I find that I’m liking this “active reading” stuff. It used to be that on days like yesterday, when I didn’t get around to reading my 1000 words of geologic literature till very late in the day I’d “read” it, as in my eyes would look at each word on the page, but it was more along the lines of “skimming” it, and it is somewhat doubtful how much, if any, was actually retained. Yesterday, however, I actually got meaning out of each and every paragraph I read. I know this, because it isn’t possible for me to type a sentence or three about what it says if I don’t understand it first.
Normally I’m a two-monitor kind of person. If I need to read something and type notes about it, I keep the article on one screen, and the word-processor on the other. Yesterday, on the other hand, that wasn’t possible. I’d spent the day using the electron microprobe and when it was time for the ‘probe’ operator to head home for the day I was tired, so I simply took my computer home with me, rather than bringing it back up the stairs to my office. As a result when I realized hours later that I still needed to do my 1000 for the day (I’m at 82 days in a row now this time!) I was faced with the choice of dealing without a second monitor or carrying the computer back to my office.
The solution I hit upon worked very well—I’d copy-paste a single paragraph into the document in which I was working, read it, type up my summary, then move that paragraph into an otherwise empty document. At each minor section break I’d do a word-count of the document which contained only the paragraphs I’d already read, to see if I’d done 1000 yet. As it turns out, I hit 1053 words at one of the minor section breaks, to the notes below don’t end in quite as logical of a place as the previous batch, but I was tired (Europe only just did the change to daylight savings this weekend), so called it good. It is interesting to note that my summary, including the headings “Paragraph 1, 2, etc.” took 581 words to summarize the 1053 words of the original.
When first I started reading 1000 words a day I thought of it as a 20-minute time commitment. Reading this 1053 words and typing up a summary took 54 minutes. Therefore it takes nearly three times as many minutes, but I think that the gain is more than four-fold the amount of information retained.
Here follows the summary in progress for the article Metamorphism and deformation at different structural levels in a strike-slip fault zone, Ross Lake fault, North Cascades, USA by Gordon et al 2010:
Paragraph 18 informs us that it can be difficult to find appropriate mineral assemblages for P-T estimates in the Skagit Gneiss. They mention a previous study which used 4 metapelites, and tell us that this study found 4 useful metapelites and three garnet amphibolites between the Skagit Gneiss and the Napeequa unit.
The next section focuses on the garnet amphibolites
Paragraph 19 specifies the locations for the three garnet amphibolites that yielded PT estimates and gives the units thereof.
Paragraph 20 mentions which two amphibolites (from Ruby Mt.) are migmatic adn which one isn’t (from Elijah Ridge) and gives the mineral assemblages and fabric.
Paragraph 21 describes the garnet in one of the amphibolites, giving size, general composition, mentions that it isn’t zoned (and states that this is normal for the unit), list of inclusions, and the fact that some of them display post-kinematic coronas.
Paragraph 22 describes the garnet from one of the two other samples in the other unit, mentioning their size (smaller than last paragraph), and the fact that minor growth zoning is present, and points out that the final sample is very similar to this one.
Paragraph 23 describes the hornblende of all three samples, two of which have zoning (just like the garnet from the same unit), but zoning is rare in the other sample (just like the garnet from that sample)
Paragraph 24 mentions the zoning of the plagioclase in all three samples, states that for the Ruby amphibolites the reverse (An increase to rim) zoning is more common & more variable than the normal (An decrease to rim) zoning that is present.
Paragraph 25 describes the plagioclase zoning for the Elijah ridge amphibolite, which also has more reverse than normally zoned examples. However, in this case the normal zoning is more variable than is the reverse.
Paragraph 26 mentions which sample contains clinopyroxene, and the fact that it isn’t zoned and is both in the matrix and as inclusions within the garnet.
Here ends the section on the minerals present in the amphibolites. The next section looks at the metapelites.
Paragraph 27 lists the locations (2 from Ruby Mt, and 2 from Elijah Ridge) and general assemblages of the four metapelites used in this study, and specifies which ones are structurally higher than their neighbors, and which pair is structurally higher than the other.
The next section focuses on the Ruby Mt. Metapelites.
Paragraph 28 lists the major (grt-bt-sil-ky-crd-qtz-pl) and accessory (il-zr-apt-mnz) minerals present in these rocks and point out that the sillimanite one has pseudomorphic textures hinting at former kyanite while the kyanite bearing one has some sillimanite. It also specifies the habits of the cordierite
Paragraph 29 describes the fabrics present, and where possible mentions what that says about the T at which each deformation happened.
Paragraph 30 describes the habits of garnet in one of the samples (including what is included therein) and cordierite and points out evidence for a retrograde reaction of grt-crd.
Paragraph 31 continues with the same sample as last paragraph,stating that plagioclase isn’t generally zoned, the biotite is homogeneous, and describes alignment of sillimanite with the foliation. It also reminds us that kyanite used to be stable in this sample.
Paragraph 32 moves on to the other sample, lists minerals present, compares garnet, plag, and biotite with last sample, describes the kyanite and sillimanite present.
There ends the description of the minerals in the metapelites from Ruby Mountain. The next section will describe those from Elijah Ridge.
Tales from the Summer Break (3)
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