On the first day we went out to the Black Rock Desert and looked at some basaltic volcanics. Most of the day was spent driving around in the middle of nowhere (actually we were right in the middle of where the big fires were this past summer). At the end of the day we stopped at an outcrop of obsidian. Obsidian is found at the basal vitrophere of a lava flow where it cools very quickly. We learned that the white snowflake looking things are made when the obsidian starts to devitriphy (change
from a glassy texture to a crystaline one) around a quartz or feldspathic particle. 
The Pavant lava flow takes up a large part of the Black Rock Desert. The vent area for this flow is the Pavant Butte. It's basaltic in composition but is given it's lighter color vo the calcite that holds it together. The westward side of this cinder cone faced Lake Bonneville, causing it to be a wave cut cliff. The strange, drooping, face of the cliff was formed by differential erosion.
Wednesday we spent a lot of time working with the Price River and North Horn Conglomerates. Most of our time was spent in the Spanish Fork Canyon area. We climbed a lot of talus (I don't like climbing up it either, Gerb).
Thursday I got to see some very nice gneiss and schist. If you ever want some good metamorphic rocks to add to your rock collection, there's a wonderful canyon east of Santaquin that is just full of beautifully banded gneiss and schist with some of the best schistosity I've ever seen. This particular pieces of gneiss has some huge crystals of potassium feldspar and quartz. We also did a lot of mapping up in the Little and Big Cottonwood Canyons. I can't say that was my favorite part, but I did learn a lot. It's amazing how nerdy a bunch of geology students can be. We get so excited when we start hammering away at our rocks, identify the minerals in them, and find great handsamples to bring home. I'll never look at a rock the same again...
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