Day 5 - The Grander Canyon

We’ve been here 5 days now, and everyone who was overly excited to make rock puns already volunteered for blog entries, so adjust your expectations accordingly.  We started off the frigid Monte Negro morning with breakfast and proceeded to pack the cars. Then we embarked on the journey of a lifetime, complete with sketchy dirt roads, confused cows in the way, and great driving tunes.

We started off our day’s excursion by hiking about 15 minutes to our first outcrop where we were able to view a huge cliff off in the distance on one side and a waterfall on the other.  We could tell by the vertical jointing displayed by the outcrop that it was similar to the basalt one we studied yesterday allowing us to identify it as an igneous rock formation. After our distant observations of the outcrop, we marched over the river and through the woods — and over some tetanus-infused barbed wire — to more closely observe the outcrop. Up close, Guil and Lydia elaborated that there are often things that we cannot determine simply by observing a rock, but rather we need to take samples back to the lab and observe them under a microscope. While our intuitions led us to believe that the rock was a basaltic lava flow, we learned that this outcrop was actually rhyolite — a silicic igneous rock with a high viscosity.

During our conversation about the rocks, clouds approached us through the canyon and slowly engulfed us, cutting our visibility but making for some pretty cool silhouette pictures.  Our lunch today was packed by the Pousada Fazenda Monte Negro, the Brazilian Dude Ranch we’re staying on, and the sausage and cheese sandwiches almost made for a nice change from the ham and cheese sandwiches we’ve had the past five days.

Today also marked our first mini-lesson in ecology, with yogi Jen taking the lead in explaining how the deforestation around the canyon is due to cattle-ranching. Today marks a monumental moment in our Maymester, as we were finally able to sketch something other than rocks — plants. Following these sketches, the groups split in two with one group proceeding to another outcrop and waterfall, while the other group proceeded back to the cars to regroup, and of course picked up another stray dog along the day.

Finally, the separate camps reunited to observe our ultimate outcrop. Here, we found yet another igneous rock formation, similar to the initial cliff we studied but weren’t fortunate enough to rappel down.  However, by observing the similarities in the features between the two outcrops we were able to interpolate that, upon closer observation, the vertical jointing was in fact columnar jointing caused by the pathways of heat loss in the magma.

To wrap up our eventful day we moseyed our way back to our cabins for some ice cold showers and pre-dinner naps in preparation for a much-needed Brazilian feast.

Sugar, Spice, and Everything Nice,

Grant 1 and Grant 2