Ammonite

Ammonite

Wednesday, May 9, 2012

Assembling California


This months selection for book club was Assembling California by John McPhee. You may recall that he also wrote Basin and Range. I think he is a really great writer, and despite the book being somewhat outdated, it is pretty good. Any volume on geology that can contain the words pluton, xenolith, and ophiolite, and still be interesting to the average reader is truly a treasure. Trust me I know;) McPhee mixes it up by talking a little geology, and then inserting a slightly irrelevant, but none-the-less interesting topic like the names of mining towns, or a childhood history, before going back to the geology at hand.
I also appreciate the way he chose only a few aspects of California's geologic history to focus on, letting others pass unexplained. There is just too much to say about the geology here to write an inclusive book intended for the general populace. So I am glad he didn't try. It would have ended up confusing and uninteresting. I believe his strategy was similar to the one I had for the lab classes I taught. I kept it simple, picked things that were a.) exciting, b.) not to difficult to understand, and 3.) inspiring.
The book is organized so the reader accompanies McPhee from eastern California (at the latitude of Lake Tahoe along Interstate 80) to the western coast. As he hops from outcrop to out crop, road cut to road cut, he jumps back and forth in time as well. He might be inspecting an ophiolite sequence in the present, then switch to describing it as it would have been millions of years ago, and miles from it's present location. Then he moves back up in time, but not quite to the modern day, and tells a story about an old 49er (in 1849) named Jim-Bob who had a placer mine just down the slope. In that way he weaves geologic time with historical time, and manages to tell a pretty good story.
Reading on a bench outside the library.
It's also a pretty great historical text because most of the people he interviewed for his book (and much of the commentary) revolve around the "newly" accepted theory of plate tectonics. I sometimes forget that it was only in the 1960's that plate tectonics theory was developed. Up until then geology had been stuck in a rut with several unsatisfying hypotheses for the formation of mountains and the like. As McPhee points out, there are marine fossils on the top of Mount Everest, the highest mountain in the world. For a long time no one could explain how they got there. Plate tectonics changed all that.
I also thought it was interesting to learn that the origin of the state was from a story written in the 1500's by a Spaniard, about an island called California (after their Queen Califia) full of black amazon women with gold weapons and armor, who ate men and male babies and flew on griffins;)  I think it's at least partly fitting since California is a collection of island arcs accreted onto the western coast of North America, and because there is so much gold here. I tried to find a copy of the story, but to no avail. The best I could get was the summary from wikipedia. It's an interesting read though.
Anyway, it was an excellent book, and I highly recommend it to anyone interested in the geology of California, geology in general, or the mining towns in the western foothills of the Sierra.

No comments:

Post a Comment