed the wrong sample myself and the photo I have is not the sample I think it is. Another is that I did analyse the correct sample but there is something wrong with his data. A part of me hopes that it is the latter—not just because of vanity and the hopes that I did everything perfectly, but more because it would clear up a problem that has been bothering me with my results since I first obtained the data.

I ran my experiments at three different temperatures: 600, 625, and 650 C. For the two higher temps garnet was present for every pressure I tried. For 600 C, on the other hand, I found no garnet at all in any of the metapelite runs, but it was present in 3 of the 4 metagreywacke runs. Now, had those three been adjacent to one another I wouldn’t have complained. But they weren’t. Instead I had garnet present at 2.2 GPa, garnet absent at 2.5 GPa, and present again at 2.65 and 2.8 GPa. This makes it difficult to draw pretty diagrams. How much nicer they look when a phase is absent for one half and present for the other half of the diagram.

So now I sit and eagerly await a reply from my erstwhile boss to the email I just sent him. Depending on how he replies I will have work to do changing the write up to match the new situation—do I get to delete the analyses of garnet for this sample that he did, and write the paper with a story that makes sense to me, or will I need to beg him to find the real sample and put it into the microprobe and take new BSE images and do an analysis or three to confirm that the composition my predecessor saw all those years ago are correct, or…?

November writing challenge update

2011-11-18T20:16:00.002+11:00

Back at the end of October I put my hand up to participate in a science writing challenge for the month of November by finishing up two papers that really should have been written long since. On 1 November I started my new job, and didn’t write at all that first week as I focused on the 1001 tasks necessary to starting a new job, including moving into my office, rearranging the office furniture to suit my working needs, meeting my new colleagues, obtaining employee cards, library cards, etc.

Early in week two my office computer arrived, and another two potential writing days were lost installing programs and generally making the computer ready to use. However, on Thursday and Friday of that week I actually sat down and finished up the current draft of the paper based on my PhD research. The previous version I had done (while back in Australia in July) was good in terms of presenting the basic facts of what was done and what the results were, but I had been kind of sketchy in the discussion and conclusions section. (I think that is a common failing on my part that I should work on—I am totally comfortable reporting facts, and I am totally comfortable with editing a previously existing discussion/conclusion section, but actually confessing what *I* think is relevant or important about those facts? That is getting kind of personal.)

Be that as it may, since it was necessary to finish the paper I somehow found the necessary motivation/inspiration to just write it—I went back to my PhD thesis, looked at the points covered in that section there, and chose which ones to address here. Not only did I write it all down, in many cases the version in this paper is much clearer and more eloquent than what I had typed when finishing up the degree. Spending a couple of years thinking about other areas of geology actually helped give me some new insights on that project.

In this, my third week on my job I have continued to split my time between needful tasks for this project (doing background meeting, arranging a trip to the mining company with whom I will be working, obtaining a card to let me use the uni gym (free to employees during business hours), etc.) and finishing up previous papers. Since I had sent a copy of the PhD paper to my erstwhile advisor in Tasmania on Friday that meant I could focus on working on the paper from the experimental post doc position I finished last December.

This week I have managed to do some editing of the text and make major progress on a set of figures that should have been done long since: BSE images of every experiment, annotated to label the mineral phases present.

Why hadn’t I created such images previously? Because I documented each microprobe session in CorelDraw. My standard operating procedure was to look at the sample, determine a region to work on, take a picture, transfer it to my personal computer, open it in CorelDraw, and create a new layer for the day’s session in which I would make colour-coded circles superimposed over the picture at the locations for each analysis point. I would give each circle a name that matched the name recorded in the microprobe (such as RC1-NMg1 for the first garnet analysis on sample #RC1-NM). Repeat for each analysis, taking additional photos as needed.

This works very well for recording things, and one can easily go back and compare the results with the appearance of the phase analysed. However, the layers can get confusing for those samples with multiple microprobe sessions (due to the difficulties in getting good results for some phases).

The new, improved, pdf images I am creating for each sample make things much easier—they are all labelled with the pressure and temperature of the experiment, which bulk composition was used, and which phases are present. The phases are colour coded to indicate the quality of the data—if they are in bold print I had five or more good analyses of that phase for that sample which agree. If they are in normal print there were three to five good analyses, if they are in red there were two (or fewer) good analyses, and if the red text has a question mark next to it I know that the phase is present, but it was too small to get a clean analysis so I do not actually know the composition of the phase. Having this information right there with the photo of the sample is very helpful. It is also pretty easy to see why the red text is in red in most cases—those phases really are smaller or too amorphous to get good readings—one can see that in the photo, too.

There is still a week and a half left in November—I think I may be able to finish compiling these images today, so there is a chance that I will be able to complete all of the other tasks necessary for this project before the month ends. However, even if I do not complete this goal, I still thank Anne for having inspired me to set it—I am certain that I would have found plenty of tasks to keep me busy instead of writing these older papers if I had not stated publically that I would do it.

Intriguing distractions

2011-11-04T01:26:00.002+11:00

One of the things I have been reading in the process of learning the things I need to know for my new job is the book "Description of regional geological and geophysical maps of the Skellefte District and surrounding areas" A comment in the introduction caught my eye "Application of geophysical methods in metal exploration started more than three centuries ago in Sweden. Magnetic methods were in use as early as 1640.".

Sadly, the paragraph did not list a source for this information. However I see that one of the editors of the book is my boss, so I have emailed him to ask if he happens to know of the source. I did see a couple of books from the 1800's cited in the bibliography, so perhaps one of them could be the source. It looks like our library might have them, but they are in Swedish. While my language learning has gotten good enough to easily read children's books and books that I have read before in English, I fear that I am not up to trying to track down obscure references to magnetic methods which were in use in the 1640's. So instead I will make note of it here—perhaps next year I will be fluent enough to chase up that information, if my boss doesn't have a useful reply (he is traveling now—he has been at a conference all week).

Ok, back to real work, the clock is ticking…

Taking up the gauntlet

2011-11-01T08:00:00.001+11:00

Anne, over at Highly Allochthonous, has set a challenge for herself, and the rest of us—get those papers we have been meaning to write finished up and ready to submit during November. The timing is perfect. While I have had, in theory, 10 months with nothing to do but write up the results of my research, in reality I enjoyed my time of unemployment by doing non science adventures with my new love. But my life of leisure is at an end, starting with tomorrow, 1 November, I am employed once again.

I know from experience that starting a new job can make it difficult to finish up papers from the last project, but they tell me that it could be 10 days before I get a computer in my office and I won't have the meeting to get the data from the mining companies until some as-yet-to-be-determined date, which is a grand excuse to seriously sit down and catch up on those last few tasks to finish up the two papers that have been in progress for longer than they should have been. Stay tuned for updates on progress towards this goal…

texture short course, day one

2011-10-11T04:49:00.000+11:00

Back at the beginning of the summer I saw an ad for a workshop on texture analysis to be held in Tromsø in October open to students and researchers. It sounded interesting, so I sent them a note asking if it was open to researchers who are between contracts, and they said that it was, and (more importantly given the "between contracts" part, the only course fee would be to cover the copying expenses. When I got the job offer for the position I will start on 1 Nov. I asked if he thought I should attend the workshop, or if my time would be better spent staying home and reading literature directly relevant to the project. After looking over the flyer for the course he said that he thought I should go.

It turns out that the most efficient way to get to Tromsø from Luleå is to drive—they have no train this far north, so one would have to switch to a bus part way there, and flights go south to Stockholm and then west to Oslo or Trondheim before heading back north again. Therefore I checked with a friend of mine who is a graduate student with a flexible schedule, and he thought a road trip sounded like a good idea (besides, going away for a week might actually get him to do some writing). We had a nice drive up on Sunday—left Luleå just after 08:00, and arrived at our B&B (located 15 minute walk from the Uni) just after 18:00. (I, of course, forgot to take out the camera once during the drive, since I was so busy gazing out the window at the lovely mountains once we got close to the Norwegian border).

The course is divided into two sections—the first two days we are learning how to use the programs they use here to convert a series of rotated photos of thin sections into data showing the orientation of the crystallographic axes. The technique works only on uniaxial minerals, such as quartz or calcite (or ice), but since these often occur in units which have been deformed it is a useful tool.

It was very enjoyable to be back in a classroom again after a longish break, though a bit of a challenge to keep up with the exercise—the program we are using runs only on MacOS, and I haven't really needed to use Apple computers since my class in programing Basic on an AppleIIe back in highschool. Apple products have changed a bit since then, and while there are similarities in the handling between Apple and PC there are just enough differences that I found myself pushing the wrong button more than once and then frantically trying to undo that and get back to where I was meant to be before the teacher had gotten so far ahead that I couldn't catch up. Sometimes I managed it, sometimes I was the voice saying "wait, what folder was that?".

Fortunately, she was very patient when we got lost, and would back up and explain the steps we hadn't caught so that we could go on to the next step. I think we all managed to convert the raw data into the correct formats and align the stacks of images properly. Tomorrow we get to actually process that data into the sorts of final images that wind up in publications…

The next adventure has been revealed

2011-10-05T19:02:00.001+11:00

As of 1 November I shall be employed again. True to my pattern thus far it will be for something I have never done before. My Master's research was a structural geology project focusing on the deformation style and timing of a specific fault in the Brooks Range, Alaska. My PhD research focused on the metamorphic history of all of Tasmania, my first post-doc position introduced me to experimental petrology as a tool for understanding subduction zone processes. Now I am about to start a research position focusing on 3D (and 4D) geochemical modelling of VHMS ore deposit systems in northern Sweden.

This will be a project with a steep learning curve for me since the last two projects focused on metapelitic rocks and now I will need to learn the intimate details of volcanic rocks and what happens when they not only contain ore deposits but also have been subjected to greenschist facies metamorphism.

Needless to say, I left the meeting where I accepted the job offer with a bit of light reading in hand—one textbook: Introduction to Ore-Forming Processes and one PhD thesis: Volcanic Stratigraphy and Hydrothermal Alteration of the Petiknäs South Zn-Pb-Cu-Au-Ag Volcanic-hosted Massive Sulfide Deposit, Sweden. This thesis contains cross sections of one of the important deposits in this area—my project will be to take this sort of research to the next step—modelling the actual volumes involved in 3D.

I will look forward to reading these during the next couple of weeks before the job actually starts—in theory I will be in a much better place to hit the ground running by doing so. If any of you have suggestions for things in the literature that I really should read if I hope to do well with this research feel free to share them here. It is time to start reading 1000 words a day from the geologic literature again. I stopped at the end of last year when my job ended and haven't picked it back up during my extended vacation between jobs. I have enjoyed the holiday, but it is time to refocus on science and learning.

and the draft comes back

2011-09-27T17:43:00.000+10:00

Any readers who have been paying attention for a while know that I have yet to actually publish the results from my PhD research. My first attempt at a paper draft, written during the first month or two after starting my first post-doc position got a "this reads too much like a thesis, you are putting in too much information" reply from my advisor. Somewhat discouraged I set that project aside and didn't make much more progress on it during the 1.5 years of that post-doc position—only really managing to take it out once in a while, dust it off, work on it for an hour or three, and set it back aside.

However, when I was back in Australia this July (applying for my visa to settle in Scandinavia with my partner), I met with my advisor. Together we determined what I needed to do with the paper, and I managed to leave him what felt to me like a very good draft before boarding the plane to return to the northlands. Today, at long last, he has returned that draft to me with comments. Not surprisingly, his main point now is that the paper has become too short—while culling stuff from the too long version I got over-enthusiastic. Fortunately, this time he has concrete suggestions as to what should go back in, and why. Therefore I now have a goal: try to get a new, improved, draft back to him before my job interview next week (since, if I get the job I will want to focus my energies on learning the new position, rather than finishing up overdue projects). With luck I will not only accomplish that goal, but it will land on his desk at a time when he is actually able to reply promptly, rather than having a month or more slip by before he can even look at it. Perhaps one day in the not too distant future I can change the status of that paper from "in progress" to "submitted"…

how to get a PhD when you aren't a goal-oriented person

2011-09-13T23:49:00.001+10:00

This afternoon I found myself in a conversation where, once again, I described myself as not terribly goal-oriented. Nearly every time this comes up people express surprise—how can I not be goal oriented and yet have a PhD—isn't that achievement only possible if one is driven to achieve a fairly major goal? The answer is that, no, that is not the only way to get that degree. Certainly many who have one are goal oriented and used that goal as the driving force for all of the work that is required, but not me.

In my case I went to University because I loved learning and had so much fun in high school that I wanted it to continue. For me there was never a question of "what kind of job will this degree get you later?", but only the question of "what cool things do I wish to study now?". The beauty of my approach is that one gets to ask that question over and over again, each time one registers for a new term, and each time the answers will be slightly different. What got me to move on from undergraduate classes to graduate school was the discovery that someone would pay me to be a student. This sounded much better than paying to spend my time learning things, so I completed my Bachelor's degree and enrolled first as a Master's student, and later as a PhD student. Once I enrolled in graduate school I did work towards completing the degree, but not because I was driven by the goal of obtaining the degree, but because when someone else is paying for my education it comes with a certain obligation of actually doing well in my classes (with the Masters) and the research (both Master's and PhD). Besides, both programs came with a limited-time offer on their funding—the rules of the game were clear—your funding runs out after a certain number of years and you have a choice—get the degree by then, or go without. I may not be goal oriented, but I do have a fairly strongly developed sense of responsibility, and if my part of the bargain for the "free" education is to complete the degree, well, yes, I do have what it takes to do it.

but I thought such things were fiction

2011-08-30T17:23:00.002+10:00

Although I have been busy enough with other aspects of my life that I haven't been doing much science of my own (unless you count kitchen baking experiments) I am continuing to read the various emails I get from geology lists. The list for people who are part of the mineralogical society of America has often proved to be an interesting one. One of yesterday's posts was no exception. It mentions a revolutionary invention for decomposing rocks into individual mineral grains, a plasma discharge device, which was shown at the Goldschmidt conference in Davos a few years ago.

The poster reports that "The action is based on the fact that the electric conductivity is elevated on grain boundaries and a plasma discharge at 50 keV proved to break up a variety of rocks into single crystals. The rocks included a metamorphic shale (greenschist facies) with amphiboles, garnets, sulfides, etc; a marble broke into perfect calcite rhombohedra, sphalerite and galena crystals - an amorphous shungite delivered intriguing round graphitic aggregates plus much fine grained graphite."

Plasma discharge? Really? That sounds like something I heard about on Star Trek as a child, but would have assumed was naught more than "technobabble". It is kind of delightful to hear that such things really exist. I would love to see such a toy—what a great way to isolate garnets or monazite for further analysis. Though, sadly, one would lose all of the wonderful information available from in-situ analysis, perhaps the larger amount of statistical information to be obtained by getting all of the grains in the sample in their whole form might make up for that.

and the adventures continue

2011-08-04T14:38:00.001+10:00

My mandatory holiday in Australia, wherein I applied for my visa to move permanently to Scandinavia to live with my partner, turned out to be only three weeks long. This was a long time to be separated from him, but only just long enough to accomplish what I wanted to with the trip. In between visiting with friends and family I managed to get what feels like a good draft of my paper from my PhD research written and handed in to my adviser for his edits/comments, and had some very good discussions with him about the research/experiments I did in Italy that will be useful when I return to finishing up the paper from that project. But before I do that it is time to enjoy the rest of my love's summer holiday with him, and go camping at the Medieval Week in Gotland. Time enough to return to being a scientist after indulging personal interests.

and the adventures continue

2011-08-04T14:38:00.000+10:00

My mandatory holiday in Australia, wherein I applied for my visa to move permanently to Scandinavia to live with my partner, turned out to be only three weeks long. This was a long time to be separated from him, but only just long enough to accomplish what I wanted to with the trip. In between visiting with friends and family I managed to get what feels like a good draft of my paper from my PhD research written and handed in to my adviser for his edits/comments, and had some very good discussions with him about the research/experiments I did in Italy that will be useful when I return to finishing up the paper from that project. But before I do that it is time to enjoy the rest of my love's summer holiday with him, and go camping at the Medieval Week in Gotland. Time enough to return to being a scientist after indulging personal interests.

How quickly we fall back into good habits

2011-07-15T21:36:00.001+10:00

Working on my PhD project necessitated developing a number of good habits with regard to work patterns. Although it has been two full years (and a week or three) since I finished my thesis and got on a plane to start my first post doc position it turns out that some of my work habits from here are tied to the town, not just the house in which I lived then. Now that I am back in Tasmania I am finding it easy to pick up the pieces of that project and get back into "thesis mode", breaking the list of things that need to be done into tiny bits and working on them. Taking breaks to exercise, get food, and catch up with friends I have not seen in a couple of years, but still being way more productive than I have been in the past six months since that post-doc position ended, when I was on what is better described "vacation mode".

While it was a delightful vacation, I find that I am enjoying working on this project once again. Today I looked at thin sections of my samples in the microscope. The first thin sections I have seen in person since leaving (I had plenty of microprobe time analysing the experiments I did, but no actual rocks to play with). I would say that I had forgotten how pretty they are, but, really, I hadn't. I do have plenty of photos (and good ones!) of these samples, but there is something nice about being to rotate the stage and see the colours change.

why you should publish before you finish your degree: a cautionary tale

2011-07-11T21:53:00.002+10:00

When I completed writing my PhD thesis two years ago I boarded the plane the very next day to head off to my first post-doctoral position. Somehow, while I made a few attempts to write a paper based on that research during the 1.5 years of that post-doc contract, I didn't actually finish writing it—the first couple of drafts were still attempting to include too much information.

It will come as no surprise to anyone to hear that I continued to not work on that paper during the six months I was in Scandinavia on a visitor's visa living with my new-found love. Now that I have returned to Australia to submit my application for a permanent resident visa so that he and I may continue living together I have begun again, at long last, to working on that paper. One advantage to waiting until now is that instead of discussing the paper and the proper aims and scope thereof with my erstwhile adviser over email I can stop into his office and get real time interaction and feedback.

Today we had our first face-to-face meeting in two years, and he cautioned me that he expected that, given how long it has been since I have worked on this project, that it would probably take a good three days just to re-familiarize myself with what I was doing so that I could move forward on the project. How I wish that he weren't correct in that.

I recall having, on more than one occasion, cursed previous researchers who studied these rocks for the information that they left out of their theses or publications. Today I am cursing myself for what, now, appears to be a fairly random organizational system which has made it difficult to find the spreadsheets I need.

An additional complication I have encountered is my computer upgrade. I purchased a much-need new computer last October, and while I was able to replace most of the programs on it, it was not possible to replace my copy of ArcMap. This is the program in which I recorded the positions of each and every analysis point from every microprobe session I ever did during my PhD research. It is a wonderful program which permits one to accurately align photographs with x-y coordinates such that one can see at a glance where on each crystal each analysis point is located.

In the course of my research I exported the images for many of the samples to CorelDraw in order to create figures to be used in the thesis. I now wish to create a new figure for the paper I am working on, but the exported version contains the location of the analysis points for three out of four of the minerals used in the calculations. This means that I need to open the ArcMap files. I should be able to do this when next I am at the university, by using one of their computers, but it will require a bit of effort to explain to the program the new location of all of the files required.

So now the researcher who I find myself cursing for incomplete information is none other than my past self! There is no one to blame but me, each time I chose to do something other than writing this paper while the information was all still fresh in my mind I was also choosing to make the eventual writing of the paper just that little bit more difficult. I freely admit that, at the time I made those choices, it seemed like a reasonable price to pay, but now the time is nigh, and, indeed, it looks like it just may be a good three days to get back up to speed on this project so that I can finish it.

Wish me luck—as one of my colleagues pointed out to me today "research which is not published is wasted effort", and I do not wish all of that effort to have been wasted.

Google+ for geologists

2011-07-08T11:13:00.000+10:00

I am not certain if this is a good idea or not, but when a friend sent me a Google+ invite to my personal email address, I used that address to send an invite to the address attached to this blog. After all, this is the address that I keep logged in and have my GoogleReader geology feeds set up. Unlike the account associated with my personal email address, which had no suggestions of people I may know, this address came with a bunch of suggestions, several of whom I recognize as fellow geobloggers. Therefore I created a circle called "geologists" and added them to it. I have no idea if it tells you that you are now in my circle, but if it does you now know why…

It let me set up "sparks" for "metamorphic petrology" and "orogenesis", but they don't look like they have much information available at this time.

orogenesis

2011-06-27T05:43:00.002+10:00

I have been far too busy enjoying the fact that I moved to Scandinavia for love to post very often, but I feel compelled to play in this month's Accretionary Wedge. My favourite geology word would have to be orogenesis. I love mountains better than any other land form, and the process of their formation is endlessly fascinating. The microscopic changes which happen in the metamorphic rocks at depth during mountain building are rich with information about the processes that built the peaks.

Metaphorical rocks

2011-04-15T17:24:00.000+10:00

I have been taking a language class since moving to Scandinavia so that I can learn to understand the local language. Last week we had a homework assignment to write about our new city, and there was an essay in the textbook that we could use as an example/inspiration for our own writing.

Being a geologist with little interest in cities my essay didn't look much like the one in the book, which focused on various tourist destinations in a major Scandinavian city. Instead I spoke about the fact that January was a good time to arrive here because then it is cold enough it doesn't rain, mentioning that I do not care for rain in the winter, but I love snow, and find the ice-crystal covered trees much prettier than bare trees. From there I went on to discuss the interesting people I have met, and ending with a paragraph explaining that I am looking forward to summer because then I will be able to see the rocks; I have been told that the local rocks are ______, and that is the prettiest rock type.

The word I had in that blank was meant to be "metamorphic". However, when I asked my favourite on-line dictionary for the local word for "metamorphic" it didn't know the word, so I instead called upon Google Translate, which helpfully provided me the word "metaforiska", so I used it. However, when the teacher returned my essay she wrote on the page "metaphorical? Is that really what you meant?" Oops! Checking Wikipedia the local language it turns out that the word I should have used was metamorfa.

However, when I think of it further, it occurs to me that, perhaps, I did choose the correct word after all. Metamorphic rocks, can, indeed, serve as a metaphor for life. In this world we are born as soft, yielding creatures (babies = ocean floor sediments). Over time we are subject to heat and pressure ( = rules from parents & society) which gradually transform us into first older children (phyllite) and then teenagers (low grade schist) and finally mature adults (high grade schist, mylonite, or even migmatite) with the record of our experiences both moulding who we are as people and leaving a permanent record in our souls (zoning in porphyroblasts, inclusion trails, flow banding, etc…) The more difficult the life, the more character we develop, and the stronger we need to be (which is why the prettiest rocks are the ones which are most deformed).

links to other blogs

2011-04-01T17:23:00.001+11:00

I just read a wonderful series of posts by Life in a Plane Light describing how metamorphic reactions turn boring old mud into beautiful garnet schist. If anyone missed it, part one talks about the factors that make up metamorphism, the second talks about the first changes that happen to the mud when heat is applied, and the third adds deformation into the equation and gets us to the garnet. If you haven't read them yet they are so worth a look.

slickensides vs slickenlines

2011-04-01T03:51:00.000+11:00

In my current job I am learning any number of interesting things as I look things up in the course of editing so as to be certain that terms are being used correctly. Today's noteworthy subject to look up is the difference between the terms "slickensides" and "slickenlines". I only recall the former from my undergraduate structure courses, and neither term has come up in my own research since then. There was a time when looking up such geologic terms meant reaching for a geologic dictionary. These days it can sometimes be more effective to reach for the internet. I just found an interesting article which nicely clarifies the difference between the two words, and why there are two such closely related words in the first place.

Slickensides refers to the planar, polished, surface of a fault plane (the polishing occurring when the rocks rub past one another. Slickenlines, on the other hand, refers to the liner scratches which occur on such a surface, as a projection on one side of the fault scratches a grove onto the other. Most of the slickensides I have seen in the field contained slickenlines. No wonder my teachers and classmates simply used the term "slicks" when discussing them informally in the field.

What an effective way to learn!

2011-03-17T07:02:00.000+11:00

I recently replied to an advertisement looking for people to do editing of geoscience journal articles. They first sent me a one page test document to edit to see if they were happy with my ability as an editor, and when I passed that exam they sent me an actual article to do. What a fun assignment! In order to properly edit a sentence one must understand what the writer intended to convey, and in order to do that one must understand the context—what procedures did the author carry out, what were the results, and what do they think it all means? I have written before about "active" reading, and the advantages that can give one in understanding the content of a journal article. It turns out that for me I am able to get even more information out of an article when I edit it, one sentence at a time. I have sent the first article back; I really hope they like my work with it and decide to send me more. I have so enjoyed learning the topic of this paper that I wish to do it again with other papers.

what goes into making a thin section before we can do optical mineralogy?

2011-03-09T19:26:00.002+11:00

There has been a lively discussion on the MSA-Talk e-mail list the past few days on the subject of optical mineralogy. Life in a Plane Light has a very nice summary of the discussion and an update of other posts that came in after the first summary.

I have been following the conversation with interest because optical mineralogy is very important to metamorphic petrologists. For those of you who are not familiar with the process a brief description is in order. Step one is to obtain an interesting rock from the field—break off a hand-sample from the outcrop (a chunk of rock small enough to carry in your hand), record on your map the location from whence it was obtained, and write down any important observations you have made about the outcrop (how large is it, does it contain more than one rock type? What sort of contacts separate the rock types? What structures are present? If your sample has any structures which are measurable (foliation, lineation, strike & dip of the rock itself) measure them *before* obtaining your sample, and make marks on the rock with a waterproof marker showing what you measured and what the measurements were—then carefully break that portion of rock away from the outcrop without destroying the marks.

Why is step one so important? Because knowing the field relationships of your sample really helps your understanding of what you will see in the thin section once you have it.

Step two is the creation of the thin section. To do this we use a rock saw to cut the hand sample open. If there are structures of interest in the sample (foliations, lineations, etc.) it is important to make the cut at an angle of interest. There are times when one wishes to see the minerals parallel the structure, times when one wishes to the minerals perpendicular to the structure. If the structure is complex one will likely wish to make more than one thin section of the rock at more than one angle.

We use the saw to cut a small rectangular block of rock out of the hand sample, with one of the long sides of the rectangle oriented in the direction of interest. If your sample is an "oriented" sample (it has marks on it showing what was measured in the field) take care to transfer those marks onto the small block so that you will know which way is "up" or "east" or "north", or whatever orientation you have marked. Once the hand sample is a small block we polish one side of it (the one which is oriented in the direction of interest with respect to the structure) and when it is very smooth we "glue" that side to a glass microscope slide (using a rock appropriate epoxy). At this point we record the sample name on the glass, and also transfer any marks showing the orientation of the sample to the glass itself (this can be done low-tech by scratching on the glass with a nail, or high-tech by using a laser, or with a few other options in between of intermediate technology levels) After the epoxy has set we use a rock saw to cut away most of the rest of the block of rock (which we save for later comparison with the thin section—it can be helpful to also polish the face of this block that was closest to the glass before removing it).

The next step is to polish the thin layer of rock which is attached to the glass slide. This is done carefully because at the end of the process we wish the layer of rock remaining attached to the slide to be only 30 microns thick (remember that there are 1000 microns in every millimetre). The reason we wish it to be that thin is because at this thickness many of the rock forming minerals are translucent—light will pass through them.

This is where the "optical mineralogy" part really begins. By using a petrographic microscope we can see and identify the minerals in the sample and see their relationship to one another. How do we do this? By carefully comparing the various features we can see with an understanding of the features usually displayed by minerals. A course in optical mineralogy teaches us how to distinguish one mineral from another based on their colour or lack thereof, how high is their "relief" (does it appear to stand up above the plane of the glass slide, appear to be lower than that plane, or more or less lie in the plane?), what is its crystal habit of each of the minerals? All of these clues, taken together, permit us to recognize the minerals.

Once we know which minerals are present we can then make observations of how they relate to one another. Are they all aligned with their long axis parallel to the same direction (foliated)? Is that alignment a planar feature, or is it folded? Is there more than one foliation? Are some minerals present only totally surrounded by (included within) certain other minerals? When minerals are present both as inclusions and within the matrix is there any difference between them? (are the inclusions smaller or larger than the same mineral in the matrix? Are they oriented the same direction in both locations? Is there a colour change from one to the other?

These are just a few of the things we look for in a thin section to help unravel the story of the rock. When I was an undergraduate student we not only had a dedicated course in optical mineralogy, but it was a requirement of the course to make one thin section ourselves, starting from collecting the sample in the field and ending with a report about all of the minerals present in the sample and their relationship to one another and what we learned about the rock thereby. In those days we had to make a drawing of the thin section which showed these relationships.

Now days we have fancy, high-tech optical microscopes with motorized sample stages that are attached to powerful cameras and computers. As a result we can program the machines to take a series of photographs at very close scale of thin section, then "stitch" them together to make a single high-resolution image of a large portion of the thin section, which we can then annotate in a drawing program, labelling the minerals, tracing the structures, etc. For those of us who are not practiced artists this is a much better approach for illustrating what we see in the thin sections. However, in the old days a talented petrologist with a steady drawing hand was able to do drawings of thin sections which are works of art and which show an amazing amount of detail of what is in the sample. For a good example of this check out the book Metamorphic Textures by Alan Spry, published in 1969 (ISBN: 0080133169 / 0-08-013316-9), which appears to be available for purchase in pdf form these days, though I haven't tried to do so.

serendipity

2011-02-28T22:48:00.000+11:00

I have been in Scandinavia for two months now, and this weekend I decided that it was time to see if I could learn anything of the local geology on line, since the rocks are still too snow covered to be revealing many of their secrets to my own observations. So I called upon Google, as you do in such situations, and requested information on "Luleå geology". Much to my surprise the first hit was an announcement of a faculty position at the local university, the one within walking distance of my new home. They are looking for someone to teach ore deposit geology and conduct research on that topic. The translation of their ad says that this means that one uses "geochronology, isotope geochemistry, tectonics, structural geology, mineralogy, etc. to explain and describe the processes by which metals are transported, concentrated and precipitated".

This description made me smile; while I have not focused upon ore deposits in my own research their list of tools used is pretty much a one to one match to the list of research interests/tools on my CV. Reading the fine print of the ad I see that previous experience in research on the topic of "malmkaraktärisering" (ore characterisation) is "meritorious", rather than "required". This, too made me smile; I may not have done much with ore deposits myself, but I am a graduate of CODES: the Centre for Excellence in Ore Deposit Research at the University of Tasmania—all of the short courses and most of the seminars I attended were on ore deposit research of one sort or another, often sharing very cutting edge research or technological applications. Therefore, while I may not have the "meritorious" advantage of having done my own research on the subject, I have absorbed a fair bit of information on the topic over the years, and have a good idea of which colleagues to turn to if I have questions on any particular topic in the field.

While writing the application (read: taking information from my CV and inserting it into their template) I thought about what to put into the "future research" section of the document. This caused me to recall a particularly interesting seminar talk while I was still at CODES, so I e-mailed the speaker and let him know that I was preparing the application and would be interested in doing collaborative research using that technology should I be the successful applicant. Much to my delight I received an encouraging reply in plenty of time to include his name in the application. He also reminded me that the honorary doctorate degree he'd received a couple of years back happens to have come from this university. I am taking this as a positive sign, and happily turned in my application this morning (today being the application deadline—I saw the ad only just on time!).

I have no idea how I will do with this application—it matters as much what the other applicant's packets contain as it does what I have included in my own, but I am confident that should I be the lucky winner in this case I will be able to do the job, and do it well. How lovely it would be to be able to work in the town I have chosen for personal reasons. However, if it doesn't work out I am certain that I will enjoy whatever path I do take…

too busy too be bored; too happy in the north to want to move south

2011-02-10T18:16:00.000+11:00

I have some friends who are unemployed and looking for work who complain on certain social media sites that they are bored. My contract ended with the end of December, so, technically, I am also unemployed, but I am far, far too busy to be bored (as people might be able to guess if they compared frequency of my posts before and after the contract ending).

What am I doing to keep busy? I'm getting close to done processing the data I generated during the last couple of weeks before I left; I should be able to actually begin the writing process within a week. I'm settling into a new home with a new partner in a new country, and trying to learn a new language. Our evenings are full with folk dance classes, choir practice, gaming with friends, visiting a local climbing wall, martial arts practice, and, of course Medieval Re-enactment. My days are full with finishing up my last research project, trying to keep up with personal correspondence, studying my new language and attending class for that, dealing with the bureaucracy at the Uni (why do they need copies of my highschool, BS, and Master's transcripts before they approve my enrolment in a beginning language class when they have my PhD transcripts? (Doesn't the one sort of imply the existence of the others?) I am also starting the paperwork for appropriate visas to actually be able to stay here.

I'm also continuing the job search, but now that there are two of us to consider I'm being a bit fussier about the jobs for which I will apply—I have never been interested in hot climates, but had been applying for interesting sounding jobs located in such places anyway, with the thought that I could endure hot weather for a short time and then when I have more experience move on to someplace with good weather. Now that I'm happily living somewhere far enough north to have real winter I am much less inclined to consider locations without winter, and my partner, like me, loves the snow and cold weather.

I listen to friends who live in more southern locations complain about winter—that it is cold, dark, wet, and depressing. I am convinced that the reason they think this is because they are too far south. Up here in the north (though still south of the Arctic Circle) winter may be cold, but it isn't wet, and it isn't dark or depressing. Instead the snow reflects light beautifully, making even overcast days brighter than their counterpart down south. And day, like today, when there are no clouds, are sometimes overwhelmingly bright. Yes, the sun does set early, but we are living in a town, which means that there are street-lights, which means that the snow is reflecting that light all night long, so visibility is good and it is neither dark, nor depressing.

I have been saying for a decade that I really miss real winter. Now that I have it again I don't wish to move somewhere without it. Now for the fun part: either finding an academic job which will let me do interesting research and live in the north (but with mountains, too, please!), or obtain funding which will let me choose my own location to live and do research…

Siccar Point revisited

2011-01-29T00:27:00.000+11:00

Some time back I shared my photos of Hutton's famous unconformity at Siccar Point, Scotland. Yesterday Chris over at Highly Allochthonous shared a video he made which gives one a much better view of the unconformity than still photos. Thanks Chris!

dating one's research

2011-01-23T17:44:00.004+11:00

I don't normally read on-line comics, since I tend to have too many things to read in the way of e-mail, friends posts to their facebook, livejournal and blogs. However, today one of my friends sent me this link from the PhD Comics, and I thought it worth sharing with others. Having done a thesis kind of recently I really understand what the author is saying. Yes, yes indeed, one really does get *that* close to one's research project...

on musicians, Phd's, and following one's dreams

2011-01-19T20:43:00.000+11:00

I should be working, but instead I have been enjoying catching up on reading various social networking sites and some blogs I follow. Today's highlight is a guest post on FSP's blog written by an MSP she knows. It is a very good comparison between the life of a graduate student with the life of a musician. It was written in response to those folk who say that doing a PhD is a waste of time. In that respect I don't know how effective it will be; perhaps those same folk will also think that being a musician is a waste of time. Be that as it may, I enjoyed the comparison. To my mind any life which follows one's personal interests and passions and encourages one to strive to better oneself in one's chosen field(s) is a good thing!

Ok, now it is time to close my web browser, open those files I was working on before heading north at New Years and see if I can find exactly the right words to describe the research with which I was occupied for the past 1.5 years so that I may share it with the world via a journal article…

fablous fold photos on line

2011-01-15T00:37:00.001+11:00

For those of you who missed today's Friday fold photos you might want to go click on this link and spend time admiring the really pretty folds from the new Structural Geology textbook by Haaken Fossen at the University of Bergen, Norway. If the book is half as nice as the on-line photos from it it would be a wonderful addition to any library.

Photos from my Schnaels Valley trip last September and again in October

2011-01-13T00:31:00.026+11:00

Back in early September I took a week off of a busy schedule attending academic geology conferences and short courses to attend the Second Annual European Textile Forum—a conference designed for both academics and living history enthusiasts who are interested in historic textiles. As a long-time participant in historical recreation events who loves hand-sewing and is fascinated with ways in which fabric and other textiles are created I really enjoyed the chance to meet and mingle with others who also love the subject. As with the textile forum of the year before, I reveled in living in a historic setting—this time we were at the Archeoparc in the Neolithic, surrounded with tools found with Otzi, the Ice Man.

However, for me the wonderful people met and the sharing of information on any number of textile arts was only part of the joy in the week; the rest of the joy was the setting itself. The Senales valley is a place of beauty, and it was fun to get out and look at bit at the rocks. I so enjoyed my week there that I returned again in October when my mother was visiting and did some more exploring. Here are some of the highlights of the geology I saw in my explorations of this valley in the Italian Alps.

One of the cute little farms in the lower part of the valley:

And the near-by outcrop:

The view above the Archeoparc historical buildings:

The church just downhill from the park (and some nice outcrop to the left):

Much of the rock of the part of the valley where we were staying is a lovely fine-grained schist:

In places the locals use the rock to form part of their storage sheds:

In other parts of the hiking trail up the valley it is just a pretty part of the landscape:

Not far uphill from the Archeoparc there is a damn which holds back a cute mountain lake, though I'm told that there are people who are still annoyed about losing their family farms when it was put in.

The schist gets coarser as one works one's way further uphill towards the ski resort:

In places there are some lovely quartz boudins:

I saw some pretty clear contacts:

In October there was already some decent snow on the peaks; I wonder how it looks now?

to cast the sandwich

2011-01-06T09:05:00.000+11:00

I spent much of December packing up my belongings and sending them off to storage; with the New Year I flew to Sweden to visit friends and do some travel. This evening I learned a delightful phrase "kasta macka", which means to "cast the sandwich", or to "skip rocks". However, in this case, the "sandwich" referred to is the flat, sedimentary rocks which have weathered into stones which are perfect for skipping across the surface of a body of water when thrown at the correct angle.

My travels in 2010

2010-12-20T06:07:00.003+11:00

I see that Silver Fox is playing a game wherein we recount the travelling we've done in the past year. That page links to others who have played as well. Since I love travel, and have done a fair bit recently, I thought I'd join in, but I'll start with December of last year, just because many of you have only just finished with this year's AGU:

December 2009: I flew to California for AGU, and while there visited with many friends who live in the area as well, then flew to Seattle for my mother's birthday, and then home to Alaska for the first time in many years.

2010:

January: I returned to Seattle for a few more days with family and friends there, then back to California for a few more days with friends there before returning home from a month-long holiday based around AGU.

February: Attended a short-course on Microstructures in Verbania, Italy

March: attended a Scientific Writing Workshop in Zurich, Switzerland

April: Petrology conference in Tolouse, France

May: EGU in Vienna, Austria

June: Meeting of my research team in Norway (Trondheim, road trip to Florø, and boat trip to Bergen, then train to Oslo for flight home). Also a non-geology road trip to Germany for a Medieval event.

July: two trips for Medieval Dance events, one in Germany, the other in Scotland.

August: Trip to Ireland to visit friends, to Budapest, Hungary for IMA.

September: Kinetics course in Vienna (went from IMA to Vienna, rather than going home in between), and the European Textile Forum in the Italian Alps, followed by the Italian geological society conference in

October: Back to the Italian Alps with my mother, and then we flew off to Finland to meet family there for the first time, then to Scotland for a job interview.

November: to Stockholm, Sweden for another Medieval Dance event.

December: to Cambridge, UK for another Medieval Dance event.

By my count that is 10 trips for geology meetings, conferences, short courses, or interviews, four for medieval dance events, one for medieval textiles, and six for strictly personal reasons. It is a good thing I like travel!

The most difficult stage of the writing process: what to include?

2010-12-19T00:12:00.001+11:00

here are many things I love about being a scientist—doing research, whether it be in the field or the laboratory is just plain fun. Processing the data after gathering it can also be much fun as it is transformed into useful information and patterns start to emerge. However, my least favourite part of any research project is deciding what parts to share with the world in the form of a published paper. Why? Because I suffer from two conflicting tendencies—on the one hand I suffer from Too Much Information Syndrome, where I want to share with the reader *everything* I tried in the course of research and painstaking details about the manner in which some of the avenues of investigation failed to work and exactly why others were more effective. But on the other hand, I also suffer from the tendency to want to cut things too short—to neglect to mention the background information that I understand which is crucial for really grasping what it is that I have done and why it is significant. Somewhere between these two extremes lies the happy middle ground that leads to a published paper. Once I've managed to get past that somewhat daunting decision of what information to include, and what to leave out, the rest of the paper writing becomes a joy once again. It can be fun to craft the perfect sentence which conveys, in the most eloquent manner, the complex concepts that underpin the investigation. I enjoy the editing and revision portion of the process nearly as much as the data-gathering. Therefore, wish me luck as I go through all of the data generated (and still being generated) in my (nearly) 1.5 years as a post-doc (final experiment to be analyzed for the first time on Monday and Tuesday!) and try to determine what parts to share with the world, so that I may move on to the more fun parts of transforming the first draft of the prose into eloquence.

motivation, 1000 a day, and winter holidays

2010-12-15T12:40:00.000+11:00

A year and a half ago I was finishing up my PhD thesis, working really, really long hours and totally focused on the one goal: finish up before boarding that plane on my way to my first post-doc position. Many of my friends commented at how motivated I was, and I replied that plane tickets are a huge motivator.

Jump ahead to the present and I once again have plane tickets waiting for me at the end of the month, but this time they are taking me to visit friends in Scandinavia and enjoy some real winter weather while I keep applying for jobs. Since my friends will have jobs to go to during the days the prospect of not being quite finished with my current research isn't as worrisome as the prospect of not completing that thesis before boarding the plane to head to a job—I know that it will be possible to keep working, even once funding ends. As a result I have not been putting fort the same sort of concentrated effort I did a year and a half ago, but am instead permitting myself some distractions.

One of the biggest distractions, of course, is the need to continue to apply for all of those positions which sound interesting and related to any of the research I've done to date. Each of these applications takes time, and each has a deadline by which if I have not yet applied they will not consider me for the position. One of the other distractions has been my social life. I flew to Scandinavia on the last weekend of November, and to the UK on the first weekend of December. Both trips were to attend events focused on Medieval Dancing. I very much enjoyed both trips and got to renew some old friendships and make some new friends.

Prior to the first of those trips I had been wondering what to do about my 1000 a day—I had chosen to fly carry-on only, and wouldn't be bringing my computer—this means that I'd need to actually print out a pdf or bring a text book so that I'd have something with me to read from the geologic literature. Sadly, a couple of days before my trip I forgot to read my 1000, thus ending a streak of 321 days in a row. My record, by far, and I am pleased to have achieved it. But oh, wouldn't it have been nice to manage an entire year in a row of reading 1000 or more words from the geological literature?

I know how it happened that I forgot, too. Much the same way as the last time I broke a record-breaking streak. Step one: get into the habit of reading your 1000 right before bed for many weeks running. Step two, switch to reading during lunch for a week or three. Step three: encounter a particularly busy day, with no time to read your 1000 during lunch. Think about it a couple of times during the day that it still needs doing, but only while actively in the middle of another, important task. Finish up everything else for the day, do yoga, brush teeth, crawl into bed, and pick up some fiction. Read till you sleep, and don’t remember that the 1000 hadn't been done till you wake.

Having forgotten I then made a decision to take a hiatus from reading my 1000. I will start back up after the first of the year, but I am taking December off (I wound up taking off much of last December, too, as I traveled and visited friends and family after attending AGU). It is strangely freeing to have one fewer "must do" on my list each day. However, I strongly suspect that I will be very happy to start that task back up again with the New Year.

Birthday blogging

2010-12-10T18:28:00.001+11:00

I am currently enjoying the final month of my contract—this means trying to accomplish all of the "last things" that have to happen before this research becomes a published paper in between packing my things to go into storage, purchasing tickets for some post-contract travel, and applying for jobs so that I have somewhere to go when the travel phase ends. Needless to say, I haven't been making much time to post blogs, but since I've always taken a random approach to the timing of them anyway, perhaps no one will notice.

Today I get to celebrate my birthday week by playing with expensive toys—more time on the electron microprobe to generate yet more data. I am looking forward to it—there is much fun to be had looking at minerals in that much detail. At this point in my project I've got the routines down to convert the data into useable format, so should be able to have it incorporated with the preceding sessions before the weekend is over. Working on the weekend? You betcha—best way to assure that I am actually done (enough) with my research when the contract ends.

An alternate hypothesis for columnar jointing

2010-12-01T04:11:00.005+11:00

Anyone who has ever taken a geology class has probably heard the explanation to explain columnar jointing in basaltic rocks—cracks that occur as the molten rock cools quickly due to its sudden emplacement in a much cooler setting than where it first melted. However, a friend of mine browsing the web today found a picture which shows another possibility for the long vertical lines that occur in cliffs of columnar jointed rock:

(The above image was found here.)

Extrapolation of the likely composition of a mineral from mixed analyses

2010-11-24T06:52:00.008+11:00

I have mentioned before the difficulties of using a microprobe to analyze very small phases. The electron beam with which we do the analysis can, with care, be focused to about 1 micron diameter (remember that there are 1,000 microns in every millimeter). However, should the mineral phase of interest be smaller than one micron, in any dimension, the analysis will yield the composition of not just that mineral, but of whatever happens to be next to it as well.

The below photo shows one of my experiments for which this was a problem. As with all back-scatter electron images the amount of brightness or darkness of any given part of the image is based on the composition of the sample in that location. Brighter areas contain more heavy elements, darker areas more light elements. The brightest grains in this image are the large pale grey crystals, which often have dark centers; these are garnets. The dark centers are the pyrope (Mg-garnet) seeds that were included in the experimental powder to give the new garnet, which is much higher in Fe (iron), a place to start growing from. The narrow stick-shaped crystals which occur in a group on the left hand side of the image are chloritoid. Unfortunately, as you can see by the scale bar on the bottom of the image, they are too narrow to obtain a good analysis. Through careful searching of the sample we found a few places where the chloritoid grains were slightly larger than the others—these were the ones we analyzed, in hopes that we would be lucky. Alas, 15 times we tried, and 15 times we failed to obtain an analysis which was only chloritoid, but instead they were "mixed" results of both chloritoid plus another phase.

How do I know for certain that they are mixed? Look at the below graphs and you can see for yourself. The upper graph shows the composition of all of those mixed analyses with respect to how much aluminum and how much silica they contain (blue-green hollow triangles). It also shows the region (grey circle) within which all of the matrix mica in this sample plots, and the location of where kyanite (Al₂SiO₅), also present in this sample, plots. As you can see, there is a clear trend going from the solid green triangle towards the mica, and another trend going from the solid green triangle towards the location of kyanite. The lower graph shows the trends for iron vs aluminum. By plotting this data for a variety of different combinations of elements I have come up with my best guess as to the composition of chloritoid is in this sample (solid bluish-green triangles). Is it as accurate as if I'd been able to get a good measurement? No. Does it give me information I can use when doing other parts of my data analysis? Yes, yes it does. Playing with graphs is one of the fun parts of my job—the information they convey communicates so very clearly.

Final experiment of the project

2010-11-19T22:34:00.001+11:00

What is probably my final experiment (for this project) is running. We started it yesterday morning. My current contract runs through December. At 2 to 3 weeks per experiment, this one is probably it. This fact left me torn as to what conditions to choose for the run.

I've got a couple of previous experiments which turned out to be very difficult to analyze due to improper sealing of the capsules. Therefore I'd love to re-run them, with properly sealed capsules, in hopes of better grain sizes, so that I can get good analyses of the phases present.

We've got some data from experiments run by a predecessor of mine which use a slightly different bulk composition. In theory the difference between the two bulk compositions shouldn't really matter—most of the difference is in the amount of SiO2, which is still in excess in the bulk composition I use (as we can tell from the presence of quartz). However, when I calculated what phases should be present for each bulk composition using Perple_X, it said that at the P/T of those old runs the new bulk should have different phases. Therefore I'd like to re-run one of those to see if there is, in fact, any difference in the results with the slightly different composition.

And, finally, both my boss and I wanted to do another run in a P/T space that is expected to have both garnet and talc, since this project is about defining the stability field for talc. That makes three different experiments I want to run, and sufficient time available to do one of them. Decisions, decisions!

We eventually decided to go with a totally new run—while the data from the "bad" runs isn't complete, we do know that there isn't talc present at those conditions, which is the single most important question. Therefore there is more value in obtaining new data than clarifying old data in this case.

All in all, this project has convinced me that 1.5 years is simply not enough time for such a project. However, I am pretty certain that if it had been a 3 year contract that was now approaching its end I'd still be sitting here thinking about the other experiments I would have liked to have run, had there been time/budget to do so. Ah, the life of a research scientist—so many questions to be asked, so many things to do to try to answer them, but no matter which ones we choose, it never, really, feels like we've got time enough to obtain all of the data we would like to have…

What is the deal with Academic Conferences, anyway?

2010-11-17T21:34:00.000+11:00

In a comment to yesterday's post I was asked "What's the deal with academic conferences? Do you have to be within the correct academic circles to attend or is there some degree of public allowance?" I started to type up a reply, and then realized I had enough to say on the topic to warrant making a separate post on the topic.

Most academic conferences are open to anyone willing to pay the admission fee, which is often higher for people who aren't a member of the sponsoring organization. However, it is often worth purchasing a membership to the organization if you wish to attend their conference, as the amount you save on registration fees is larger than you'd spend on the membership, particularly if you are a student, since student memberships are usually quite affordable compared to the "professional" membership rate). If all you want to do is attend as a audience member, hear the talks, have coffee with the folk there, check out the info booths and see what is being sold in the booths offering stuff for sale all you need to is pay the registration fee and you are good to go.

However, If you want to share your research with others you need to look over the various sessions being offered, find one wherein your research fits the theme, prepare an abstract describing your research, submit it (and the abstract submission fee) before the deadline *and* register to attend the conference (and pay the registration fees, too). Often when submitting an abstract they ask if you prefer to do your presentation as a poster or a talk. However, even if you choose talk you might wind up doing a poster anyway; if they have too many talks offered for a session they will choose some of them to be posters instead. It is also possible that a session won't accept someone's abstract at all, but I have yet to see an example of this.

Another reason to attend conferences (at least in Geology, but possibly in other sciences, too) are the pre-, post- or mid- conference field trips. Most conferences offer 1 to 5 day trips to look at the highlights of local geology, with the trip led by people who have long worked in the area. These are excellent opportunities for networking, and, more importantly, they tend to showcase some of the best outcrops available in a region, so there are many opportunities to increase your photo collection of interesting geologic features, or to add to your sample collection (note: not all areas permit sampling—please listen to the rules at the start of the trip and respect them).

Short courses are another highlight of many conferences. There are often courses on speciality topics that are held at the conference because it saves the students the travel costs—much cheaper to attend both on one trip than to do to separate trips. Note that field trips and short courses are usually priced separately from the conference registration. Luckily, students who enjoy funding that includes conference attendance can usually attend courses and/or field trips without having to pay for them out of pocket (or, at least get reimbursed afterwards).

The final reason to attend conferences is the social aspect. This varies from one to the next, but I have seen offerings ranging from Ice Breaker Cocktail nights, to Conference Dinners, to Ceilidh Dances, to Choir rehearsals/performances to sporting events.

I may have missed the GSA meeting, but…

2010-11-17T11:52:00.000+11:00

I just saw a post by Life in a Plane Light which really makes me wish that I had been able to attend the Fall GSA meeting this year. As a metamorphic petrologist I love garnet. Sure, it is a pretty mineral, but the usefulness of this mineral in learning about the history of metamorphic rocks is what makes it truly fascinating. Fortunately, while I may not have been able to attend the session on Garnet and Its Use in Unraveling Metamorphic and Tectonic Processes , the abstracts are available on line to read at will. I've just done well more than my 1000 words of reading from the geologic literature reading these abstracts, and wondering why I hadn't thought of looking at the program sooner. Just because one can't attend a meeting doesn't mean one can't benefit from the information that is shared there.

The difference between moving where one must and where one can

2010-11-15T14:45:00.001+11:00

When I was a child my father was in the Air Force. As a result I lived in 4 countries on three continents before I was 7 years old. When I was little moving was something that happened every 1 to 3 years—we went when dad's orders to move came in, and we went where they told us to go; often with not much advance notice. Then my parents split, and the next couple of times I moved it was at my mother's whim when and to where. After I turned 18 I resumed moving every few years, and became accustomed to being the one in control of where I went, when, and for what reason.

It wasn't until my PhD was drawing to a close two years ago that where/when I moved once again became something over which I have little control. Two years ago, knowing that my funding had run out and that I really like the part where I can afford to eat, I begun to apply for every post-doc and teaching position I could find that sounded even sort of interesting, regardless of where it was located. One of those applications resulted in a job offer in Europe, and, as soon as I finished my thesis, off I went.

Now I am once again in the position of applying for every interesting sounding job I hear about. I have chosen not to apply to a couple because of location, but I have also chosen to apply for a couple for which my CV isn't a perfect match because the location is so appealing. In a way I feel almost like I'm a kid again, waiting for dad to get his orders that tell us where we are going, and when. I love moving, but 1.5 years in a large city, even one with lots of trees lining many of the streets (and, most importantly the street upon which I live and upon which my office is located) has convinced me that it would be nice if I could move someplace I would love. Somewhere with mountains, lots of nature/wilderness easily accessible.

Some of the job applications I send in are much like lottery tickets—they might not pick my numbers as the winner, but if I don't enter I haven't got a chance. Others I apply for because I know that my CV is a very good match for what they are seeking, and I feel obligated to apply, despite the location. Which will it be? When will I find out? Life is, as always, an adventure!

Does anyone remember this story?

2010-11-11T22:33:00.001+11:00

Sometime back in the 1980's I subscribed for a year or so to the Magazine of Fantasy and Science Fiction. During that period of time I read a short-story (probably in this magazine, but possibly elsewhere) which involved a person who was able to see a different landscape than the one which is currently present—able to see different plants and animals than are currently living. I think that the people in the story worked out which geologic period (s?)he was seeing by comparing the descriptions of what was seen with a geologic map. Alas, I read that story before taking my first geology class. Now that I am a geologist, I would love to go back and read it again. However, I have no idea what it was called, who wrote it, or even if the geology part was a minor interesting side part of the story, or the overriding plot device. Do any of you remember reading this story?

this is delightful!

2010-11-07T06:11:00.002+11:00

I just saw a link over at Earth Learning Idea to a delightful web page, made by Cary and Michael Huang, which shows the scale of the universe. They've got a blue box you can slide back and forth, to see things at all scales. A very delightful toy.

Time to work, time to play

2010-11-05T20:45:00.000+11:00

The November Scientiae Carnival asks: "What is the best part of your job/life as a scientist, and what is the worst part?"

For me the answer to both has got to be the freedom to set my own schedule. I love the fact that I can work whenever I want/feel inspired/have energy, so if I feel like working all night long (like much of this week), I can do so. However, the down side to such a schedule is that it can be difficult to take time off without feeling guilty for not working. People who have jobs which require them to be there at specific hours are free to play during their non-work hours. Those of us who have jobs which aren't tied to a clock, on the other hand, may be free to select which hours are work and which are play, but it is easy to get caught in the trap of thinking during play that one should be working.

Folded tracks

2010-11-03T00:24:00.000+11:00

One of the things that holds the most appeal for me in the science of geology is the physical expression of deformation. Folds are pretty! I love to see folding in rocks, at all scales. Today I saw a beautiful photo of folding in response to deformation that isn't in a rock. Go over to Dave's Landslide Blog for some amazing photos of the bending of some rail-way track in New Zealand in response to their large earthquake earlier this year.

Spooky deskcrops

2010-10-29T21:56:00.002+11:00

This month's Accretionary Wedge asks us to share photos of our favourite deskcrop, with bonus points if it is spooky. As one who moves, often, I have managed not to accumulate a personal collection of rocks, but rather catalogue them appropriately and store them in the collections of which every university I was with when I collected them. However, I have many photos on my computers of my samples. My personal favourite "spooky" rock photo is this back-scatter electron image of a monazite grain. Every time I see it I think I'm looking at the skull of some sort of humanoid creature.

This was one of the many grains in Tasmanian metamorphic rocks analyzed for U-Th-Pb dating for my PhD thesis. Analysis of a point near the optic lobe of the skull of this grain gave an age of 508 +/- 5 Ma for this grain, which is in good agreement with the main Cambrian metamorphism within Tasmania.

Lots of choices; life is good

2010-10-29T21:19:00.000+11:00

This morning Female Science Professor discussed an interview she did with a first year student on the topic of How We Choose A Career. This subject has been on my mind a lot lately, as I am sending out applications for my next job. There are ever so many interesting sounding directions I could go from here. I'm applying to positions that are teaching-based and others that are research-based. I've applied for post-doc positions, lab-tech positions, and even museum curator positions. Each of these vastly different jobs all have one thing in common: they sound like fun. I still have no idea while I will be doing when this contract ends in December. Perhaps I will be rushing straight off to start a new job right away in January. Perhaps I will have a few months off to relax and travel before I start the next job. The only things I know about my next job with reasonable certainty: It will probably be on Earth, and I will probably enjoy it.

The rocks under St. Andrew's

2010-10-29T08:58:00.005+11:00

I enjoyed another visit to Scotland last week. While there I went up to St. Andrew's, home of the third-oldest English-speaking University in the world. In addition to a noteworthy University, the town's other tourist attractions include the ruins of a castle and a cathedral.

These first two photos show what is left of the castle up at the ground level.

Here is the view from the beach, looking up at the castle.

This is the cliff just to the left of the castle, showing the sedimentary rock upon which the castle is built.

This is a tunnel under the castle. During a siege the attackers dug a mine, hoping to get under the walls and blow them up. But the folks in the castle heard them digging, dug a counter mine, and managed to fend off the attackers in the tunnel.

Here is a view through the walls down onto the beach, showing more of the sedimentary rocks below.

While the rocks in this part of Scotland aren't as pretty as the metamorphic rocks in the interior of the country, still it was fun to see the interaction of the human history and the geology.

transition to day-shift

2010-10-17T21:37:00.000+11:00

The past three weeks and a bit have been even busier than usual. My mother arrived from the US on the 25th of September for a visit and stayed through to this weekend. While she was here I took the weekends off to go sightseeing with her one weekend, and to return to the ancestral home in Finland to meet some delightful family I didn’t know I had on the other. In between I’ve been working and preparing a talk for an upcoming job interview.
The Interview will take place starting at 08:20 in the morning, and as a result of that start-time I decided to adjust my schedule to being on day-shift starting from the day I got the letter letting me know the day/time. For those of you who have been working jobs which are tied to “business hours” for years being on day shift is unlikely to sound remarkable. However, I have been in academia for many years now, and am accustomed to setting my own schedule. While I have had occasional things that are tied to a specific day/time (such as conferences), most of what I have had to accomplish has been to deadlines that are not precisely defined (e.g. the degree will be awarded when you’ve completed your research and written the thesis). As a result my sleeping schedule has tended to wander around the clock based on the whim of the moment. Some days I accomplish my most productive work after midnight. Other days it is in the morning, and still others I’ve got the most energy in the afternoons or early evenings. This flexibility has served me well, and permitted me to achieve my goals thus far.
However, if I land the job for which I will be interviewing it will be one of those wherein I will need to report to work during business hours. Therefore for the past couple of weeks I have had two alarms set. One to go off every day at 21:55, to tell me to stop what I’m doing on my computer, go home, do my yoga, and go to bed soon, the other which goes off at 06:30 every morning telling me to get up and start my day. This seems to be working very well. Some days I am aware that it is closing in on 10 pm, and I’m wrapping up what I’ve been working on before the alarm tells me that I need to. Some days I’m so absorbed in my work it goes off and I’m surprised when it does. On those days it is harder to stop, but I have been making myself do so anyway. (Other days I’m not working at all, but only hanging out on line chatting with friends—it is hard to stop that because the clock says so, too, but my friends have been supportive of my wish to be on day shift, and encourage me to actually say good night promptly, even when they are in a another time zone and it is still hours before their bed time.)
One advantage of this schedule is that I am finding it easier to make time in the mornings to go for a run or put on my rollerblades before breakfast. Somehow, even though there are the same number of hours available in a day no matter which ones I choose to be awake (assuming that the total number of hours I sleep is constant), I feel like I can delay the start of my working day more when I get up at 06:30 than when I get up at 09:00 or 12:00 or 16:00). All in all, I pronounce this experiment a success, and feel confidant that should I be offered a job which requires that I be on day shift that I will thrive, even though it isn’t what I have been used to.

Deformation in the Desert field trip 2007

2010-09-25T01:28:00.036+10:00

Today I read a post by Anne over at Highly Allochthonous on some major flooding she witnessed on her trip to Alice Springs in 2000. This reminded me of my one trip to Alice Springs (it wasn’t flooding when I was there). Since my trip pre-dates my starting this blog, I thought I’d share with you the write-up I did for friends and family.

The below was written on 14 July 2007.

I just returned from the "Deformation in the Desert" Conference, held in Alice Springs, Northern Territory, Australia, sponsored by the Geological Society of Australia Specialist Group in Tectonics and Structural Geology.

The highlight of the conference was the five-day pre-conference field trip (photos below) which looked at the Palaeozoic tectonothermal evolution of the Irindina Province of the eastern Arunta Region. The trip started out in Alice Springs, headed south through the Heavitree Quartzite Gap (the ridge is a wall just south of town, the rocks steeply dipping, with a couple of gaps where the "rivers" cut through--though how you can call a waterless stream course a river, I don't know). From there we took the sealed (read: "paved" if you happen to speak American) road east and thence north into the Strangways and Hearts Range metamorphic complex. As soon as we turned north we were on dirt roads, and stayed on them for most of the rest of the trip.

Each day saw us rise before the sun so as to have breakfast before hitting the road. We stopped at many interesting outcrops, and at each stop the trip leader would show us the map, remind us of the geology at the last stop, tell us about the current stop, and then let us know what the next stop held in store for us. By the end of the trip I had a good understanding of the geology of the region! There were just about 40 people on the trip, including the catering group. They took good care of us, feeding us well (even us fussy eaters with special dietary requirements), and provided "swags" for each of us--a sleeping bag, mattress, pillow and water-proof canvas cover for the lot. We slept each night on the sands of (dry) creek beds, under the stars. There was no rain, nor any clouds (nor would any have been expected), making the camp sites safe enough, though in rainy seasons (once every several years) flash floods would be a problem (see above mentioned post by Anne).

The conference itself was held in Alice Springs and, unlike the conference I attended in Melbourne the year before, had only one track of sessions, so there was never a problem deciding which talk to attend--we simply attended all of them! Most of the talks were interesting, quite a number were very, very well presented, and only one was bad.

Stop 1: Ross River Gorge

Stop 2: Bitter Springs Formation, view to the east

Stop 3 Arumba Sandstone

Stop 3B Ross River syncline

Stop 5 Strangways Metamorphic Complex, with lovely garnets (800C, 6Kbars)

Stop 6: fold in mylonite zone

Stop 7: Argument Gorge, mylonite zone

Stop 7: stretching lineations on mylonite surface (this was the first time I'd seen a good exposure of a mylonite, and suddenly everything I'd been reading about them made so much more sense!

Stop 9: garnet rich boudin (some exceed 1.5 cm)--I liked this stop!

Stop 9, garnet showing sense of shear

Stop 9: mafic layer + garnet sand

Stop 10: near Lizzy creek, view north to the Hearts Range

Stop 11: an old mica mine in a pegmatite dike. Note huge sheets of mica that still litter the ground

Stop 12 Bruna Granitic Gneiss--view to the east

Stop 13: Mt. Ruby garnet zone in amphibolite from the Hearts Range Metaigneous complex

Stop 14: Indiana Granite Hill. We climbed this one.

Us, at the top of Indiana Granite Hill (stop 14)

Stop 16: Huckitta Creek, Intense strain zone

Stop 16: folding
Stop 16: more of the intense strain

Stop 17: Large fold

Stop 17: large deformed pegmatite dike to the right of the above fold. Note boudins in the layers of the fold limb

Stop 19: fold in gneiss

Stop 19: view to the east

Stop 20: Bruna granitic gneiss:

Stop 20 garnet-rich metapelite:

Stop 20: a mylonite zone in gneiss. Note that the mylonite contains garnet, the gneiss does not.

Stop 21: a mica and garnet rich layer in gneiss:
Stop 21: folding in gneiss:

There was also a mid-conference filed trip--a one day trip to the west of Alice Springs, driving on sealed roads the entire time (in large tourist-style air conditioned busses). The person who sat next to me happened to have been from Tasmania, and graduated years ago from UTAS before moving to the mainland to do geology there. Needless to say we had some very pleasant discussions about the uni we both attended.

The rocks on the mid-confluence trip weren't as pretty (they hadn't been sufficiently deformed to show the pretty folding or nice minerals that we saw on the five day trip), but they were still nice, and we actually saw a few waterholes (one 30 feet deep) which stay wet year-round, despite the fact that the rest of the river course is dry.

Mid conference trip stop 1: looking west at the Arumba Sandstone

Mid-conference trip, stop 2 Elery water hole (and folding of the rocks)

Mid-conference trip Stop 3: anticline in Heavitree quartzite

Mid-conference trip Stop 3 Heavitree quartzite repeated above thrust fault
Mid Conference trip stop 3: Ormiston Gorge (with some nice folding showing)
Mid Conference trip stop 4: Mt. Saunders
Mid conference trip, stop 5: The waterhole at Glen Hellen Gorge

Note: all above photo captions were taken straight from the file names of the photo, I didn't have to look for my field notes from the trip today--I had the sense to give the photos meaningful names, including stop numbers and sometimes even P/T data promptly after taking them.

word of the day

2010-09-19T23:56:00.002+10:00

While reading a journal article* today I encountered a word I’d not noticed before: Aulacogen. The first mention in the article was "Continental extension that fails to lead to ocean opening and subsequently undergoes compression can occur at failed arms of ocean basins (aulacogens) and at intracontinental settings isolated from plate margins".

A quick check shows that there are 220 articles in scopus with that term used. (For comparison—“continental extension” yields 4,780 articles in scopus.) This is a somewhat specialized term, so I don’t feel bad that I missed noticing it (if, indeed, it has even been mentioned in the articles and textbooks I’ve read hitherto). Thus far my research has focused on the results of compression, be it deformation or metamorphism, rather than extension, so there would be no reason for me to think about what happens when extension starts and then stops before an ocean basin forms.

*Cawood, P. A., Kröner, A., Collins, W. J., Kusky, T. M., Mooney, W. D. and Windley, B. F. (2009). Accretionary orogens through Earth history. Geological Society Special Publication: 1-36.

two days of playing tourist amongst more than a month of travel

2010-09-18T03:59:00.007+10:00

When I first scheduled my late summer conference travel schedule it sounded like a good idea to attend first the IMA conference in Budapest, go from there to Vienna for a short-course on the Kinetics of Geological Materials, from there to the European Textile forum, and from there to the Italian SIMP conference. Indeed, I very much enjoyed each of them, in very different ways. However, after 3.5 weeks of non-stop travel and major time commitments happening each day (and, for the last couple of weeks very, very limited internet access), I find that this week has been one of recovery. I’ve accomplished the urgent tasks on my to-do list, but mostly I’m catching up on personal correspondence and basic housekeeping tasks. Now it is time to start blogging once again.

I will start with sharing photos from my weekend as a tourist. Since I had two whole days off between the Budapest conference and the start of the short course in Vienna I decided that it would make more sense to play tourist than to fly home and then head right back out again. Having many fond memories of a salt-mine tour I took with my father when I was a child of five years of age, I decided that I would take the train up to Salzburg and check out the mine again, now that I’m a geologist and will have a better understanding of what I am seeing. However, when I asked my mother she didn’t remember which of mines we went to all those years ago. Since there is more than one to choose from, I made the decision between them the easy way and went with the one recommended by my host—I choose to do CouchSurfing that weekend, so that I’d meet local people rather than staying on my own in a hotel room.

Since the weather in Budapest had been extremely hot and sunny, I was delighted with the cool grey clouds and gentle rain in the Salzburg area. Here is the view from the mine entrance in Hallein:

It was so very wonderful to be surrounded by mountains again—I have missed them so!

The rock in the mine has clearly undergone some deformation looking at the layers on the wall:

Being a tourist mine they have some old-style ore-carts full of rocks ready to haul away:

And a lovely display case of pretty samples from the mine:

Occasionally we could look up into a shaft reaching up to other levels:

They have a large lake in the mine that was used for mining—they put in fresh water, it dissolved salt from the rock, and they extracted and evaporated the brine. This silly statue has a slow, steady, drip of salt brine from the pump, and we were encouraged to taste it if we liked. Yup. Salty.

Alas, my photos from the rat trip across the lake didn’t come out. They do that part accompanied with eerie mood music and a light show. Made for an interesting effect, but felt like a scene from a fantasy movie, and not a real salt mine. This wall is from the far side of the lake:

Without a doubt the highlight of the trip was the slide between levels. This first photo is from the top of the shorter, warm-up slide:

And this photo is from the bottom of the longer slide:

It was so much fun that I climbed the stairs and went down the slide a second time. I can remember a slide from when I was a child, but I sure don’t remember it being this long or this fast. On the other hand, I do remember it as being a long way to fall sidewards if you weren’t wedged in between two grown-ups. This slide doesn’t have a place to fall to the side.

After leaving the mine I decided to walk the 3 km back down the hill to the town, rather than taking a bus, and I’m glad I did—I found a trail so that I didn’t even have to walk along the road.

And finally, the view back up the hill from the town:

I think that my early childhood visit to this mine, and the box of salt rocks that my dad bought me then, was a factor in my growing up to become a geologist. I loved my tour as a child, and found it just as delightful now. There is something comforting about having an entire mountain over my head. In hopes of encouraging the tradition I bought a box of salt rocks to send back to my nieces. This purchase was done with my sister’s encouragement, of course—she was too little to do the mine tour when we were there all those years ago, but she used to enjoy playing with (and licking) my salt-rocks.

A short course in Vienna

2010-09-05T22:42:00.001+10:00

As I type (Saturday morning 4 Sept 2010) this I am sitting on a train, traveling from Vienna to Zurich, where I will change trains for my trip home from my latest adventures. The plan, when I scheduled the travel was to enjoy the mountain views out the window, but the clouds are low, so while I can tell that there are hills out there, I can’t tell if they rise up into mountains. However, as we passed Salzburg I did get glimpses of the peaks as the clouds parted, so the time spent on the train will have been worth it for that view, if no others come along. With luck I will get a chance to post this once I’m home, since I don’t expect to have any internet access at all next week.

After leaving Budapest and the IMA conference I traveled first to Salzburg, where I spent the weekend playing tourist and visiting the salt mine at Hallein (photos from that trip to follow in another post), and then doubled back to Vienna, where I attended a short-course on the Kinetics of Geologic Materials.

The course turned out to be as useful as I’d hoped. I signed up for it in large part because, having had such a long break between taking my last math course and enrolling in my PhD program, I’d found that when reading papers I had a tendency to skip over formulas and jump to the next descriptive part of the text. In an effort to overcome this habit I have checked out text books on the thermodynamics behind the chemical reactions which form minerals, and, to some extent, they helped. However, I still felt like I was missing something in my understanding of the math/formulas that one needs to describe what is happening during mineral-forming reactions, and so this course.

There were more than 25 of us who signed up for the course, traveling there from Italy, Germany, Hungary, the Czech Republic, and more. We range in experience from advance undergraduate geology students to post-doctoral researchers. At the end of our course we shared information on our current research in a poster session ( good percentage of us had attended the IMA conference in Budapest), and our specialties range from experimental studies to traditional petrology—from the crystallization of minerals from a melt, to zoning in metamorphic minerals and a number of points in between. One student is even studying the ability of rocks in Hungary to store man-made CO2.

The lectures started with an introduction to thermodynamics—the study of the relationship to the energy of a system to the equilibrium thereof. The common physical example used to illustrate this point is to stand a rectangular block on its narrow end. So long as it is on a flat surface and nothing happens to it, it will happily stand there all day. However, being taller than it is wide, should anything bump into it the block will fall over and land on its broad side. We describe the block standing on its narrow end as “metastable”, because if energy is added (it gets pushed), it will transform to its more stable state of lying on its broad side. Chemical reactions are much the same. Minerals are each stable in a specific range of conditions (pressure, temperature, and composition of the rock itself), but some chemical reactions take more of a “push” to make them happen than others. In these cases the minerals will often exist in conditions during which they are not expected to exist, in which case, like the block standing on its narrow side, they are metastable.

From this simple example the course built up the mathematical framework of how to describe the energy used to “push” the reactions into happening, and how to use published values for that energy to determine for any conditions what minerals will be expected to be stable in an equilibrium situation. We touched on many related topics related to kinetics, including diffusion (how the elements within the minerals move from one location to another so that the chemical reactions will happen), nucleation (the earliest stages of the growth of a new crystal), and the boundaries between grains and/or phases. For most topics presented we also had exercises to work on during the lab hours—using MATLAB to perform calculations on these processes for model (simplified) systems.

All in all the week was a very valuable experience, but train has reached an area where the mountains are visible, so it is time to shut down the computer and enjoy the view.

Rock Painting at IMA

2010-08-28T07:18:00.003+10:00

At the IMA2010 Conference this year they had a variety of things scheduled in addition to Science. There were sporting events, music performances, and rock painting!

I chose to do a free-hand interlace knot:

The IMA Medalist is a snappy dresser

2010-08-27T03:36:00.000+10:00

My interest in clothing and fashion is normally restricted to 12th Century and earlier. I just don’t find the trends that fashion have gone through since then to be pretty. However, I couldn’t help but notice the beautiful black linen which formed the suit worn by Frank Hawthorne, winner of the IMA Medal for Outstanding Contributions in Mineralogy Research. Most modern men’s suits are polyester if they are cheap (and how they can tolerate to wear such a non-breathable fibre is beyond me), or wool if they are nice (much better!), but his is the first I’ve seen in linen (one of my favorite fibers), and despite being in a cut which doesn’t interest me, I couldn’t help but admire the colour (black shirt, black jacket, black trousers, all of a lovely, dark, shiny, new looking shade), and even thought the colour of the dark purple tie looked nice in contrast with the rest of the outfit. (However, I still don’t like the shape and location of ties. What is wrong with nice, contrasting colour collar and hems, like were used in part of the Middle Ages?)

But enough about clothing. What about his talk? That was fascinating. He managed to put an awful lot of very complex information into a fairly short amount of time, and while most of it was totally new information to me, he did it in such a way as I felt like I understood what he was saying the whole time.

His topic was from theoretical mineralogy, focusing on the bond-topological basis of structure stability and mineral reactions. He explained how the bonds between atoms in a mineral can be used to predict the stability of a compound. For simple atoms it is necessary that that the atoms on either side of a bond have roughly matching levels of acidity or baseness, making predictions easy—if the cation and anion involved have just about as much level of acid as base, then the molecule will be stable. He also demonstrated how this principal can be extrapolated up to very complex mineral structures, but while it made sense looking at it as he spoke, I’ll not try to explain it now without the diagrams in front of me.

IMA continuted

2010-08-25T19:55:00.003+10:00

First of all, I offer thanks to Tuff Cookie over at Magma Cum Laude for resurrecting her In the Humorous Vein series. It had been too long since one of her inspirational posters.

The busy schedule that is a week spent at a conference continues. I succeeded in getting my poster printed on time to put it on the poster board today (Thanks to Robert, the person in charge of helping IMA conference attendees with, well, everything, near as I can tell.)

One of the highlights of Tuesday’s lectures for me was the Element’s lecture by Nigel Kelly on Zircon. Anyone who saw the Zircon issue of the Elements magazine will recall what a useful (and pretty) mineral zircon is. Even though (or because of?) the fact that much of the information in the talk was review for me, having read that issue cover-to-cover I very much enjoyed the talk.

Here is the list of talks to which I’ve actually made it on Monday and Tuesday. There were others which sounded interesting, but, alas, the interesting talks in different areas of specialization often conflict with one another. It was also necessary to miss a few I’d have liked to attend while dealing with the logistics of actually getting my poster printed.

From the session MH111 History of mineralogy: The role of the Carpathian region in the 18th century:

Mottana, A.

The tradition of Theophrastus’ “On Stones” during the early stages of modern mineral science

Rózsa, P.

Sir James Hall’s visit in Schemnitz

Viczián, I.

Letters of German naturalists to Domokos: Teleki, the first president of the Jena Mineralogical Society

From the session H112 The scientific value of mineral beauty:

Garcia-Ruiz, J.M., Canals, A., Villasuso, R., Van Driessche, A.E.S. & Otálora, F.

On the formation of giant crystals of gypsum: the science behind beauty

Gilg, H.A., Krüger, Y., Taubald, H., Morteani, G. & Frenz, M.

Genesis of amethyst geodes at Ametista do Sul, Rio Grande do Sul, Brazil

Giuliani, G.

Emerald gastropod fossils from the Mantecanã mine (Gachalà district, Colombia): a record of the recipe for Colombian emerald formation

Feneyrol, J., Giuliani, G., Ohnenstetter, D., Galoisy, L. & Pardieu, V.

Is the V/Cr ratio a fingerprint of the geographical origin of 'tsavorite' in the Mozambique Belt?

From the session: MH110G – Mineral museums and Historical mineralogy

Müller, A., Rumsey, M. & Ihlen, P.

Historical minerals from the Evje-Iveland pegmatites at the Natural History Museum in London

Langhof, J.

Early 19th century scientific networking – a study in Jacob Berzelius’ mineral collection

From the session: GM72 – Accessory minerals: Tracers of magmatic and metamorphic evolution

Harlov, D.E., Williams, M., Jercinovic, M., Budzyn, B. & Hetherington, C.

Partial alteration of monazite and xenotime during mineral-fluid interaction: implications for geochronology

Finger, F., Dunkley, D. & Knop, E.

Multiple phases of monazite growth in the South Bohemian HP-HT granulites: a chance to constrain the entire timing of metamorphic evolution from subduction to exhumation by Th-U-Pb geochronometry?

Krenn, E. & Finger, F.

Unusually yttrium rich monazite with 6-14 wt.% Y2O3 in a granulite from the Bohemian Massif: implications for monazite-xenotime miscibility gap thermometry

Uher, P., Dianiška, I., Bačík, P., Ondrejka, M., Pršek, J. & Zubaj, R.

Gadolinite and crichtonite group minerals: breakdown products of primary monazite and xenotime in granitic and metamorphic rocks

Today is my poster session—we are meant to be at our posters from 14:00 to 16:00. However, today, at 14:00 is also the second rehersal of the IMA 210 Choir. Therefore I’ve written a note stating that it isn’t too late to join the choir, and inviting one and all to join the author of this poster at the 2nd rehearsal, and promising to return to the poster promptly after rehearsal.

before and after

2010-08-23T22:55:00.004+10:00

On Sunday afternoon I did a bit of sightseeing in Budapest, with a local guide—a couchsurfer who had stayed with me when he visited my city of residence back in November. Today I posted some of my photos to Facebook, and included the snippet of information that he’d shared with me—apparently all of the bridges connecting the cities of Buda and Pest were destroyed during WWII, but one of them was re-built in the same style as before the war. This is my photo of that bridge:

And this is a link he shared with me of how it looked in 1946.

Seeing his link had me nearly in tears. War is something of which I can never approve, and photos like that really bring home how truly dangerous they are. But the compare and contrast from the destruction then, to the beauty that is now is a tribute to human nature and our ability to sweep up and start over. May we never lose that ability, may we never cause others to need practice that skill, and may we never need practice that skill for reasons of our own causing.

first day of IMA2010

2010-08-23T19:54:00.002+10:00

Today is the first full day of lectures at the International Mineral Association’s 2010 Congress in Budapest. I spent the morning attending lectures on the topic of History. The first talk of the day was _The tradition of Theoprastus’ “On Stones” during the early stages of modern mineral science_ by A. Mottana.

He spoke on the ancient text written by Theoprastus usually called “De Lapidibus”, or “On Stones”, which was written around 313-305 BC. Its arrival to Italy in 1427, brought from Constantinople to Florence by Trancaso Filefo, was one of the important parts of the resurgence/rediscovery of ancient learning in the Renaissance, being the first entire book written on stones and minerals. The source of the document that arrived in Italy in 1427 is thought to have been the Vaticanus graecus 1302, a codex written in Byzantium c. 1300-30.

The lecture opened with a definition of the period of the Renassiance, which started in Italy in 1392 when Manuel Chrysoliora was appointed to teach Greek Language & Literature at the University in Florence, and ended in 1611 when Johannes Keppler published Strena Seu de Nive Sexangula, which was the first mathematical text on crystal structure, and thus an important start to the age of science. From there he touched on the various Renaissance scholars who used this source in their own work, and who did translations, and when. The talk was fascinating, but due to the format (only 20 minutes available) it was necessary for him to hurry over the latter portion of the talk, and my note-taking didn’t keep up. (Any errors in the above are due to my rusty note-taking skills, and not to the speaker).

My flight to Budapest

2010-08-22T04:15:00.002+10:00

I flew to Budapest this morning, to attend the upcoming IMA2010 Conference (Aug. 21-27, Budapest). When I finally turned on the computer this evening there was an e-mail from the conference organizers announcing that this event “includes in its programme 13 plenary lectures: seven IMA2010 Plenary talks and six Elements5 talks (the latter celebrating the 5th anniversary of our excellent journal). The topics cover all representative areas, and they are tailored for a broad audience, while the authors are well-recognized experts in their fields, but also attractive speakers.” They also announce that those of you who weren’t able to come out for the meeting can still follow along at home by listing to their live web casting (end public service announcement).

Because I had a morning flight it was necessary to leave my home at 04:00 to begin my journey to the airport. Therefore I decided to just stay up all night, thinking “I can sleep on the plane”. However, what I failed to consider was that the flight path went along the south side of the Alps, for a rather large portion of the range’s extent. Consequently, while I did nap in the bus on the way to the airport, and at the airport itself, I spent the flight with my eyes focused out the window, enjoying the lovely view. Some of the peaks in the second row in still have snow on them, which sight is balm to eyes that have had to endure summer’s heat. I have no idea where I’ll be going when my current contract ends, but I sure hope it is somewhere that I can see (and walk in!) mountains on a daily basis.

Article review: “Metamorphism: from Patterns to Processes”

2010-08-17T18:17:00.005+10:00

As a member of the Mineralogical Society of America I receive a paper copy of the journal, Elements, each month. Some of there previous issues have focused upon a specific element or a specific mineral. The June 2010 issue (Vol 6, #3), on the other hand, focuses on Fluids in Metamorphism. Needless to say, as a metamorphic petrologist this caught my attention. I’ve just finished reading the article titled Metamorphism: From Patterns to Processes by Bjørn Jamtveit, who is located at the Center for Physics of Geological Processes at the University of Oslo and decided that it is worth mentioning here.

This article is a very good one for underscoring one of the reasons I am fond of metamorphic rocks: they are pretty! He includes a variety of figures to illustrate the types of changes that happen to rocks as a result of metamorphism (change), with a focus on how those changes are facilitated by the presence of fluids. As a teaser for the article, I have copied his figure 1 below. The first photo is of a dark, fine grained basalt (formed by the cooling of lava after it erupted from a volcano), which contains the minerals augite, plagioclase, and olivine, though the individual grains of each are too small to see at this scale. The second photo is of a lovely eclogite, which contains red garnets, green omphacite, and white clinozoisite, all of which are much coarser-grained than minerals in the basalt. Metamorphic processes are responsible for the transformation of basalts into eclogites.

The differences in the crystal structures of augite-plagioclase-olivine vs. garnet-omphacite-clinozoisite mean that the eclogite is a denser rock (~3.5 g/cm³) than is the basalt (2.9 g/cm³), which, the figure caption tells us, means that the transition from one to the other is important for large-scale geodynamic processes, including basin subsidence and subduction.

In addition to illustrating the beauty of metamorphic rocks, the article also touches upon the factors that cause the change, and how long these processes take. I highly recommend it to anyone curious about metamorphism.

My host’s great-grand father

2010-08-14T23:16:00.003+10:00

When I was in Norway earlier this summer, rather than staying in hotels I chose to couch surf, for much of the trip. There is something quite nice about staying with local hosts; one gets to meet people one wouldn’t have otherwise met, and one gets to learn something about the local area and the people who live there. Or, in some cases, the people who have lived there long ago.

My host in Bergen, when she discovered that I’m a geologist told me about her great-grandfather, who was a geologist, so I looked him up. Tom Barth (1899-1971) published over 200 papers in his life in the fields of mineralogy, petrology, and geochemistry. When he was young he studied with Goldschmidt and Eskola, names that should be well known to anyone who has ever read a basic metamorphic geology text. He was one of the people involved in the early stages of developing an understanding of the way crystal structure works, and was the first to demonstrate that chemically different atoms can occupy crystallographically identical sites.

What fun serendipity that my host while I was traveling happens to be descended from a scientist whose life-work comprised an important part of the framework that was a necessary prelude to my own research.

What is the difference between contact and regional metamorphism?

2010-08-12T23:00:00.003+10:00

In the comments on a recent post I was asked about the difference between contact and regional metamorphism, and thought that the answer deserved to be a post of its very own.

First of all I should remind you that “metamorphism” is about change—specifically the changes that take place in a rock due to changes in temperature and pressure. Each mineral has a range of temperatures and pressures at which it is “stable”. When in that range it exists happily because the pattern of the atoms within its crystal structure is appropriate for the conditions. If there is a large enough change in the temperature and/or pressure the minerals become unstable. If that change takes place slowly enough and the new conditions are held for long enough the unstable minerals will undergo chemical reactions to grow new minerals out of the component elements of the old minerals.

However, if the change is too fast the “unstable” minerals will continue to just sit in their rock, doing nothing. This latter feature is a good thing—without it we would never see high-pressure rocks at the surface. Diamonds are a high-pressure form of carbon, and graphite is a low pressure from of carbon. Their ingredients (only the element C) are the same, but their crystal structure is very different. The carbon atoms in the high-pressure version are packed much closer together than the low pressure version. If the diamonds didn’t come to the surface so quickly they would have been replaced with graphite (or the carbon would have been used to create some other mineral).

So today’s post is about those rocks that experienced new conditions in temperature and/or pressure long enough that chemical reactions happened and new minerals grew in response to the new conditions. There are a couple of ways this can happen: Contact Metamorphism and Regional Metamorphism.

Contact Metamorphism is what happens when something really hot (like a body of magma (molten rock) comes in contact with colder rock. The rocks get cooked, just like when one pours pancake batter onto a hot frying pan. Anyone who has ever made pancakes knows that over the course of the cooking process there is a range of textures to the batter before one flips it to cook the second side. The part against the pan got the hottest. As a result the liquid in that layer is completely cooked away and the solid turns a golden brown (or even darkens to black if left unattended too long), the next layer out from there also becomes firm, but with a different texture than the crust, and the far side of the pancake, which is exposed to the air, is still cool enough in temperature that it hasn’t solidified at all yet.

This is similar to what happens to (relatively) cold rocks that have been intruded by molten rock. The layer of rock closest to the intrusion heats up the most, and any fluids escaping from the rock as a result of the heat participates in the chemical reactions of the “cooking” process, so a suite of minerals grow in the layer closest to the heat source that are indicative of high temperature. The next layer out doesn’t get quite as hot, so a slightly different suite of minerals grows there, and even further away from the intrusion the temperature is lower still, so lower temperature minerals grow.

These sorts of patterns were very helpful in formulating theories of metamorphism in the early days of the development of our science, as geologists could easily find places where the pattern can be traced from completely unaltered “country rock” through a series of gradually more and more metamorphosed rocks right up to the contact with the intrusion. In places where there is good outcrop one can see that the layers form concentrically around the intrusion.

Regional metamorphism, on the other hand tends to involve much larger packages of rocks. It is often associated with mountain building (orogenesis), and happens when an entire region gets buried deep enough so that both pressure and temperature increase. This increase causes new minerals to grow. Regional metamorphism is, often, something that happens over a much larger body of rock than contact metamorphism (which goes a long way to explain why “regional” was chosen as the name). It also, often, takes place at higher pressure than contact metamorphism, since it takes a certain amount of depth to achieve the sorts of temperatures at which the metamorphic reactions take place, and that depth comes with corresponding pressure increase as well as temperature increase. Regional metamorphism takes place at a variety of temperatures and pressures, which have been divided into “facies”. The below diagram is figure 2-2 in Spear’s 1993 book Metamorphic Phase Equilibria and Pressure-Temperature Time Paths. It shows some of the more common “facies” of metamorphic rock. Each facies is defined by a group of minerals that coexist in stable equilibrium in that range for a specific rock type. Therefore we metamorphic petrologists can tell just by looking at which minerals co-exist in a single rock roughly what sort of pressure and temperature the rock was at when the metamorphic minerals grew.

timing is everything

2010-08-12T08:07:00.001+10:00

I really should sit down and ready my 1000 words a day of geologic literature earlier in the day. Often what I read is inspiring and makes me want to go and do things for my own research. But, when I read it late at night, like tonight (and, I confess, many other nights as well), I’m too tired to follow through with the inspiration. Sadly, by the time I’ve slept and started a new day I’ve often forgotten the feeling of inspiration and nothing comes of it. Perhaps by stating this publicly I’ll revise my habit accordingly and gain the benefit thereby.

some pretty building stone in an unexpected location

2010-08-09T08:38:00.003+10:00

I have just returned from a four day visit to see friends who live in Ireland. I didn’t bring my computer along this trip, so I’ve returned to a fair bit of reading of e-mail/livejournal/blogs/facebook to catch up on. So I’ll just share this pretty building stone from a counter top in the Dublin airport. Lovely stuff, with plenty of garnet, definite foliation, some huge feldspar phenocrysts. No idea from whence it came, but it sure did brighten up the airport part of my adventure to see it.

Why Garnet?

2010-08-02T21:13:00.008+10:00

A friend of mine recently asked me “Why garnet?”, and it occurred to me that others might also like to hear one petrologist’s thoughts as to why it is such a well-studied metamorphic mineral.

1. They are pretty!

2. They are very common in a wide rang

e of metamorphic rock types.

3. They are stable across a reasonably broad range of pressures and temperatures of relevance for metamorphism.

4. The often form “porphyroblasts” (metamorphic crystals that are noticeably larger than those which surround them).

5. They are easy to identify in hand-samples—their nice “garnet-red” colour often contrasts with the other minerals in the sample (though some of the less common varieties come in other colours, including green and yellow).

6. They are easy to identify in thin-section (a slice of rock only ~3 microns thick, which means that light transmits through most of the minerals so that one can look at it in an optical microscope): they have a high “relief” (they look like they are taller than the things next to them, even though they aren’t) and they are isotropic (they are solid black when the polarizing filters are crossed, no matter how the stage is turned, making them stand out against the changing bright blues, pinks, and yellows that the other minerals become when the polarizing filters are crossed).

7. They have a rather broad range of possible chemical compositions, with iron, magnesium, manganese, and calcium all able to slot into the same position in the crystal structure (this is part of what gives it a broad range of stable temperatures and pressures) and aluminum and silica can also do a certain amount of swapping one for the other. There are a handful of other, less common elements which can also substitute for others in its crystal structure.

8. They have very slow diffusion, which means that once they reach a certain size the center of the grains no longer get involved in chemical reactions. As a result it is normal for the composition of garnets to be “zoned”, with the center containing more Mn than the rims, and the rims containing more Mg than the core (each of the other major elements also typically change their concentration from core to rim).

We metamorphic petrologists talk about the garnet cores being “armored” by the rims. The rims are, in theory, in equilibrium (or trying to achieve equilibrium) with the matrix minerals at any given time—this means that the minerals present will be participating in the chemical reactions that are causing the growth of some minerals and the dissolution of others. For many minerals the normal grain size is small enough that the reactions involve the entire grains, but garnets often grow large enough that only the outermost shell is involved in the reactions, with the inner portion “freezing” in whatever composition was stable when it was the outer portion.

So, just as an Everlasting Gobstopper (do they still make those candies?) changes colors as you suck on it, so garnets show a range of compositions from core to rim. Part of the changes in garnet composition are due to rare ingredients having been used up making garnet (plus or minus any other zoned minerals present). So Mn, which tends to prefer garnet to any other mineral in metamorphic rocks, starts out “high” in garnet, but there is usually so little of it available in any given metamorphic rock it is soon used up and the garnets have gradually less and less Mn as they grow, until eventually the outer portions have no measurable Mn at all. The other reasons garnets change their composition is due to changes in pressure or temperature. Different recipes of garnet are stable at different pressures and temperatures. So if the conditions change different types of garnet grow on the outside of the pre-existing garnet. These features all combine to make it a very well-studied mineral because of all of the inform

ation one can extract about the history of the rock.

A large garnet in the wild (southwest coast of Tasmania, photo taken by Andrew McNiel):

Garnets (2mm) in thin-section from Collingwood River, Tasmania (also shown are biotite (brown), muscovite (pale but wavy lines), quartz (colorless and without lines + dots in the garnet):

Same garnets as above, but in crossed-polarized light:

Achievements VS Tasks; writing for your audience when applying for a job

2010-07-31T22:47:00.004+10:00

Since my current contract ends in December, I’ve been watching the various geology email lists and job boards for interesting sounding jobs. Recently a friend of mine sent me a link to a position that isn’t in the academic world, but sounds like it would be fun, and I meet all of their “essential” requirements, though not necessarily all of their “desirable” ones, unless you take into consideration things I’ve done that are similar to what they are looking for.

However, this position has a much more formal application process than I underwent to obtain my current job. Their application packet makes it clear that a CV will not be considered, but instead we are instructed to fill in “details of your previous employment, starting with the most recent. Please include details of any time not accounted for (including unemployment)”. I had never had to compile a complete job history before, and it took a fair bit of time to remember everything I’ve ever done and fill in the boxes on the form (Date of employment, Name and address of Employer, Position held, description of main duties and responsibilities, achievements and reason/s for leaving). Once I’d completed that task and written my “Statement in Support of Application (Outline your reasons for applying and how your experience, knowledge and skills meet the job description, person specification and key competencies for the post. All the essential criteria must be covered)” I sent my completed form to my sister for comment.

While I have spent my life in Academia, my sister has been in the business world. She completed a Master’s in Education degree, but wound up going into corporate training rather than teaching at a school. She is also a writer (although I keep a blog, I don’t consider myself to be a writer; I’m a reader, who is willing to share thoughts via writing now and again). The feedback she gave me on my application packet was amazing—in just a few short paragraphs she captured the essence of one of the biggest problems I have in writing.

She had commented to me that I should delete some of the detail from my job list—that there is no need to show more than one job that happened at the same time, and no employer will care that I did modeling for a life drawing class while I was an undergraduate. I pointed out that I tend to err on the side of caution when deciding what information to include, and my brutally honest tendencies mean that I want to write down “everything”. To which she replied:

“Resumes and job apps are no different than any other type of writing: you must consider your audience and what they will be looking for, as well as your topic, angle, and goals for writing. That is, my guess is when you worked on a geology paper or presentation, you have more data points available to use than you actually include in your paper. That does not mean that you have been less than honest, or incomplete, it just means that you have likely chosen a specific idea to focus on, and analyzed, synthesized, and used the data that best informs that topic. Similarly, the level of depth and detail will vary if you're presenting to geologists in the same area of specialty to you, vs a broader field of geologist, vs a group of multi-disciplinary scientists, vs a room full of lay-people. In these situations, you would naturally think about who your audience is, the starting point they're at, what they would understand, and what might engage their interest.”

I laughed when I read this, thinking of the complaints I’ve heard people make about papers submitted for publication by recent PhD’s—that we tend to write papers that “read like a thesis”. In short we include too much information, wanting to share *everything* we learned in the course of our PhD projects. My first attempts at writing up my results certainly went that direction, and my advisor told me that it read too much like a thesis, and that I needed to go back and change it to the style of a paper. He even gave me papers I might use as a model. I’ve been putting off doing just that (it has been a year and a month since I submitted my thesis—my how time flies!), but reading my sister’s comments above, I think I may have a better handle on how to accomplish that goal.

My sister then went on to say:

“A resume or job application is only different in that it is a marketing document as much as it is a historical document. Its entire purpose is to get you to an interview. Anything that does not advance that purpose should not be included. Now, in the case of "list your entire work history and account for any gaps" listing all your experience does have a clear purpose. Still, you do get to decide how you present each item to make it relevant, or downplay it if it is not, as well as whether or not to include multiple items over the same time span. Also, you get to decide the "starting point" of your work history. Going back to a paper route when you were 9 years old is probably more information than the hiring manager needs to know (actually that was me with the paper route, but you get the idea).”

While I have long known the rule “write for your audience”, I don’t think I had *really* thought about what this meant in terms of job applications before. No wonder some of my applications never made it to the interview stage!

Her next paragraph included the gem “First, frame everything in terms of what you have achieved versus what you have done. (It's the difference between "managed the sales department" and "Improved sales by 40%" - or in your case between, "researched " to "published over xx papers, and conducted xx presentations on "” Re-writing my job history using this piece of advice has actually been quite fun—breaking up the information into the “duties” vs “achievements” has given me a whole new way of looking at it. Even if I don’t get the job for which I currently applying, the process of learning how better to apply for it has been so helpful I will still feel like I’ve won.

Reading Maps, or How I learned, yet again, that it is never safe to make assumptions

2010-07-29T09:07:00.000+10:00

When I was an undergrad enrolled in a Field Methods course my teacher wouldn’t even talk to us about the map unless we first “oriented” it (aligning the north arrow of the map with the north arrow of our compass). This is a very sensible idea, as one is much less likely to confuse one’s location by thinking that this hill on the map is that hill in the real world, when, really, it is the other hill over there. However, when printed in a book or posted onto a sign maps are often oriented with a “north at the top” convention.

Before today I would have used the word “always”, rather than “often”, but today I found out that the maps in Glasgow, Scotland are not oriented with north to the top. I have just spent a week visiting friends in Edinburgh (and enjoying the fact that the temperature was nice and cool—unlike southern Europe was before I left), and my return flight was out of the RyanAir airport in Prestwick (which is not that far from Glasgow). To get there from Edinburgh one takes a train to Glasgow Queen Street Station, and walks from there to the Glasgow Central Station to board the train to the airport.

I had thought about printing a map from google of Glasgow city centre before traveling, but forgot to do so before shutting down my computer. However, I didn’t worry about not having a map of my own, since I’d seen a Glasgow map and I knew that the two stations were quite close to one another; my destination is about two blocks west and 4 or 5 blocks south of the station to which I would be arriving. In addition to that information, my friend also told me that there are maps of Glasgow posted on signs in quite a few locations in the city center, especially near the train station, so I knew I could look this information up again when I got there.

When I arrived in Glasgow I exited the train station, looked around, and saw a map just up the street. When I reached the map I looked at the street signs for the intersection upon which I was standing to learn their names, then looked at the map (marked with a “you are here” arrow and a large circle of everything that the mapmaker thought was within a five minute walk of that point). Sure enough, the “you are here” spot was located at the intersection of the two streets whose signs I’d just read.

However, the bottom of the map ended only a couple of blocks below the “you are here” mark, just outside of afore mentioned large circle. Central Station was not visible at the bottom of the map (where I expected it to be, since I was using the assumption that the map was oriented with the top = north convention). Therefore I reasoned that the station I wanted is located just off of the area covered by the map, and I started down the street in what I assumed to be the correct direction.

One block later I found another sign with a map posted on it, but much to my surprise, there was still no Central Station at the bottom of the map. However, looking closer at the map I discovered that the station is on the map, but instead of being where I expected to find it, it was located near the top of the map.

A more careful perusal of the map in front of me revealed an over-street foot bridge located just above the “you are here” marker on the map. Looking past the map I saw that there is, in fact, such a foot bridge over the street in front of me. Ah-Ha! This map is not oriented “north = top”, it is oriented “top” = “direction you are facing as you look at the map”.

This prompted me to search the map for any sort of north arrow. There wasn’t one. Therefore, in order to determine that “up on the map” = “direction you are looking” one would need to either expect it to be so, or take time to do a careful comparison of the map with the real world. Fortunately, I’d only walked one block out of my way, so no harm was done, and I now know to take just a bit longer when reading maps posted in strange towns to see which convention (if any) they are using for how the maps are oriented.

What could be more fun than extending the boundaries of the sum of human knowledge?

2010-07-27T20:10:00.003+10:00

Not too long back I got into a conversation with a friend of mine, who was complaining about his job and how little he enjoys it. It is always difficult for me to be properly sympathetic in such conversations. Having learned as a child that “work” or “a job” meant "something unpleasant that people had to do but didn’t want to do", I have done my best to avoid ever having to do such a thing myself. Indeed, this was one of the largest motivating factors in my decision to be a life-long scholar—to stay happily in the academic world, learning interesting things.

When my academic career progressed to the point of undertaking a PhD project I was totally excited about it—I was about to learn something new, something that no one else ever knew before. This is heady stuff. Sure, there can be a fair bit of tedium in research, but that is more than offset by the ability to set one’s own hours and choose for oneself the topic and direction of the research. Having finished the PhD and moved on to a post-doc position doing experimental petrology I find that I am still expanding the bounds of human knowledge. The experiments I’m doing are ones that no one has done before—each run I do provides new information that needs to be analyzed—looked at, compared with the previous information, and understood.

I am aware that there are people out there who have the misfortune to spend their days doing things that don’t interest them, and I am grateful that I am not one of them—that I have the joy that comes from learning new things. Not just new to me, but new to everyone. What could be more fun than that?

re-finding motivation

2010-07-23T21:11:00.001+10:00

How much I accomplish on any given day depends upon a lot of factors. With the heat that has plagued southern Europe recently my motivation levels have been at a very low ebb. The longer the heat lasted, the less motivated I was to do anything near the computer (which generates its own heat, making matters worse). Eventually, in hopes of getting out of the cycle of thinking “I should be working, I’m too hot/miserable to work” I booked tickets to go visit a friend in Scotland for a week, thinking I could bring my computer and get more done while here than I’d been accomplishing at home, even with the distractions of a friend to visit.

Much to my delight, it is, in fact, much cooler here. This morning I enjoyed my first hot shower in weeks (it has been so hot that only very cold showers feel good at home). However, I then had to face a related challenge. One I am aware of, yet still get caught up in now and again. The dreaded “must work/can’t work” mentality often, for me, leads to “work” becoming a vague, nebulous, undefined thing that I “should” be doing, but am not. My first full day in Scotland I spent visiting friends, helping my friend get settled into his new flat, and baking bread and cookies. All with the vague sensation in the back of my mind that I “should” be working, but without any specific thoughts about what “work” means. I find it difficult to actually sit down to “work” when I don’t have a specific task in mind to accomplish.

Fortunately, late last night I took the time to actually open my files, see the list of tasks I have accomplished recently, and what more still needs doing, and I found a specific, identifiable task that needs to be done next. At that point I was much too sleepy to do it, but that is a good thing—this morning, when I woke up, I woke up thinking, for the first time in weeks, about work. About the specific things that need to be done next, so that I may compare the data I’ve been generating with the data that has been published in the literature. In short, I have re-found my motivation. So, with that I leave you and depart to my spreadsheets for an afternoon of fun with data…

today’s vocabulary lesson

2010-07-18T07:44:00.001+10:00

While reading my 1000 words of geologic literature today I encountered the sentence “However, these data may be the result of sampling mixtures of discrete fabric elements. Thus, the age of the older event is equivocal”. Since I was doing “active reading” (typing up a summary of each paragraph in my own words), I decided that I’d best actually look up “equivocal”, since while I *thought* I knew what it meant, I wasn’t willing to swear to it. So I checked the on-line Oxford English dictionary:

equivocal, a. and n.

A. adj.

1. Equal or the same in name (with something else) but not in reality; having a name, without the qualities it implies; nominal. Obs. (dates back to 1643)

2. Of words, phrases, etc.: Having different significations equally appropriate or plausible; capable of double interpretation; ambiguous. (dates back to 1601)

b. Of evidence, manifestations, etc.: Of uncertain bearing or significance. (dates back to 1969)

c. nonce-use. Of a person: Expressing himself in equivocal terms. (dates back to 1601)

3. Of uncertain nature; not admitting of being classified, ‘nondescript’. equivocal generation: the (supposed) production of plants or animals without parents; spontaneous generation. (dates back to 1658)

b. Of sentiments, etc.: Undecided, not determined to either side. Chiefly in negative sentences. (dates back to 1791)

c. Music. equivocal chord: one which may be resolved into different keys without changing any of its tones. (no date given)

4. Of advantages, merits, etc.: Dubiously genuine, questionable. (dates back to 1797)

5. Of persons, callings, tendencies, etc.: Doubtful in character or reputation; liable to unfavourable comment or description; questionable; suspicious. (dates back to 1790)

B. n. An equivocal word or term; a homonym. (dates back to 1653)

I find it fascinating that a word which comes to us from “equal” means “uncertain” (which, from the context, is the best match in this case).

My Dream Location

2010-07-08T21:17:00.003+10:00

The August Scientiae Carnival asks “what is going on in your life right now? What will be happening in six months or a year from now? What are your goals? Are you looking forward to the next year, or dreading it?”. This is a good time to be asking these questions of myself, since I have only six months remaining of my 1.5 year contract. I am starting to see jobs advertised with January start times, and have been re-vamping my CV and sending out applications and letters of enquiry. I’ve also been looking into the process of applying for funding, with the thought that while it is certainly easier to simply accept a job that is already funded, if I were to do my own funding application I would be able to work in a place of my own choosing doing a tasks that I want to do.

Where do I want to be in six months time? If I could have *everything* I want in life, I’d want to be doing research at a University located in a large town (or small city in the mountains). Someplace with a moderate to cold climate, and a winter where it not only snows, but the snow stays on the ground all winter. I’d want there to be plenty of hiking and cross-country ski trails in easy access from my home. I’d want an indoor rock-climbing gym at the Uni, located reasonably near my office. I’d want there to be a locally active branch of either the SCA or some other Medieval Reenactment organization that hosts camping events in the summer and has lots of music/singing/dancing at their winter events. I’d want my research to involve both field work and laboratory work and involve interesting metamorphic rocks that are pretty and have lots of information to convey. Does anyone know where this dream location is?

Marie Curie Conference

2010-07-03T03:27:00.002+10:00

I first heard about the post-doc position I now hold from an e-mail to the geo-metamorphic email list, and it wasn’t until I received a copy of the contract that I found out that by accepting the position I was becoming a Marie Curie Fellow. Since my very favorite book when I was a child was my copy of a children’s version of Madame Curie, a bibliography written in 1938 by her daughter Eve, I was quite delighted to find out that my funding is associated with such an amazing woman. Spending my childhood reading (over and over) about her love of learning, and how much she sacrificed in her youth to be able to attend University was probably a factor in my own love of learning and drive to attend University.

One of my favorite glimpses into her personality takes place after she has, after years of hard work, managed to isolate the element radium from pitchblende ore. Soon after that accomplishment was published she and her husband, Pierre, who had abandoned his own research to assist her with hers when he realized how important her work was, received a letter from a fellow scientist asking them to please share with him the details of the process so that he, too, could obtain pure radium for his studies. She and Pierre discuss it, acknowledging that since they invented the process they could charge people money to share the details. Had they gone that path they would have likely become quite rich thereby. However, they both agreed that in science it is far more important to freely share knowledge than to sell it—selling ideas was simply not appropriate in their minds.

I very much agree with them on this point. Consequently, the couple of hours of lectures at this week’s conference for Marie Curie Fellows (held in conjunction with the EuroScience Open Forum) which focused upon questions on intellectual property and the process of obtaining (and selling) patents rubbed me the wrong way. While I have no doubt that if Marie could know that there are 1000’s (I guess—there were over 400 of us at the conference) of people who are receiving funding to do research in other countries in her name she would feel honoured and delighted that so many talented scientists were getting such good opportunities, I also feel that she would not have approved of the message presented by those two speakers or who seemed, to me, to be equating science with an opportunity to gain financial profit.

potential calamity averted by a careful change in the erosional surface orientation

2010-06-28T20:50:00.000+10:00

My most recent experiment is one I’ve long been looking forward to analyzing—this is the highest-pressure run I’ve done yet. We gave it nearly 500 hours in the piston cylinder, while I was busy with lots of travel and a minor bout of food poisoning. Once we finally downloaded it and I rescued the capsules from their nest I discovered that they were stuck together. We always run two capsules (2 mm diameter gold tubes, welded shut around the experimental charge) in every experiment, with different compositions in each.

Usually it is enough to set them in the palm of my hand and rub them back and forth a bit to cause them to break apart before I carefully break off the last of the MgO, salt and graphite that clings to the capsules. This time they stayed stuck together no matter what I tried, so I consulted with my boss, who suggested that I try carefully grasping each with jeweler’s pliers and seeing if I can break them apart that way. Alas, they did not separate, instead one of the two capsules started to tear open.

Therefore I stopped trying and instead we put both capsules into a single epoxy mount. Knowing that it would require a fair bit of luck for the capsules to be oriented within the mount such that it would be possible to expose the insides of both capsules when I went to polish them I put off the task and spent the weekend visiting with friends. This morning I finally decided to look at the mount and try my hand a polishing them. When I looked I determined that the important ends of each capsule were not on the same plane with respect to the surface of the mount, but it looked like if I were careful to put more pressure on the one side than the other it might be possible to change the dip of the top of the mount such that both capsules were intersected. Much to my delight I managed to accomplish exactly this task. I now have one mount with two capsules, both exposed, all polished and turned in to be carbon-coated in preparation for tomorrow’s microprobe session.

This makes me very happy. I did not like the alternative, which would have been polish enough to expose one of the two, analyze and photograph everything in it and then polish it away to expose the other one for analysis. This way we will be able to go back and re-analyze anything we want at any time, rather than having one of them cease to exist in order to reach the other.

play with the data long enough and it becomes possible to find a way to see patterns in it

2010-06-16T09:14:00.007+10:00

One of the things I’ve been struggling with in my current research is how best to communicate the results from the various experiments I’ve run. My experiments have thus far yielded a total of ten different phases, with as many as seven of them appearing in a single experiment. I use two different capsules at each pressure and temperature at which I run experiments; each capsule has a different bulk composition. Therefore I’ve been displaying the result graphically, by using 8-pointed stars divided into an inner ring for one of the composition types, and an outer ring for the other. The resultant triangles representing the phases present are either left blank if it isn’t present or filled in with colour-coding if it is. One phase, quartz, is always present (save for when we reduce the starting SiO2 to eliminate it), so it doesn’t need a triangle of its own, and another occurs only in one high-P run, so it appears as a different colour triangle replacing one attached to a low-P phase; this is why I’ve been able to get away with using only eight points for the star.

However, there are times when it is necessary to communicate with text or a table, rather than with an illustration, and this is where I’d been stymied. I simply wasn’t seeing much in the way of a pattern with my data in terms of mineral assemblages. A mineral assemblage is the group of minerals which are all stable at the same pressure/temperature; they would have been the products of the reaction(s) which produced the assemblage. (When doing experiments we talk of phases rather than minerals—a phase is a particular composition of a mineral (many minerals can have more than one possible compositions, so may be considered a family of mineral phases)—in general only one phase within a family will be stable at a given set of conditions) .

Today I finally discovered a way to organize my data so as to see patterns in the assemblages. This required using colour coding and playing with the data, combining them into groups until I was able to determine that the “important” phases of the list of 10 are talc, garnet, and biotite. The others are either ubiquitous (quartz, chloritoid and muscovite) or only show up in a few of the runs and can be considered "minor" (zoisite, lawsonite, kyanite, carbonate). Once I’d worked that out, I was able to split the data into four groups each of which are +/- the minor phases and + the ubiquitous phases.

However, it was also necessary to consider each of the two bulk compositions separately to see the relationships between the groups, and I had to draw circles around the stars on my original P-T diagram to see how the groups relate to pressure and temperature. (I love having a drawing program which lets one draw circles on layers that can be made visible or invisible, so that one can see only the circles relevant to a single composition at one time.) Once I had all of the groups for each bulk composition circled it was easy to see that:

The experiments using the metagreywacke composition only have groups A, B, and C thus far. These groups plot on diagonal trends for this composition such that with respect to temperature B is less than both A and C, but with respect to pressure C is less than both B and A.

The experiments with metapelitic composition have groups A to D which plot in a grid such that with respect to temperature B is less than A while D is less than C and with respect to pressure C is less than A while D is less than B.

Now that I can see these patterns I shall really look forward to obtaining the results from future experiments to see how they relate to this overall pattern.

Anorthosite and asphalt

2010-06-06T07:44:00.004+10:00

I spent two days this week on a field trip in western Norway, where our guide assures us that the world’s best (ultra) high pressure rocks are located. It is my plan to do a proper field trip post, including photos, but in the mean time I’ll share with you a snippet of information I learned about one of the rock types we drove past, but did not stop at.

Near the town of Florø, Norway, there are a variety of white road cuts which are made of anorthosite. The primary (only?) mineral in anorthosite is plagioclase feldspar. In this area anorthosite is often quarried and used for making asphalt. Why? Several reasons:

* White colour of anorthosite makes whiter asphalt = better visibility for driving at night or under cloudy conditions.

* Plagioclase hardness (~6 on Mohs scale) makes for more durable, and therefore longer lasting asphalt.

* The plagioclase cleavage planes means that as cars drive on it and break it down the crystals maintain their edges, which provides better traction, even when wet.

Alas, I didn’t manage to get a photo of any of the anorthosite outcrops we passed—my camera has too long of a delay between pushing the button and taking a photo, which means that by the time I saw the outcrop it was too late to photograph it at the speeds our bus was traveling. But I was able to find a photo on line of an outcrop down near Bergen, which appears on this web page.

Barrow’s kyanite zone

2010-05-18T02:57:00.004+10:00

It has been a while since I made time to play in the Accretionary Wedge. This month the topic asks us to share (a) geologically significant photo(s). This announcement reminded me that I never did type up a summary of the field trip I did last year after the MAPT conference, so I’ll share a couple of photos from that trip, and explain why they are important.

The field trip went to look at the area Barrow made famous when he used it to formulate his theories on metamorphic facies. The Dalradian series is located just north of the Highland Boundary Fault in Scotland. Different parts of the series were metamorphosed at different pressures/temperatures, which resulted in different combinations of minerals in each area, though the composition of the rocks is similar.

In our field trip we started out near the fault, and stopped in each of the key areas along the way, visiting outcrops of the chlorite zone, the biotite zone, the carnet zone, and the kyanite zone. Most of the geologists on the trip are accustomed to looking at rocks in thin section, where, once you’ve learned how to identify them, it is a very easy matter to identify minerals and tell at a glance which zone the rocks come from. However, when Barrow did his field work in this area, he did it largely without thin sections—instead he looked at the rock outcrops themselves, and broke off pieces with his hammer and looked at them in the field.

The man was a talented enough petrologist that he was able to identify the minerals in the field, and to tell when he’d moved from one mineral assemblage to the next. Having spent a rainy day tramping around the lower part of the Scottish Highlands accompanied by geologists who knew in advance what minerals to expect in each outcrop, I still had difficulties spotting the index minerals in the outcrops. Or rather, I did, until we reached the kyanite zone. There is simply no mistaking the large blue crystals of kyanite in these rocks!

Book Review: The Fate of Nature

2010-05-17T22:55:00.002+10:00

Up until the arrival of social networking sites on line, the only reading I ever did (other than assignments for school work) was science fiction and fantasy novels. I happily spent much of my life with my nose buried in good book or another, enjoying the stories as they unfolds. I didn’t understand the appeal of non-fiction books, and didn’t even have interest in “literature”, as such, preferring to escape from this world by reading about life on other planets, or in other times—worlds wherein humans had risen past their baser natures and founded cooperative societies that didn’t destroy their environments. However, over the past few years I begun reading the journals my friends posted over on LiveJournal, and expanded from there to following a few well-written blogs, and using Facebook to get back into touch with various people I’ve met over the years.

One such person with whom I’ve become reacquainted was a man who graduated from the same high school I did, a few years before me. I can’t claim to have been amongst his close circle of friends, but I liked and admired the “big kids” of his generation, who were always busy—active in community involvement projects, or just having fun hanging out with one another. As a result when I heard that he’d written a book, I asked him to send me a copy.

The Fate of Nature, Rediscovering our Ability to Rescue the Earth, by Charles Wohlforth is, in many ways, completely and utterly unlike those SciFi novels I’ve so enjoyed over the years, and yet, I found myself entirely entranced by the book, reluctant to put it down each night so that I could sleep. This is a fascinating book blending science and history, full of detailed, very personal, stories about the individuals who have made a difference, both positive and negative, in Alaska over the years.

The amount of research that it must have taken to tell this story is really quite amazing. He chronicles the factors in Western culture, and their changes over time that resulted in people being willing to come into a new area (like Alaska) and remove from it such resources as they choose to, without any regard to any damage they might cause in the process, nor any plan to leave any for future generations. He cites studies that claim that the competitive nature is inherent to humans, and that given our drive for short-term personal gain there is no other option save eventual destruction of all of the ecosystems upon which we depend. But he doesn’t stop there—he cites other studies which show that again and again many humans choose cooperation and helping one another in favor of selfish gain. He shares the personal stories of the people who have worked tirelessly to save one aspect or another of the environment and how they have succeeded in their goals. He tells of the cultural changes that have taken place which result in policy changes which give him hope that it is not too late—that we, as a species may yet choose to protect and nurture our world.

Reading this book led me through a series of emotions, from depression and disgust (reading vivid details I never knew about what happened after the Exxon Valdez oil spill will do that) to uplifted sprits and joy at all that is positive in “human nature”. Reading the personal stories of the people who made it happen is fascinating. Knowing that this person, with whom I went to school when I was young, actually knows so many of these people reminds me of just how small this world is—they say that we are all connected within six degrees, but sometimes the connections are even closer than one might think.

I recommend reading this book to anyone who wants to understand more about the science (everything from global warming, to earthquake studies, to psychological studies, to biology, and more) behind living on earth, and the stories behind the facts in the history books. This book is for everyone who has ever thought “gee it would be nice if our time period isn’t one of an extinction period to rival that of the K-T boundary”.

some travel lulls are brief, indeed

2010-05-16T19:58:00.002+10:00

Having several days in a row wherein I’m not traveling has been good for me—I’ve actually been making progress transforming my PhD research into a paper, I’ve downloaded my most recent experiment and gotten it polished and ready to analyze with the microprobe on Tuesday, and I even made time to repair my trike, which had been damaged in shipping, so that I can ride it again, since the replacement wheel arrived when I was in Vienna for EGU.

However, this time it is only several days in a row—on Wednesday I’ve a meeting in Siena. I need to decide if I’m going to stay overnight and see something of the area, or simply day-trip (which would make for a long day, since it is a several hour train trip). Then I’ve only one more week to prepare for the trip to Norway for a meeting of our research group.

Try and try again

2010-05-12T03:01:00.000+10:00

Over the past couple of months I’ve been doing a fair bit of travel for conferences, short course, and writing workshop. Each meeting has been inspirational; each has resulted in additions to the list of things I want to accomplish in terms of research, data analysis, and writing papers for publication. However, the time I spend out of town for each of these meetings, combined with sight-seeing and exploring each new city ± time spent with friends at each location has meant that despite my inclination towards these tasks, the actual number of hours spent engaged in accomplishing them is distressingly low.

This is partially due to the amount of time it takes to arrange the logistics of travel—booking flights, arranging accommodation, packing, etc. and to the amount of time the travel itself takes up. Alas, my computer does not lend itself to in-flight use which so many fellow travelers accomplish—my computer has a battery which holds a charge long enough to properly shut down in case of a power-failure, but not for long enough to be worth turning the computer on unless I have somewhere I can obtain a steady stream of fresh electricity to keep the computer happy. For those of us flying budget airlines, this is not yet an option on flights. Likewise, returning home from a week spent elsewhere results in many urgent small tasks that need doing promptly after my return, all of which add up to not much progress being made on the above mentioned tasks inspired by the meetings.

Fortunately, other than one short trip during the week next week to finally meet in person the people with whom I collaborated on a paper a few years back, I’ve no trips planed until the end of the month. Therefore I state publicly here before you all that my goal is to not only get my next experiment downloaded, polished and ready for my scheduled microprobe analysis next week, but to also finish up at least one of the papers in progress and send it off to my erstwhile advisor for comment before submitting it. Readers who have been following my posts for a while might feel compelled to point out that I’ve stated that particular goal hitherto, but then gotten distracted preparing for upcoming talks on my current research. It is time to try again!

Conference ending; one last bike trip up the Danube before heading off

2010-05-07T23:40:00.001+10:00

Today was the final day of the EGU conference. It has been a very hectic, crowded week; on their web page they say “The EGU General Assembly 2010 was a great success with 4,431 oral and 9,370 poster presentations in 594 sessions. More than 10,000 scientists participated in the conference”. Now that most of the sessions are over the hall is quiet, and it is easy to find a table near an electrical outlet, and therefore to blog in comfort.

I spent the morning attending the session on Subduction zone dynamics: A slab's journey in the upper and lower mantle. Unsurprisingly, most of the talks had to do with numerical modeling of subduction—such a high percentage of them that one guy felt compelled to apologize for offering a talk based on geochemical data from real rocks. I, for one, was delighted to hear his talk—while the pretty pictures and movies of what may be happening in the subjection process is certainly interesting, hearing details about real rocks and what we can infer from their chemistry is even more interesting.

Now it is time for me to shut down the computer, enjoy one final bike-ride along the pretty bike path.

Comparing this weeks EGU meeting with December’s AGU meeting

2010-05-06T21:06:00.000+10:00

Having attended AGU in San Francisco in December, and being at EGU in Vienna this week, it is interesting to compare and contrast the two conferences. Both conferences offered the ability to create a “personal program” by browsing the web page or searching for specific key words, and clicking upon all talks/posters which sound interesting. Then with the push of one button it created a printout of everything I wished to attend, organized by day and time. I recall thinking at the time that AGU didn’t seem to have much of interest in the way of metamorphic or experimental petrology. Looking back on my personal program from that meeting, I count four talks and 26 posters on my personal program (plus two other talks on educational topics that I didn’t actually make it to). For EGU my personal program contains 27 talks and 60 posters.

Are there really that many more people in Europe working in fields which sound interesting to me, or have I become better at choosing search terms? Come to think of it, while I’ve not done a count, I have a vague impression that more of the authors of papers I’ve been reading are based in Europe, India, or Asia than in the US, so perhaps there really is a difference in focus between the two organizations.

One place where AGU excelled over EGU was the facilities they provided for internet access. Both organizations provided free wireless access, but AGU set up long tables and chairs, with power strips in sufficient quantity for everyone who wanted to use their own computer to do so without relying on battery power, and there were also cables available for internet access for those of us who preferred not to, or couldn’t use wireless. At EGU those of us who don’t have reliable computer batteries are limited to the occasional wall plug. While there are some low tables scattered near the food courts, very few of them happen to be within reach of wall plugs. As a result it is a common sight to see people sitting on the floor near an outlet, computer in lap. Occasionally one of the chairs will be dragged to an outlet to permit the electric-dependant computer user to sit in slightly greater comfort, but still with a computer on the lap. This explains why my posts are all lagging a day behind—while lap based internet access is sufficient for reading blogs or e-mail, it is not quite comfortable enough to encourage me to type. Therefore this is being typed sitting at a desk in the home of my host, and will be posted tomorrow, when I am back at the conference and once again have internet access.

My poster session at this meeting suffered from the same dearth of eager visitors as I experienced at AGU. While I could hear many conversations at most of the other posters in my range, most of the people on site who are interested in experiments on metapelitic compositions must have looked at the poster during the day when the author wasn’t present (as I did for all of the posters I wished to see). However, I did have one person come by and talk to me about my work—he has been doing isochemical section modeling for natural samples that include talc, and hasn’t been happy with the results he’s been getting. He uses Thermocalc (I know because his poster was on my list of things to see, so I went to look at it this morning, during a time when the author wasn’t present) and asked me about the Perplex activity model for talc. I looked it up and we discussed how my experiments aren’t very well predicted by Perplex. He commented that he thought that perhaps a non-ideal model would give us both better results matching the models with reality.

Yesterday at EGU

2010-05-04T23:18:00.002+10:00

Yesterday was the first day of EGU, the session on today’s schedule which came closest to matching my research interests was TS6.5/GD5.10/GMPV55, Ophiolites, blueschists and mélanges in convergent margin tectonics. I enjoyed the morning talks, and then checked out the vendors, where I found myself doing an impulse purchase. I now own a copy of Vernon’s Practical Guide to Rock Microstructure , a review of which is available here . I couldn’t resist the purchase, since it is full of pretty pictures of deformed rocks, and thoughts about what the physical expression of that deformation tells us about the processes which formed it.
After my shopping trip, there being no other sessions scheduled for the afternoon related to my research interest, I hoped onto my borrowed bicycle and enjoyed a lovely trip along the Danube bike path back to my friend’s house and took a much needed nap.
Now I need to get ready to attend my poster for the afternoon session, so I’ll post about today’s interesting talks tomorrow (no internet access where I’m staying). If you are at the meeting, I’ll be at XL192 from 17:00 to 19:00, come on by and say hello.

Pre-conference Adventures

2010-05-02T04:39:00.000+10:00

I am currently enjoying time playing tourist in Vienna before the EGU conference starts next week. I am very fortunate in that I’ve got a native guide to show me around and introduce me to her friends. I few years back I met a lady through an e-mail list for people who are interested in the clothing styles which were popular in the 12th Century. She posted a question about a costume she wanted to make, so I sent her the pattern I used when I did one in that style, and we began corresponding. I’ve long admired the photos she shares of her embroidery in her blog, and it is ever so much fun to see it in person, and to try on one another’s costumes.
She’s taken me fabric shopping, to museums, and to look at the early medieval stone carvings in the local cathedral and churches. She’s hosted a gathering of people to work on sewing projects tonight, and I am having much fun hanging out with like minded new friends. Tomorrow there will be more museums, and on Monday I’ll head to the conference and enjoy lectures on one of the other subjects which interest me. I understand we will have internet access on site, so I’ll try to post highlights of the talks during lunch breaks.
In the meantime I’m enjoying the fact that I can indulge two such very different sets of interest on one trip.

When you don’t understand something, look it up, even if it takes multiple sources

2010-04-27T19:56:00.006+10:00

I mentioned recently that I had a particularly good conversation at the last conference I attended. In follow up emails exchanged with the famous scientist in question he inquired if I’d complied a list talc-garnet occurrences and natural partitioning data. I actually had to ask him what he meant by that (the part about making a list of all of the published instances where talc-garnet occur (preferably in equilibrium) together was straightforward (answer: no, but I think that I will do so, it could be very useful), but I didn’t really understand what he meant by “natural partitioning data”. His reply further specified that he “was thinking of Fe/Mg (and possibly Mn) partitioning data between garnet and talc, in order to better constrain the HP phase relations”.

Ok, the word “partitioning” is English, and I kind of understand what he is saying, but I still wasn’t completly clear. Therefore I grabbed the dictionary of geologic terms I purchased back when I was an undergrad and looked it up. Not listed. Then I checked the index of Spear’s 1995 book. Not listed there either.

My next step was to look in an on-line dictionary of geologic terms. This one does list "partitioning method" ("A resistivity method in which a special electrode configuration is used, consisting of five electrodes, instead of the usual number of four, to provide a check on the observations"), but this is clearly not what he meant. It also lists "partition curve" ("A curve indicating, for each specific gravity (or size) fraction, the percentage that is contained in one of the products of the separation; e.g., the reject. Syn: distribution curve"), which is also not what he meant. Neither were any of the several definitions in the OED of any use.
Clearly, though the term is in general enough use amongst the metamorphic petrology community that he expected me to understand it, it isn’t yet showing up in the dictionaries.
Therefore I did a Scopus search for "Fe/Mg partitioning", and downloaded an article*, which might shed some light on the concept. Stay tuned for updates once I think I really understand what I think he meant…

*Sakai, T., Ohtani, E., Terasaki, H., Miyahara, M., Nishijima, M., Hirao, N., Ohishi, Y. and Sata, N. (2009). "Fe-Mg partitioning between post-perovskite and ferropericlase in the lowermost mantle." Physics and Chemistry of Minerals (volume in-press) 1-10.

New, improved list of mineral abbreviations

2010-04-23T05:06:00.002+10:00

I just found out about a newly published list of mineral names. A fairly high percentage of the geologic papers I’ve read have cited the 1983 paper by Kretz, Symbols For Rock-Forming Minerals, as a quick and easy way to state what they mean by the various abbreviations they used for mineral names, rather than wasting words in the paper stating that garnet is “Grt”, etc. However, 1983 is a rather long time ago, as far as papers are concerned, and that article listed only 193 minerals. Therefore I was delighted to hear about the newly published Abbreviations For Names of Rock-Forming Minerals by Whitney & Evans 2010. Their list expands on the 1983 list, giving us 371 mineral names to choose from (still only a drop in the bucket compared to the over 5,000 which are known, but this list includes the major rock-forming minerals). Like Kretz before them, they chose a format wherein all abbreviations consist of two or three letters (or rarely four if truly necessary to distinguish it from another). Unlike Kretz they also required that none of the mineral names conflict with the abbreviations used for elements of the periodic table (therefore, while they mostly keep the forms suggested in 1983, occasionally they changed them).
This expanded list will be very handy, and I’ve already copied it into an Excel spreadsheet and adjusted the formatting such that I can see the complete list on a single page.

inspiration found in someone else's adventure

2010-04-20T21:51:00.005+10:00

I try to maintain a positive approach to all that I do, but this lady is an inspiration to me. The author of that blog is a friend of a friend of mine (though we've never met), and I'm quite glad my friend pointed it out to me.

Word of the day

2010-04-20T19:36:00.003+10:00

While reading my 1000 words of Geologic Literature today I encountered a word with which I was unfamiliar: palimpsest.
According to the on-line Oxford English Dictionary the orginal sense of the word (when used as a noun) is as "Paper, parchment, or other writing material designed to be reusable after any writing on it has been erased. Obs."—this form dates back to 1616. By 1825 the word had evolved to mean "A parchment or other writing surface on which the original text has been effaced or partially erased, and then overwritten by another; a manuscript in which later writing has been superimposed on earlier (effaced) writing." By 1845 the word had also expanded to apply to "a thing likened to such a writing surface, esp. in having been reused or altered while still retaining traces of its earlier form; a multilayered record."
It has also been used (as early as 1876) specifically to refer to "A monumental brass plate turned and re-engraved on the reverse side. Cf. A. 2. Obs.". However, the most interesting uses to my mind are the geological senses of the word: "A structure characterized by superimposed features produced at two or more distinct periods." (1914) and "Of a rock structure: partially preserving the texture that existed prior to metamorphism." (1912). There are also geographical senses of the word: "Of a landscape or landform, esp. a glaciated topography or a drainage pattern: exhibiting superimposed features produced at two or more distinct periods."(1922).
It isn’t often that I encounter a word I don’t already know, and I find I rather enjoy it. There is something nice about being able to open a good on-line dictionary, paste in the new word, and be given not only the meanings, but dates for the earliest use of the word in that context that they could find. In this case I particularly like the development of the word over time first being limited to something humans make/use and re-use and then expanding to other categories. The rock record is full of instances where information is written upon pre-existing information to a greater or lesser degree. Our challenge, as geologists, is to correctly interpret each layer of information and take care not to confuse different layers of information with one another. Particularly when the layers of information may be recorded in so many varied manners.

Inspiring conversations

2010-04-15T03:39:00.004+10:00

I gave a talk at the EMPG conference this afternoon. As luck would have it, my talk was scheduled just before lunch. After I spoke one gentleman* came up with an additional question. We got to talking about my current research and my PhD research, and we wound up going to lunch together and then looking at photos from my thesis. He was interested in the Tasmanian whiteschist, having read about them years ago, and he enjoyed seeing my photos of them, and the graphs of the difference between the composition of the two different appearances of the garnet in that unit. The conversation lasted for the entire 1.5 hour lunch break. It was really enjoyable, and quite inspiring. I've already downloaded a handful of papers as a result of that conversation, and I look forward to reading them.

*Yes, his name is well-known in my field, no I hadn't met him hitherto, and yes, I have read and cited his papers.

another example of Geology in fiction

2010-04-09T08:38:00.002+10:00

I recently picked up a copy of Ender in Exile, by Orson Scott Card. Card is a writer I enjoy due to the quality of his writing, though I’m often infuriated by the philosophies espoused by some of his characters. This time the experience was, once again, mixed, with large parts of the story sucking me in and causing me to forget time was elapsing (and as a result staying up way too late at night/morning one evening), and the occasional narrow-minded pronouncement on the part of one of the characters causing me frustration that I wasn’t actually present for the conversation, and therefore am unable to explain to the speaker which points (s)he’s failing to take into consideration and why I think that their statement is in error.
However, one of the highlights for me with this book is the below quote, from
page 148 of the paperback edition (Tom Doherty Associates Publishers). To understand the quote you need to know that it is describing the observation of a place where a planet used to be, before it was completely destroyed by a “MD” field breaking apart all of its constitution atoms.

“Since the MD field broke everything into its constituent atoms, it is coalescing with remarkable quickness. Our observer ship has recently been in a position to see the dust cloud with the star directly behind it, and during the passage sufficient spectrometry and mass measurements were taken to assure us that the vast majority of the atoms have re-formed into the common, expected molecules, and that the gravity of the cloud was sufficient to hold most of the material in place. There has been some loss from escape velocity and further loss to solar gravity, solar wind, etc., but our best estimate is that the new planet will be at no less than 80 percent of the original mass, and perhaps more. At that size there will still be atmosphere, potentially breathable. There will also be molten core and mantle, ocean, and the probability of tectonic movement of thicker areas of crust-i.e. continents.

In short, while no artifacts of the former civilization can possibly be found, the planet itself will be back in a nice wad, in stellar orbit, within the next thousand years, and perhaps cool enough to explore in ten thousand years. Colonizable in a hundred thousand, if we seed it with oxygenating bacteria and other life as soon as the oceans are fully formed.”

Isn’t that a wonderful quote? Clearly the man has spent some time researching theories on the formation of planets, to have been able to write such a thing. It pleases me when part of the “Science” in a science-fiction book includes Geology!
What other fiction books have you read that do a reasonable job including geology (or in this case, I suppose, planetary science, since there aren’t any rocks, yet)?

Rest does wonders for one’s attention span, but you already knew that

2010-04-04T00:40:00.004+11:00

Rest does wonders for one’s attention span, but you already knew that

Having learned (once again) from yesterday’s mistake of putting off reading my 1000 words till I was sleepy, today I sat down and did it only four hours after I woke up. This is a much more sensible time of day to approach such a task. It felt much easier to do the reading and typing up of my notes, and what I read felt far more interesting than I remember yesterday’s reading, on the exact same topic, to have been. With luck I will remember this one for quite a while. However, the reality is that there are many, many things I wish to do with my time, and sometimes I choose to do one of them, and sometimes I choose to do one of the others. As a result it will eventually happen that I will choose to do other important tasks with my awake-energy and will once again have to choose between reading when I am sleepy or letting my run of consecutive days reading the 1000 words lapse. I’m at 87 days in a row, this time. Every time I manage to get that number up to these levels I become even more vested in continuing. My record thus far is 118 days in a row—that is only one more month. I would so very much like to pass that record. It would be fabulous to manage it for an entire year.

The below are my notes for the final 1000 words of Gordon et al. (2010)*. . It has been interesting, to me, to do this exercise, and to post my progress on a daily basis. I don’t expect anyone to have actually read my notes themselves, but perhaps my thoughts on the process are interesting to someone. Tomorrow’s 1000 words will be on a new paper

Paragraph 71 describes the fabrics (constrictional) on Elijah Ridge and mentions that the temperature for these rocks is slightly lower than on Ruby Mt. though they have similar pressures. It reiterates that before this study no evidence for high-P metamorphic conditions had been found east of the western end of this ridge, but this study found evidence on the eastern part of this ridge for an early high-P (8 kbars) consistent with Ruby Mt., the western part of this ridge, and with the deeper structural levels of the Skagit Gneiss. They conclude therefore that part of the Methow terrane in this region was buried to mid-crustal depths. They say that the late cordierite-andalusite overprint is likely due to contact metamorphism from the Golden Horn batholith (exposed 1< to the east) or other nearby plutons.

Paragraph 72 states that mapping failed to find the location of the RLFZ on Elijah Ridge or Ruby Mt., but that there is clearly a tectonic boundary between the oceanic Napeequa unit and the clastic meta-Methow rocks. The contact between these two units and the Skagit Gneiss is also tectonic, and in places where it is exposed to the north and the south is steeply dipping (> 70 degrees ), but here is it more gently dipping (35-45 degrees)

Paragraph 73 explains the above observations with a overlapping step-over zone in this region, with the units defining a duplex structure within the step-over zone. They indicate that the western fault zone is expressed as the shear zone on Ruby Mt. and the eastern part of the step-over is obscured by the Golden Horn Batholith and Ruby creek plutonic belt to the east. They relate the duplex with the NW end of the stepover and cite another paper which previously defined the stepover.

Paragraph 74 indicates that either the Napeequea originally (pre 65 Ma?) overlay the Skagit orthogneiss along a tectonic contact or the orthogneiss intruded into it, with some evidence for this early boundary showing in the shear zone on Ruby Mt. They provide two alternatives 1) the orthogneiss overlying the Napeequa unit on Ruby Mt. isn’t related to the Skagit Gneiss, and the deformation affected both the Napeequa and this orthogneiss after its emplacement or 2) it is related to the Skagit magmatism, intruding at the same time as the shear zone was active.

Paragraph 75 starts of with “in this model”, with nothing to indicate which of the many choices above is intended with the word “this”. It goes on to say that the step-over zone started during a transpressional regime, bringing together the Napeequa unit and some of the Methow basin rocks into a duplex with much crustal thickening, burring the lot, giving all three units a similar burial and exhumation history. The gradient of metamorphic grade in this region supports the notion that the Methow terrane was tilted, and the western end may have been structurally deep before the duplex (i.e. the strike-slip fault isn’t what buried these rocks to ~25 km, but it probably helped with some of the extra depth.

Paragraph 76 cites sources arguing for a change in the North Cascades at ~57 Ma from a transpressional to transtensional regime, which they say caused the extensional step-over and facilitated the exhumation of the mid-crustal rocks. They then cite another source which mentions imbrication along a pre-existing contact, and state that if that is the case then the Skagit gneiss had to have intruded into the Napeequa unit (and the orthgneiss above the Napeequa unit is part of the Skagit gneiss, just in a different spot because of that imbrication). The imbrication model includes the Methow basin rocks above the imbricated Skagit Gneiss and Napeequa units, which is compatible with the east dips of major contacts and foliation on Elijah Ridge.

Paragraph 77 States that both the step-over and imbrication models agree that there is a tectonic boundary on between Methow basin and Skagit Gneiss, and states that movement of the RLFZ is important to the relationship of these units. They cite sources saying that high T-deformation and activity continued till the early Tertiary.

Paragraph 78 states that since the Napeequa unit was not likely to have been in the upper crust at the time of deformation that they disagree with the hypothesis that the Skagit orthogneiss which is now directly under the Napeequa unit on Ruby Mt. was a flowing ductile crust underlying the non-flowing Napeequa unit. The then list again the evidence for both the Napeequa and Skagit rocks sharing metamorphic, deformational, and exhumation histories.

The final section break of the paper is here. The above section reviewed what was already known of the tectonometamorphic history of this area and indicated how their results add to that knowledge. The next section discusses the Exhumation of the Skagit Gneiss.

Paragraph 79 States that crustal thickening (> 30 km) and near isothermal decompression affected the Skagit Gneiss. They list the evidence for rapid cooling on exhumation around 57 to 45 Ma, when the North Cascades were in a transtensional regime and the RLFZ was dextral strike-slip combined with components of both reverse (pre 57 Ma) and normal (post 57 Mal) slip. Since the timing matches, they figure that the fault movement enhanced the exhumation.

Paragraph 80 states that the RLFZ incorporates different slices of the high grade and low-grade rocks in this region, and in some areas (specifically this field area) the basin rocks which are low-grade elsewhere were metamorphosed and deformed. This area is also the closest to the magmatic core of the Skagit Gneiss, so the partial melting could have weakened the crust and permitted the development of the step-over zone in this region. They state that this area is a good example of the relationships (they specify four) which develop in transtensional orogen. They state that the RLFZ is a strike-slip fault which accommodated and may even have initiated burial of sediments to mid-crustal depths and subsequent exhumation and the metamorphic rocks provide evidence which indicates a significant vertical component to strike-slip fault zones.

*Gordon, S.M., Whitney, D.L., Miller, R.B., McLean, N., and Seaton, N.C.A., 2010, Metamorphism and deformation at different structural levels in a strike-slip fault zone, Ross Lake fault, North Cascades, USA: Journal of Metamorphic Geology, 28, 117-136.

Active reading can even overcome sleepiness and result in comprehension

2010-04-03T09:43:00.002+11:00

I know better than to put off reading my 1000 words a day from the geological literature until late I the day, yet I chose to do so anyway. Today the impulse to do so was triggered by Spring. There were very few people in our geology department today, as most people chose to leave for their Easter long weekend as early as they could. Some of the general staff were here, but were only scheduled to be here till about 2:00 pm. Around the time that they were leaving I noticed that it was a beautiful day, nice and sunny, yet not hot at all, and I felt restless. Therefore I decided to head out on an adventure, and went into the city center to admire the street artists and musicians who perform for the crowds there. I also stopped in the American Book store and picked up a new book in a favourite series.

After these adventures I managed to limit myself to only an hour of reading in the new book before crossing the street to my office again around quarter to nine, intending to finish the work I’d interrupted hours before. Instead I procrastinated by catching up on reading blogs/e-mail/etc, updated my financial records to show today’s spending, and chatted with a friend on line. As a result I didn’t start reading my 1000 till 11:30 pm, and it was difficult to find the discipline I needed to actually complete the process.

However, hard as it was to make myself do, I am now a total convert to this “active reading” thing. The need to type the below notes meant that I had to actually pay attention to what I was reading, and not just sleepily skim over the words catching one in ten. I am positive that focusing on each paragraph one at a time and typing the notes as I go is the only thing that made it possible to understand what I was reading tonight. Perhaps I can understand and retain what I read the “normal” way when I’m high in energy, but this late in the day “active” reading is required. So, without further adieu, I give you the second-to-last installment of my paragraph-by-paragraph summary of the paper I’ve been reading (see a few days back for the citation and the link to the article itself).

The next section of the paper is on the 40Ar/39Ar results.

Paragraph 63 introduces the two pegmatites from which muscovite was obtained for the dating, describes the location of the pegmatites, gives the age results (~47.1 Ma for one and ~46.9 for the other). They state that the samples were obtained from above and below the contact, and are within error of one another. They state that this means that these numbers represent the time of cooling, rather than crystallization. This ends the section on the dating, and also concludes the section on their results. The next section is the Discussion.

Paragraph 64 points out that previous studies described a fault in this area and described the rocks on either side as high-grade on the west and low-grade the east, but this study indicates that what had been called “low grade” has actually undergone sufficient burial to achieve >650 C at 8-10 kbars, or largely the same as the “high grade” Gneiss. They go on to mention that the microstructures near the contact between the two units reveal progressive deformation & a high-T constrictional shear zone between the units, & subsequent overprinting by low-T deformation. They say that therefore this area is complex & important in context with the entire Cascades region, and for strike-slip dynamics in orogeny.

This concludes the lead-in portion of the discussion; the next section is on the Previous interpretations of Ruby Mt-Elijah Ridge tectonic history.

Paragraph 65 names three different studies which have addressed the tectonic history of this area. The first called this area a suture of Insular and Intermontane belts since it puts ocean rocks structurally above continental arc rocks. The second calls it a tectonized intrusive contact without a through-going fault, saying tilting is enough to expose the largely intact Mid-Cretaceous section, and add in one more fault to account for the change in pressure across the area. The third described this area as a major tectonic boundary, since there are mylonites present in addition to the difference in metamorphic pressures.

Paragraph 66 gives one other possible interpretation (calling this area the uppermost part of the flowing orogenic crust with the Napeequea unit acting as a rigid lid of a layered crust. They describe this interpretation as analogous to migmatite-upper crust relationships observed in the hinterland of the orogen, and cite a source (but from the sentence itself it isn’t clear if the source proposes this interpretation or simply describes the relationships in the analogy). They then state that all four models can be considered in light of their new data. This concludes the section on previous interpretations. The next section is the Re-evaluation of Ruby Mt-Elijah Ridge tectonometamorphic history.

Paragraph 67 describes the units in this area (orthogneiss dominating, Napeequea over it on Ruby Mt. and part (west end) of Elihah ridge, and Methow rocks above it on the east part), the dip (35-45 to the east) of the planar fabrics of bother Napeequea rocks and orthogneiss on Elijah Ridge while the far east side of the ridge is folded (= different deformation style across the ridge).

Paragraph 68 specifics that the low-T fabric overprinting migmatite seen in the microstructural analysis occurs only in the structurally deepest part of the exposed orthogneiss at the base of Ruby Mt. the only other units to show such overprint is the tonalitic amphibolite at the Skagit Gneiss-Napeequea contact .

Paragraph 69 contains too much information for one paragraph. It states that the strain gradient near the summit of Ruby Mt. displays more constrictional fabrics near the contact between the Skagit orthogneiss and Napeequea units (both of which are L-tectonites). It mentions the pegmatite which intrudes both that was deformed and cooled at ~47 Ma. It lists the clues which lead them to conclude that the shear zone is a medium- to high-T feature. It acknowledges some lower T-overprinting in a few of the units. It suggests rheologic contrast as the cause of the shear zone, but doesn’t decide between shear zone formation during or after emplacement of the orthogneiss. It suggests that the shear zone is an old contact which preserves the early high-T deformation of both units, further suggesting that the deformation either developed along or transposed the intrusive contact.

Paragraph 70 mentions the contacts between these units in other areas, the fact that the quartzite and schist of the Napeequa unit is generally more deformed than is the orthogneiss, suggesting that the composition of each is likely responsible for that difference. It then states that the contact exposed on Ruby Mt. is the one showing the most intense high strain fabrics.

This is not a section break. However, there are no more section breaks in this paper, save for the one which precedes the final paragraph, and I’m at 1000 words read today, and 1000 more left before the end of the paper. Therefore I’m going to stop here and pick it up with the next paragraph tomorrow.

getting faster

2010-04-02T08:26:00.002+11:00

I just read and took notes on the next section of the paper I’ve been “actively reading” for my 1000 words a day from the geologic literature, and am pleased to note that while I read well over 1000 (bringing yesterday’s and today’s combined total over 2000 words), it took just under 35 minutes to do so. I don’t know if this is because I’m becoming more comfortable with the process of active reading and typing up notes on each paragraph I read as I read them, or if these notes are less extensive than those for the earlier section, but I’m hopping it is just a matter of practice making me more efficient. I am willing to make 30 minutes a day, every day for this goal, but the over an hour I spent the first time I tried this technique might be asking a bit much.

I don’t know if anyone is actually reading the notes I’ve been posting, but I shall continue to post them till I reach the end of this article. If it should happen that someone tells me that the notes are interesting and/or helpful, I could easily be talked into continuing to post them for future articles I read, too. However, I suspect that for most people who are looking for interesting blogs to read one article summarized one paragraph at a time will be plenty. Feel free to let me know if I’m mistaken on that point.

Today’s notes are from the section on microstructural analysis:
Paragraph 53 introduces the locations from which the samples were collected for microstructural analysis and gives the goals for this portion of the study (understand mechanisms and relative timing of juxtaposition of the units)
Paragraph 54 mentions which samples were chosen for electron back scatter diffraction, gives details of what was found and compares and contrasts the results from the leucosome and mesosome layers of the sample. They go on to offer a tentative (since there weren’t enough samples analyzed to be confidant) interpretation (possible late shear zone affected the structurally deepest exposed rocks)
Paragraph 55 names a sample chosen for EBSD, reiterates that it is from the Skagit Gneiss), gives published U/Pb zircon age for this sample (which is younger than for other Skagit Gneiss samples), and describes the areas in this sample for which they made EBSD maps.
Paragraph 56 lists the results of the EBSD analysis for this sample (including strong crystallographic preferred orientation, prism slip for quartz (both regions of sample), sub grain rotation and recrystallisation (in shear zone), different grain sizes in different regions.
Paragraph 57 describes an effect (some qtz not deformed adjacent to larg plg grain) which only shows up in EBSD map, not via traditional optical methods. It also points out that such variety in qtz textures could indicate qtz deformed at all T and may have preserved evidence for more than one condition.
Paragraph 58 gives EBSD results for a new sample, from a new location.
Paragraph 59 mentions that the above sample has overprinting which doesn’t show up in higher parts of Ruby Mt. (instead the higher parts preserve high-T fabric with not much qtz recrystalization).
Paragraph 60 discusses textures in the structurally highest regions of Skagit Gneiss, and interpret them to indicate that the shear zone is a high-T feature.
Paragraph 61 more EBSD results this time for another couple of samples, comparing and contrasting them with each other, and with the other samples in the area. Interprets the results to indicate that the quartzite may have taken up much of the low-T deformation in this area
Paragraph 62 gives the EBSD results for samples from the RLFZ because they feel that understanding deformation in the fault zone will help interpretation of the role of the fault in burial and exhumation. They point out the similarities between these samples and the above.
Here ends the microstructural analysis section. I found it slightly hard to follow in terms of understanding which samples/areas were being discussed when, but that was because I hadn’t made notes about the sample names/locations in my pre-reading familiarization session. Nonetheless, I think that sub headings might have helped.
The next section will cover the 40Ar/39Ar results.