We spent the 14th through the 17th working on rocks from the Denver basin; two small outcrop sections and one session of sampling from a core they drilled through the basin a few years back. The outcrops were out near a ranch on the plains east of the Front Range. Bijou creek cuts an escarpment down into the landscape, so as you look out across the area, you can barely tell any topography exists, but as you get closer to the edge, near the house on the ranch, the ground falls away in front of you revealing a funny escarpment exposing a 10 meter thick paleosol and a pretty little slot canyon through Paleocene-aged rocks (~65 to 55 million years ago) and down into the Cretaceous-Tertiary boundary (aka the KT boundary @ 65 Millions years ago). For those of you who don't remember this point in earth history, the KT boundary marks a large meteorite impact and the death of the dinosaurs.
So, it was a change of pace, as we were focused on a single, thin outcrop, so we dug a big trench through the escarpment in a couple of places and took samples. All the while, it was castration time on the ranch, so every few minutes while we were digging we'd hear the most anguishing cries from off in the distance. Either that, or it was the cries of love-sick cows, as they moved one of the bulls during lunch time.
We took our first day off of the trip after two days on the escarpment, when some of our collaborators were at work on some unrelated sections. On the 17th, we headed to the giant Denver Federal Center, to work on the preserved core that is stored at the US Geological Survey, in a warehouse that looks remarkably like the scene from one of the Indiana Jones movies .
Now, if you thought sampling pits made boring photos, core shots are even worse.
But, sampling is a lot faster when you don't have to dig a pit, and we got to take a tour of the National Ice Core Laboratory (basically in the same building), which is where they store and study the ice cores from Antarctica and Greenland. Ice cores are extremely useful for paleoclimate studies; the gas bubbles trapped in the ice record past atmospheric CO2 concentrations, oxygen isotopes in the gas are used to get at past temperatures, and you can date them pretty well by counting the layers.
The only problem is that the record currently only covers the last 800,000 years. So, we walked through the freezers, some dressed more warmly than others,
into temperatures around -30 fahrenheit (eyelash and booger-freezing temps, if that helps). It was good, because we enjoyed the 100 degree temperatures outside for a good 10 minutes after that!
We also enjoyed a free trip through the Denver Museum of Nature and Science, and saw the big Titanic exhibit (according to our entrance tickets, Tracy and I were both first class male passengers that survived the sinking), and a great IMAX film about the role the bayou wetlands play as a hurricane barrier and how their disappearance played a major role in the massive damage Katrina inflicted on New Orleans. Great music too.
