Wednesday 28 January 2009

Is it done yet?

Different people have different approaches to deadlines. Heck, many of us have multiple approaches to our own deadlines, depending upon what they are, who imposed them, and how crucial we see them to be at the moment. The two main approaches I tend to take with deadlines are been 1) turn it in before the deadline arrives or 2) undertake deadline-free projects.

As an undergraduate student I would usually start projects and assignments as soon as they were assigned, I always managed to turn in the assignment on the day it was due, and in the case of essays, I tended to have them “complete” with a few days to spare, so that I would have time to edit them before turning them in. In my historical recreation life I prefer the deadline-free approach. I am very fond of creating hand-sewn costumes which require much time to complete. Many of my friends, on the other hand, decide that they want a new costume for a specific upcoming event, and then spend many late hours the night before (or, often, every night for a week before) said event finishing up the costume “enough” to wear at the event. Not me, I prefer to approach my sewing with the attitude of “I need a project to work on at medieval reenactment events”. I then focus upon the process, taking care that my stitching is of the best quality, and enjoying the work for the peaceful relaxation which stems from doing the task, combined with enjoying the company of my friends while I stitch.

My approach to my PhD project has been a bit of a hybrid of the two attitudes. On the one hand, I am/have been putting in many hours of work, starting tasks as soon as possible after I am aware that they need doing. I always stop whatever else I have been working on to process the data straight away when I receive my microprobe results. I also continue to react to some sub-deadlines with my undergraduate approach. Each year I’d schedule my annual review meeting the first time they sent out the reminder that it was coming due, and would have mine done, turned in, and approval back from the University while the department was still sending out e-mails saying “some of you haven’t yet scheduled your annual reviews and need to do so soon”. When working on a paper in collaboration with others I generally sent back my edits/comments with 48 hours of receiving it from them.

However, there are other deadlines associated with a PhD project. These are the ones we set ourselves. In the annual review we are required to list our goals for what we will accomplish in the next year, and set dates by which these tasks will be accomplished. Each time I set these dates in consultation with my advisor, and each time, the tasks took longer than the amount of time set. I am now well past the first date associated with the task “submit thesis”, and only a week from the most recent date attached to that task, and still it is not ready to submit. The side of me which feels that deadlines exist so that we can have things done a week to three days before the deadline is somewhat twitchy about the relationship between the calendar and the various “submit thesis” deadlines I have failed to meet. On the other hand, the part of me which cares more about doing a task well, and because it is worth doing, and not because of deadlines, is happily puttering along, enjoying what I’m learning, content in the progress I’ve made. Which should I listen to? The stressed out “you are late” voice in my ear, or the “this is interesting, and wait, you haven’t looked at the data *this* way yet…” voice in the other ear?

I commented to my advisor yesterday that working on a PhD project seems to be a lesson in how not to meet deadlines, no matter how punctual one has been hitherto. He replied that in a three week project, if one gets 10% behind schedule, one can give up one day of the weekend, put in a long day, and catch up, but on a three year project if one gets 10% behind one day of hard work will not be enough to catch back up. Am I behind? It has been 3.6 years since I started this project. The Australian University system says that three years is how long a PhD project “should” take, and that if you ask nicely and show that the delays are due to circumstances beyond your control they will fund you for 3.5 years. So, the question really is, do I believe them? Is that really an appropriate amount of time to make the transition from “knowing little to nothing about metamorphic petrology” to “doctor of philosophy and expert of this tiny sub-set of metamorphic petrology as applied to this tiny portion of the planet”? Perhaps it is. Perhaps they are unrealistic in their time limits. Or, perhaps, they deliberately set impossible deadlines because they have found that in the old days, when PhD projects were meant to take four years, people took seven to ten, but now that they say we may have only three years, people tend to take about four.

Friday 23 January 2009

What I’ve been reading

A number of my friends have been doing a “50 books in a year” challenge, wherein they try to make time to read 50 books over the course of a calendar year. Not surprisingly, this month they have all been posting their results for the past year.

For all of my life I’ve been an avid reader of science fiction/fantasy books, and whilst I didn’t keep a list, if anyone had told me that I would be limited to reading *only* 50 books in a year, I’d have been traumatized. However, when I started my PhD project I suspected that I’d have to cut back on my reading of fiction in order to make more time for my research. Therefore I started keeping a list of what I read, and how long it took me to read it. The first full year of my PhD project, I read 61 fiction books, and I am quite certain that is less than had been normal for me. The second full year of my PhD project I also read 61 fiction books. The third year I managed only 46, and now that I’m ticking away on the fourth (unfunded) year, I’ve managed 15 fiction books so far, which means that if my rate of reading remains unchanged for the rest of the time period (and I were so unfortunate as to stretch the degree out to four full years, instead of the anticipated 3.75), I would read only 21 fiction books over the course of the year.

How is this possible? How can an avid reader cut so far back on their literary intake and maintain their sanity? The answer is that I’m still reading. I’m just not making much time to read fiction. Some of my reading takes the form of following blogs/livejournal/facebook/myspace to keep track of the doings of old friends, new friends, and friends I’ve not yet met. This tends to be done in short 5-30 minute breaks from working, while I’m sitting at the computer. However, by far most of my reading has been geologic literature. Switching my count from “years enrolled in a PhD Project” to “calendar year” (I started in June of 2005, so my years are about six months out) I have read two geology text books cover to cover (Spear, 1993 Metamorphic phase equilibria and pressure-temperature-time paths, and Spry, 1969 Metamorphic Textures) and 73 abstracts of papers which I either put onto the “to read” list, or, in some cases, decided I didn’t need to read, and 141 papers read in full (or, in a few cases, read closely in part, and skimmed the rest). Here follows the list of the papers I read in full between 1 Jan and 31 Dec 2008. It is an interesting mix of topics, not all of which relate directly to my own research:

Akinin, V. V., Miller, E. L. and Wooden, J. (in press (copy recieved from E. L. Miller August 2008)). Petrology and Geochronology of Crustal Xenoliths from the Bering Strait Region: Linking Deep and Shallow Processes in Extending Continental Crust. to be submitted to GSA book on “Crustal cross-sections from the western North America Cordillera and elsewhere: Implications for tectonic and petrologic processes”. R. B. M. a. A. W. Snoke.

Al-Wardi, M. and Butler, R. W. H. (2007). "Constrictional extensional tectonics in the northern Oman mountains, its role in culmination development and the exhumation of the subducted Arabian continental margin." Geological Society Special Publication: 187-202.

Berry, R. F. and Crawford, A. J. (1988). "The tectonic significance of Cambrian allochthonous mafic-ultramafic complexes in Tasmania." Australian Journal of Earth Sciences 35(4): 523-533.

Berry, R. F. and Gray, D. R. (2001). The Structure of the Coastal Section from Goat Island to Ulverstone, Northwestern Tasmania. Specialist Group in Tectonics and Structural Geology Field Guide 10, University of Tasmania.

Berry, R. F., Jenner, G. A., Meffre, S. and Tubrett, M. N. (2001). "A North American provenance for Neoproterozoic to Cambrian sandstones in Tasmania?" Earth and Planetary Science Letters 192(2): 207-222.

Berry, R. F., Steele, D. A. and Holm, O. H. (2005). "Chemical U-Th-Pb monazite dating and the Proterozoic history of King Island, southeast Australia." Australian Journal of Earth Sciences 52(3): 461-471.

Berry, R. F., Steele, D. A. and Meffre, S. (in press 2008). "Proterozoic metamorphism in Tasmania: Implications for tectonic reconstructions." Precambrian Research.

Bhattacharya, A., Mohanty, L., Maji, A., Sen, S. K. and Raith, M. (1992). "Non-ideal mixing in the phlogopite-annite binary: constraints from experimental data on Mg-Fe partitioning and a reformulation of the biotite-garnet geothermometer." Contributions to Mineralogy and Petrology 111(1): 87-93.

Black, L. P., Oversby, B. S., Bain, J. H. C., Withnall, I. W. and Gregory, P. (2005). "U-Pb zircon ages from leucogneiss in the Etheridge Group and their significance for the early history of the Georgetown region, north Queensland." Australian Journal of Earth Sciences 52(3): 385-401.

Black, L. P., Seymour, D. B., Corbett, K. D., Cox, S. E., Streit, J. E., Bottrill, R. S., Calver, C. R., Everard, J. L., Green, G. R., McClenaghan, M. P., Pemberton, J., Taheri, J. and Turner, N. J. (1997). Dating Tasmania's Oldest Geological Events. Mineral Resources Tasmania, Australian Geological Survey Organisation. 1997/15 57 pp

Boger, S. D. and Miller , J. A. (2004). "Terminal suturing of Gondwana and the onset of the Ross-Delamerian Orogeny: The cause and effect of an Early Cambrian reconfiguration of plate motions." Earth and Planetary Science Letters 219(1-2): 35-48.

Bousquet, R., El Mamoun, R., Saddiqi, O., Goffe, B., Möller, A. and Madi, A. (2008). "Mélanges and ophiolites during the Pan-African orogeny: The case of the Bou-Azzer ophiolite suite (Morocco)." Geological Society Special Publication(297): 233-247.

Caddick, M. J. and Thompson, A. B. (2008). "Quantifying the tectono-metamorphic evolution of pelitic rocks from a wide range of tectonic settings: Mineral compositions in equilibrium." Contributions to Mineralogy and Petrology 156(2): 177-195.

Calligaro, T. (2008). "PIXE in the study of archaeological and historical glass." X-Ray Spectrometry 37(2): 169-177.

Calligaro, T., Colinart, S., Poirot, J. P. and Sudres, C. (2002). "Combined external-beam PIXE and ?-Raman characterisation of garnets used in Merovingian jewellery." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 189(1-4): 320-327.

Campana, B. and King, D. (1963). "Palaeozoic tectonism, sedimentation and mineralization in West Tasmania." Australian Journal of Earth Sciences 10(1): 1 - 53.

Carlson, W. D. (1989). "The significance of intergranular diffusion to the mechanisms and kinetics of porphyroblast crystallization." Contributions to Mineralogy and Petrology V103(1): 1-24.

Carlson, W. D. (2006). "Rates of Fe, Mg, Mn, and Ca diffusion in garnet." American Mineralogist 91(1): 1-11.

Cawood, P. A. (2005). "Terra Australis Orogen: Rodinia breakup and development of the Pacific and Iapetus margins of Gondwana during the Neoproterozoic and Paleozoic " Earth-Science Reviews 69(3-4): 249-279.

Cawood, P. A. and Korsch, R. J. (2008). "Assembling Australia: Proterozoic building of a continent." Precambrian Research 166(1-4): 1-35.

Cayley, R. A., Taylor, D. H., VandenBerg, A. H. M. and Moore, D. H. (2002). "Proterozoic - Early palaeozoic rocks and the Tyennan Orogeny in central Victoria: The Selwyn Block and its tectonic implications." Australian Journal of Earth Sciences 49(2): 225-254.

Cheeney, R. F. (2002). "Charles Lapworth’s mylonites." Scottish Journal of Geology 38(1): 1-3.

Cirrincione, R., Ortolano, G., Pezzino, A. and Punturo, R. (2008). "Poly-orogenic multi-stage metamorphic evolution inferred via P-T pseudosections: An example from Aspromonte Massif basement rocks (Southern Calabria, Italy)." Lithos 103(3-4): 466-502.

Clark, C., Schmidt Mumm, A. and Faure, K. (2005). "Timing and nature of fluid flow and alteration during Mesoproterozoic shear zone formation, Olary domain, South Australia." Journal of Metamorphic Geology 23(3): 147-164.

Corbett, K. D., Banks, M. R. and Jago, J. B. (1972). "Plate tectonics and the Lower Palaeozoic of Tasmania." Nature Physical Science 240: 9-11.

Corbett, K. D. and Lees, T. C. (1987). "Stratigraphic and structural relationships and evidence for Cambrian deformation at the western margin of the Mt Read Volcanics, Tasmania." Australian Journal of Earth Sciences 34(1): 45 - 67.

Crook, K. A. W. (1980). "Fore-arc evolution in the Tasman Geosyncline: The origin of the southeast Australian continental crust." Australian Journal of Earth Sciences 27(1): 215 - 232.

Dahl, P. S., Hamilton, M. A., Jercinovic, M. J., Terry, M. P., Williams, M. L. and Frei, R. (2005). "Comparative isotopic and chemical geochronometry of monazite, with implications for U-Th-Pb dating by electron microprobe: An example from metamorphic rocks of the eastern Wyoming Craton (U.S.A.)." American Mineralogist 90(4): 619-638.

Dasgupta, S., Sengupta, P., Guha, D. and Fukuoka, M. (1991). "A refined garnet - biotite Fe-Mg exchange geothermometer and its application in amphibolites and granulites." Contributions to Mineralogy and Petrology 109(1): 130-137.

Duncan, D. M. (1972). "Reconnaissance Geology of the Frenchmans Cap National Park." The Papers and Proceedings of the Royal Society of Tasmania 107.

Elliott, C. G., Woodward, N. B. and Gray, D. R. (1993). "Complex regional fault history of the Badger Head region, northern Tasmania." Australian Journal of Earth Sciences 40(2): 155 - 168.

Elliston, J. (1954). Regional geological survey - Lorinna. Mineral Resources Tasmania. UR1954_091_107

England, P. C. and Thompson, A. B. (1984). "Pressure-temperature-time paths of regional metamorphism I. Heat transfer during the evolution of regions of thickened continental crust." Journal of Petrology 25(4): 894-928.

Farges, F. (1998). "Mineralogy of the Louvres Merovingian garnet cloisonné jewelry: Origins of the gems of the first kings of France." American Mineralogist 83(3-4): 323-330.

Faryad, S. W. and Chakraborty, S. (2005). "Duration of Eo-Alpine metamorphic events obtained from multicomponent diffusion modeling of garnet: A case study from the Eastern Alps." Contributions to Mineralogy and Petrology 150(3): 306-318.

Fazio, E., Cirrincione, R. and Pezzino, A. (2008). "Estimating P-T conditions of alpine-type metamorphism using multistage garnet in the tectonic windows of the Cardeto area (southern Aspromonte Massif, Calabria)." Mineralogy and Petrology 93(1-2): 111-142.

Feenstra, A., Petrakakis, K. and Rhede, D. (2007). "Variscan relicts in Alpine high- P pelitic rocks from Samos (Greece): Evidence from multi-stage garnet and its included minerals." Journal of Metamorphic Geology 25(9): 1011-1033.

Ferry, J. and Spear, F. S. (1978). "Experimental calibration of the partitioning of Fe and Mg between biotite and garnet." Contributions to Mineralogy and Petrology 66(2): 113-117.

Finger, F. and Krenn, E. (2007). "Three metamorphic monazite generations in a high-pressure rock from the Bohemian Massif and the potentially important role of apatite in stimulating polyphase monazite growth along a PT loop." Lithos 95(1-2): 103-115.

Fioretti, A. M., Black, L. P., Foden, J. and Visonà, D. (2005). "Grenville-age magmatism at the South Tasman Rise (Australia): A new piercing point for the reconstruction of Rodinia." Geology 33(10): 769-772.

Foden, J., Elburg, M. A., Dougherty-Page, J. and Burtt, A. (2006). "The timing and duration of the Delamerian orogeny: Correlation with the Ross Orogen and implications for Gondwana assembly." Journal of Geology 114(2): 189-210.

Foden, J., Song, S. H., Turner, S., Elburg, M., Smith, P. B., Van der, S. and Van Penglis, D. (2002). "Geochemical evolution of lithospheric mantle beneath S.E. South Australia." Chemical Geology 182(2-4): 663-695.

Foster, D. A., Gray, D. R. and Spaggiari, C. (2005). "Timing of subduction and exhumation along the Cambrian East Gondwana margin, and the formation of Paleozoic backarc basins." Geological Society of America Bulletin 117(1): 105-116.

Gaidies, F., Abart, R., De Capitani, C., Schuster, R., Connolly, J. A. D. and Reusser, E. (2006). "Characterization of polymetamorphism in the Austroalpine basement east of the Tauern Window using garnet isopleth thermobarometry." Journal of Metamorphic Geology 24(6): 451-475.

Gaidies, F., de Capitani, C. and Abart, R. (2008). "THERIA_G: a software program to numerically model prograde garnet growth." Contributions to Mineralogy and Petrology 155(5): 657-671.

Gaidies, F., de Capitani, C., Abart, R. and Schuster, R. (2008). "Prograde garnet growth along complex P-T-t paths: results from numerical experiments on polyphase garnet from the Wölz Complex (Austroalpine basement)." Contributions to Mineralogy and Petrology 155(6): 673-688.

Gaidies, F., Krenn, E., De Capitani, C. and Abart, R. (2008). "Coupling forward modelling of garnet growth with monazite geochronology: An application to the Rappold Complex (Austroalpine crystalline basement)." Journal of Metamorphic Geology 26(7): 775-793.

García-Sansegundo, J., Farias, P., Gallastegui, G., Giacosa, R. E. and Heredia, N. (2008). "Structure and metamorphism of the Gondwanan basement in the Bariloche region (North Patagonian Argentine Andes)." International Journal of Earth Sciences check back on this one later--it was still "in press' when I downloaded it: 1-10.

Gibson, H. D., Carr, S. D., Brown, R. L. and Hamilton, M. A. (2004). "Correlations between chemical and age domains in monazite, and metamorphic reactions involving major pelitic phases: An integration of ID-TIMS and SHRIMP geochronology with Y-Th-U X-ray mapping." Chemical Geology 211(3-4): 237-260.

Goodge, J. W., Williams, I. S. and Myrow, P. (2004). "Provenance of Neoproterozoic and lower Paleozoic siliciclastic rocks of the central Ross orogen, Antarctica: Detrital record of rift-, passive-, and active-margin sedimentation." Bulletin of the Geological Society of America 116(9-10): 1253-1279.

Gray, D. R., Miller, J. M. and Gregory, R. T. (2005). "Strain state and kinematic evolution of a fold-nappe beneath the Samail Ophiolite, Oman." Journal of Structural Geology 27(11): 1986-2007.

Green, G. R. (1983). The geological setting and formation of the Rosebery volcanic-hosted massive sulphide orebody, Tasmania. Hobart, University of Tasmania.

Guerra, M. F., Calligaro, T. and Perea, A. (2007). "The treasure of Guarrazar: Tracing the gold supplies in the Visigothic Iberian Peninsula." Archaeometry 49(1): 53-74.

Hannula, K. A., Miller, E. L., Dumitru, T. A., Lee, J. and Rubin, C. M. (1995). "Structural and metamorphic relations in the southwest Seward Peninsula, Alaska: crustal extension and the unroofing of blueschists." Geological Society of America Bulletin 107(5): 536-553.

Harris, D. H. M. (1995). "Caledonian transpressional terrane accretion along the Laurentian margin in Co. Mayo, Ireland." Journal - Geological Society (London) 152(5): 797-806.

Henry, D. J., Guidotti, C. V. and Thomson, J. A. (2005). "The Ti-saturation surface for low-to-medium pressure metapelitic biotites: Implications for geothermometry and Ti-substitution mechanisms." American Mineralogist 90(2-3): 316-328.

Henson, P. (2002). Geology of the Port Sorell Formation. Earth Sciences. Hobart, University of Tasmania.

Hetherington, C. J. and Le Bayon, R. (2005). "Bulk rock composition: A key to identifying invisible prograde reactions in zoned garnet." Schweizerische Mineralogische und Petrographische Mitteilungen 85(1): 57-67.

Hirsch, D. M. (2008). "Controls on porphyroblast size along a regional metamorphic field gradient." Contributions to Mineralogy and Petrology 155(4): 401-415.

Holdaway, M. J. and Lee, S. M. (1977). "Fe-Mg cordierite stability in high-grade pelitic rocks based on experimental, theoretical, and natural observations." Contributions to Mineralogy and Petrology 63(2): 175-198.

Holdaway, M. J., Mukhopadhyay, B., Dyar, M. D., Guidotti, C. V. and Dutrow, B. L. (1997). "Garnet-biotite geothermometry revised: New Margules parameters and a natural specimen data set from Maine." American Mineralogist 82(5-6): 582-595.

Holland, M., Urai, J. L. and Martel, S. (2006). "The internal structure of fault zones in basaltic sequences." Earth and Planetary Science Letters 248(1-2): 286-300.

Holland, T. and Powell, R. (2000). AX-Activity-Composition Software, Department of Earth Sciences, University of Cambridge.

Holm, O. H. and Berry, R. F. (2002). "Structural history of the Arthur Lineament, northwest Tasmania: an analysis of critical outcrops." Australian Journal of Earth Sciences 49(2): 167-185.

Hoschek, G. (2004). "Comparison of calculated P-T pseudosections for a kyanite eclogite from the Tauern Window, Eastern Alps, Austria." European Journal of Mineralogy 16(1): 59-72.

Inui, M. (2008). "A thin-section scale original inhomogeneity of bulk rock chemistry inferred from compositional zoning of garnet in the Sambagawa metamorphic rocks, central Shikoku, Japan." Journal of Mineralogical and Petrological Sciences 103(2): 135-140.

Johnson, M. R. W. (1967). "Mylonite Zones and Mylonite Banding." Nature 32(5073): 246-247.

Keid, H. G. W. (1944). Geological report on Port Davey Area. Mineral Resources Tasmania. UR1944_031_33

Krenn, E., Ustaszewski, K. and Finger, F. (2008). "Detrital and newly formed metamorphic monazite in amphibolite-facies metapelites from the Motajica Massif, Bosnia." Chemical Geology 254(3-4): 164-174.

Lapworth, C. (1885). "The Highland Controversy in British Geology: its Causes, Course, and Consequences." Nature 32(832): 588-589.

Li, Z. X., Baillie, P. W. and Powell, C. M. (1997). "Relationship between northwestern Tasmania and East Gondwanaland in the Late Cambrian/Early Ordovician: Paleomagnetic evidence." Tectonics 16(1): 161-171.

Marmo, B. A., Clarke, G. L. and Powell, R. (2002). "Fractionation of bulk rock composition due to porphyroblast growth: Effects on eclogite facies mineral equilibria, Pam Peninsula, New Caledonia." Journal of Metamorphic Geology 20(1): 151-165.

Martin, A. J., Gehrels, G. E. and DeCelles, P. G. (2007). "The tectonic significance of (U,Th)/Pb ages of monazite inclusions in garnet from the Himalaya of central Nepal." Chemical Geology 244(1-2): 1-24.

Massonne, H. J. and Sobiech, M. (2007). "Paragonite: Why is it so rare in medium-temperature high-pressure rocks?" International Geology Review 49(4): 301-312.

Mathavan, V. and Bowes, D. R. (2004). "Microstructural features of albite porphyroblasts as indicators of sequential Barrovian metamorphic mineral growth in the Caledonides of the SW Scottish Highlands." Journal of Metamorphic Geology 22(7): 639-651.

Meffre, S., Berry, R. F. and Hall, M. (2000). "Cambrian metamorphic complexes in Tasmania: tectonic implications." Australian Journal of Earth Sciences 47(6): 971-985.

Meth, C. E. and Carlson, W. D. (2005). "Diffusion-controlled synkinematic growth of garnet from a heterogeneous precursor at Passo del Sole, Switzerland." Canadian Mineralogist 43(1): 157-182.

Miller, E. L., Calvert, A. T. and Little, T. A. (1992). "Strain-collapsed metamorphic isograds in a sillimanite gneiss dome, Seward Peninsula, Alaska." Geology 20(6): 487-490.

Miller, J. M., Gray, D. R. and Gregory, R. T. (2002). "Geometry and significance of internal windows and regional isoclinal folds in Northeast Saih Hatat, Sultanate of Oman." Journal of Structural Geology 24(2): 359-386.

Münker, C. and Crawford, A. J. (2000). "Cambrian arc evolution along the se gondwana active margin: A synthesis from Tasmania-New Zealand-Australia-Antarctica correlations." Tectonics 19(3): 415-432.

Nakamura, D. and Hirajima, T. (2005). "Experimental evaluation of garnet-clinopyroxene geothermometry as applied to eclogites." Contributions to Mineralogy and Petrology V150(6): 581-588.

Noll, C. A. and Hall, M. (2005). "Great Lyell Fault, western Tasmania: A collage of Middle and Late Cambrian growth faults reactivated during Devonian orogenesis." Australian Journal of Earth Sciences 52(3): 427-442.

Palmeri, R., Chmielowski, R. M., Sandroni, S., Talarico, F. and Ricci, C. A. (in press). "Petrology of the eclogites from western Tasmania: Insights to the Cambro-Ordovician evolution of the paleo-Pacific margin of Gondwana." Lithos.

Pan, Y. and Fleet, M. E. (2002). Compositions of the apatite-group minerals: Substitution mechanisms and controlling factors. Reviews in Mineralogy and Geochemistry: Phosphates: Geochemical, Geobiological, and Materials Importance. M. J. Kohn, J. Rakovan and J. M. Hughes. Washington, DC, Mineralogical Society of America. 48: 13-49.

Pappalardo, L., Karydas, A. G., Kotzamani, N., Pappalardo, G., Romano, F. P. and Zarkadas, C. (2005). "Complementary use of PIXE-alpha and XRF portable systems for the non-destructive and in situ characterization of gemstones in museums." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 239(1-2): 114-121.

Patel, S. C., Ravi, S., Anilkumar, Y., Naik, A., Thakur, S. S., Pati, J. K. and Nayak, S. S. (2009). "Mafic xenoliths in Proterozoic kimberlites from Eastern Dharwar Craton, India: Mineralogy and P–T regime." Journal of Asian Earth Sciences 34: 336-346.

Powell, R. and Holland, T. (1994). "Optimal geothermometry and geobarometry." American Mineralogist 79(1-2): 120-133.

Powell, R. and Holland, T. (2008). "On thermobarometry." Journal of Metamorphic Geology 26(2): 155-179.

Powell, R., Holland, T. and Worley, B. (1998). "Calculating phase diagrams involving solid solutions via non-linear equations, with examples using THERMOCALC." Journal of Metamorphic Geology 16(4): 577-588.

Pyle, J. M. and Spear, F. S. (2003). "Yttrium zoning in garnet: Coupling of major and accessory phases during metamorphic reactions." American Mineralogist 88(4): 708.

Råheim, A. (1977). "Petrology of the Strathgordon Area, Western Tasmania: Si4+-Content of Fengite Mica as Monitor of Metamorphic Grade." Journal of the Geological Society of Australia 25: 329-338.

Råheim, A. and Green, D. H. (1974). "Talc-Garnet-Kaynite-Quartz Schist from and Eclogite-Bearing Terrane, Western Tasmania." Contributions to mineralogy and petrology 43: 223-231.

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Reed, A. R., Calver, C. and Bottrill, R. S. (2002). "Palaeozoic suturing of eastern and western Tasmania in the west Tamar region: implications for the tectonic evolution of southeast Australia." Australian Journal of Earth Sciences 49(5): 809-830.

Robyr, M., Vonlanthen, P., Baumgartner, L. P. and Grobety, B. (2007). "Growth mechanism of snowball garnets from the Lukmanier Pass area (Central Alps, Switzerland): A combined ?CT/EPMA/EBSD study." Terra Nova 19(4): 240-244.

Schwartz, J. J., Gromet, L. P. and Miro, R. (2008). "Timing and duration of the calc-alkaline arc of the pampean orogeny: Implications for the late neoproterozoic to cambrian evolution of Western Gondwana." Journal of Geology 116(1): 39-61.

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Monday 19 January 2009

Hey, I’m an international expert!

For the first time today I received a random e-mail from a stranger asking for help with a geologic question. I happened to check my hotmail address (for the first time in at least a month), and saw a very short note from a researcher in India, who asked me to assist him with creating “pseudosections” for his samples using THERMOCALC, and he attached a file of his data. I opted not to open the attachment, but instead sent a politely worded note letting him know that I don’t actually know how to use THERMOCALC, but that I had been taught to use PERPLE_X, which gives similar results (and added a citation to a paper which used both programs to compare them). I added that for prompt replies, he’d be better off using my uni e-mail address, as I only check the hotmail account about once a month. I did not provide said address, but it is available in a few places on line if you know my name.

Much to my surprise about a half an hour later there was a longer note from him in my uni in-box, explaining that he’d tried using PERPLE_X, but had encountered problems with a specific step in the process, and could I please help him create pseudosections; one of his papers was being held up in the review process because he hadn’t created a pseudosection for his data, and that he’d be happy to give me full credit for the assistance—but if I couldn’t, could I perhaps send him my build file so that he could figure out how to edit his so that it would work.

I happen to have a Word document which I call upon any time I need to use the “build” program in the PERPLE_X suite of programs, wherein I have all of the questions the program asks in black, and the answers I give it in blue. Any time I need to run a new sample, I edit that document first to contain the data for the new sample, and then run build and copy-paste the answers into the program. Therefore it was the work of perhaps three minutes to reply to his e-mail with a copy of that document and suggestions of how to use it and what to do afterwards, along with an apology stating that I wasn’t able to do the work for him, as I really need to finish the writing of my PhD, which is behind schedule. Aren’t they all?) This got me a very polite letter of thanks. I hope he is able to make the program work.

Somehow, being seen as enough of an “expert” in my field to get random letters from strangers asking for help with their own research feels pretty good. It has been an intense 3 ½ years working on this project, but the end is in sight, and I can tell from here that completing the degree isn’t really the end, but rather is just the very beginning. There is ever so much more that I can learn, to build upon the knowledge I have gained here. I am starting to see post-doc positions advertised in my areas of speciality, and am applying for them. Each one has its own appeal, and would draw upon different strengths and use different skills. I can’t yet tell where my path will take me next, but the glimpses I’m starting to see through the trees are very, very intriguing.

Thursday 15 January 2009

Always double check!

I collected most of my samples for my PhD project in March of 2006, consequently their field numbers start 06___. Those samples all came from the northern fault block of the Collingwood River Metamorphic Complex. In November of 2007 my advisor and I did one additional trip, to the southern fault block of the Collingwood River, in search of the long-lost Tasmanian whiteschist. We found it, and collected a number of other samples from the area as well. Whilst we were out, we also stopped by the northern block and picked up another couple of oriented samples, just for good measure.

In October of 2008 we decided that there was just enough funding left to do some detrital zircon dating for two samples from the Collingwood River. I was told to select "sandy" samples as being most likely to contain zircons. So I picked out half a dozen from both the northern and southern blocks of the Collingwood River which were sandier than the others, though not necessarily sandy enough, and brought them along to my lesson on rock crushing. My teacher du jour narrowed it down to three likely candidates, two with 06___ numbers, and one with a 07___ number. So we, thinking that there might be value in having one from each fault block, chose one of each and we commenced crushing.

Since then I've been thinking in terms of having crushed one from each fault block, so was not too surprised when their detrital zircon patterns were somewhat different from one another. Today, at long last, I decided to make the figure showing the location these two samples were collected from. Yup, you guessed it. They are both from the north block! They were collected from locations not more than 250 meters apart from one another along the highway.

However, since the other 07___ samples were all rejected as not being sandy enough to bother, I can't really complain that I don't have one from each block. There is just that lingering embarrassment that one gets when one realizes that the assumption under which one has been operating doesn’t actually apply. The best cure for that? Admit the mistake publicly—then it won’t ever be repeated!

And always consult the map...

Wednesday 14 January 2009

Why is it harder?

A friend of mine, who is working on her PhD in Medieval Literature, recently wondered in my hearing why it is that the dissertation (or, here in Australia, the PhD thesis) is so much more difficult to write than any other paper, ever. I couldn’t help agreeing with her on that observation, although I’m not certain I am able to give a complete answer to the question. One major factor may well be the time scale in which the project is undertaken. A paper which is written over the course of a month or two will be easier to keep coherent—to use a consistent voice throughout, and to make certain that all lose threads are tied up before the conclusion of the discussion. A PhD project on the other hand, takes years to complete. Research which is done early on is either written up straight away, or it is set aside and we have to go back to old notes from (by now largely forgotten) previous works sessions and write it up. While it makes much sense to do the writing as the work is done, for a PhD project with a steep learning curve (aren’t they all?), it is very likely that things learned over the course of the project will mean that what was written for segments done early on will need to be changed, often dramatically, for the final write up. On the other hand, if one chooses *not* to write paragraphs about the work done early on, but to simply leave the data & graphs to stand on their own for writing at a later date then much time is wasted looking over the data again, trying to remember what was done with this sample before the writing can commence.

In my case the writing bits of it here and bits of it there have conspired to add an additional complication. I’ve just received back comments from my advisor on one of my chapters, and he points out that the thesis is meant to be written in a formal style throughout, yet in some places I’ve adopted a casual, chatty tone summarizing what I did to obtain the results. Looking over my work I see that he is correct, the voice used varies greatly from one segment to another, no doubt based upon how I was feeling on any given day, how much sleep I’d had, if I was hungry, and, possibly, even what the weather was like on the day. So not only do I need to finish up the summary of all of my results, I also need to read over everything and convert it all to a consistent writing style. Why didn’t I think about that aspect earlier along in the writing process?