The first outcrop Guil brought us to was Blood Outcrop - affectionately named so after Guil once lost a fight with its rocks. We climbed through tall, thick grasses only to find - you guessed it - more pancakes. Then it was #1 TA Lydia vs. Rock, as she graciously tried to break off samples for us to look at and take back to their lab. Fortunately, Lydia won, and we used those samples to learn about how the outcrop formed. Around 135 million years ago, an explosive eruption created these deposits of igneous rocks and Barbosas (the pancakes) for us to admire and Guil to shed blood on. Barbosas are explosive blobs that are deposited when volcanoes erupt. They are more cohesive magma blobs that are not blown apart during eruption (unlike the torn apart matrix around them). They become progressively squished as you look down the outcrop due to compression forces. Barbosas are certainly a favorite of our group.
Fast forward to Newgene's death at the next outcrop and the biggest showdown the Maymester has seen since the Sand Dunes Incident of 2016. With our backs to a gas station, we were faced with the swirliest outcrop so far. The rift in the group started with Guil and Lydia's metaphorical descriptions of the outcrop. Did it look like toothpaste, as Guil suggested, or like pudding, as Lydia explained? After a quick lunch break and an hour of difficult sketching, we launched into our debate. It was Team Guil vs. Team Lydia. Team Guil believed in the Barbosas. This was an explosive outcrop, highly deformed post-deposition. Team Lydia, on the other hand, liked to think Team Guil had been fantasizing about pancakes for far too long. Team Lydia took a more effusive route, thinking that this was a part of a dome structure. After literally hours of debating, much frustration, and an officially pronounced dead Newgene, we headed off to our next outcrop.
A couple hours later at sundown, while leading our convoy down the mountain, Guil veered off the road for one last stop. Naturally, within five minutes of us crawling out of the vans, it began to rain. While this led to a slight drop in group morale, Guil assured us that nothing could stop geology from happening. To Ali and Jen's dismay, the group was led by Guil (safely) down the side of the highway. There we met two types of rocks - obsidian and rhyolite. Guil asked us which rock was deposited first, almost beginning a new Great Debate. Fortunately, Sam saved the day by shouting out the wrong answer immediately, causing Guil to give us the less-than-obvious hint that the rhyolite did in fact come first. Turns out, we were looking at an obsidian dome that intruded into the rhyolite, as evidenced by the rhyolite inclusions within the obsidian. Satisfied with finally getting a straightforward answer, we headed back to the cars to continue on our way to Torres.
We were not greeted with an outcrop in Torres, but instead our friend Pablo with Newgene 2.0! Hopefully Newgene 2.0 can survive Guil's crazy road trips for the next couple of days.
Rock on,
Sam & Ali
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