The Bighorn Basin Coring Project

From mid-July to the beginning of August, I’m going to be outdoors, in Wyoming. No, I’m not crazy. Yes, I have a good reason for doing this. Because in the summer, that’s when we’ll be coring through the Willwood Formation in the Bighorn Basin. And this is a big deal.

The Willwood Formation is about Eocene in age, and sits on top of the Paleocene Fort Union Formation. The Willwood Formation is mostly a lot of paleosols (lithified soils) and river sandstones. And more importantly, the sediments that form these rocks were laid down during the Paleocene-Eocene Thermal Maximum, and then the later, smaller thermal maximums during the Eocene. As a quick summary, taken from a thesis proposal I’ve been using in order to beg for money1:

The sedimentary geologic record can be used as a window into the past conditions of the Earth, including the climate in which sediments were laid down. In the Cenozoic, there are many examples of shifts in global climate. Potentially significant to the modern climate in which humans live are the hyperthermal events that occurred during the Eocene. Hyperthermals are relatively brief (~100,000 years) warming events that coincide with the release of massive amounts of carbon from terrestrial reservoirs. The most well understood of these hyperthermals is the Paleocene-Eocene Thermal Maximum (PETM), which occurred 55.5 million years ago. During the PETM, 6,800 Gt of carbon were added to the shared carbon pool of the atmosphere and ocean, and global temperatures rose 5-9° C (Sluijs et al. 2006, Zachos et al. 2008). Slightly more recently (53.7 Ma), the Eocene Thermal Maximum 2 (ETM2, also called ELMO) occurred. ETM2 is about half the size of the PETM isotope excursion (Lourens et al. 2005), and generally much less well understood.

This project is a big deal, for several reasons. Just to start, coring is not a cheap process, and this project is funded by a pretty major grant from the NSF. But what’s more important is what we hope to learn from the cores. The PETM is of great interest to climate scientists and geologists right now, because it’s perhaps our best historic example of what humans are currently doing to the planet. There weren’t a bunch of little proto-horses in the Eocene burning oil so they could roar around in ridiculous cars, but it was a sudden, rapid surge of carbon being put in to the atmosphere, even if the source is being debated.

This is important because, no matter how many people2 in the world are short-sighted and basically sticking their fingers in their ears and shouting “Lalala can’t hear you” every time someone brings up this science, that doesn’t make it any less real and pressing.

The paleosols, which are what I’m mostly interested in, can tell us a lot about how the local climate shifted in response to the PETM. This is important, since most human beings have a vested interest in their local environment not suddenly changing and, say, making it impossible for them to grow food. Also, one of the cores will be through the ELMO thermal maximum, which I think will end up providing a valuable set of comparative data. There’s already some pretty robust data for the PETM in the Bighorn Basin, and the cores will give us even more. If we then compare that data to what we come up with from ELMO, that may give us a sense of just how far a local environment will shift pushed by how much carbon – because it may not need an input as big as that in the PETM to really mess things up.

Hopefully, that’s enough to get you interested! The BBCP has a facebook page now, here. When we’re actually coring during the summer, there will be a blog for the project hosted by Smithsonian, which I’ll link to when it’s up. I’ll also no doubt be blogging about it here, and I think I’m going to be responsible for tweeting about it as well.

The coring is going to run from July 13 through August 8. I’ll probably be on the rig from July 19 through the end of the project, since I’m going to try to go to TAM before I head up to Wyoming. I’ll also be on the night shift the whole time – coring is a 24/7 process – so I guess I’ll be documenting BBCP – After Dark3.

Once we’ve got our cores, we’ll actually be sending them out of the country (since this is a project with multinational investigators!) to Bremen, Germany. They’ll be living at the Marum core repository, which is also where all of the Integrated Ocean Drilling Program cores go. That means in January 2012 (if I can find the funding for it!) I’ll be heading off to Bremen for three weeks of intensive core prep, description, and sampling.

And then, science! Lots of science!

Year two of grad school is looking ridiculously exciting.

1 – It’s a time-honored scientific endeavor. I wish I was joking when I say that.

2 – Here, I use the term people in place of the perhaps more true but less polite term: idiots.

3 – I actually volunteered for this. If you knew how badly I sunburn, you would understand why. I also don’t like the heat, and it’ll be much cooler at night.

References
Lourens, L. J., Sluijs, A., Kroon, D., Zachos, J. C., Thomas, E., Rohl, U., Bowles, J., and Raffi, I. 2005. Astronomical pacing of late Palaeocene to early Eocene global warming events. Nature, vol. 435, p. 1083-1087.

Sluijs, A., Schouten, S., Pagani, M., Woltering, M., Brinkhuis, H., Sinninghe Damsté, J. S., Dickens, G. R., Huber, M., Reichart, G.-J., Stein, R., Matthiessen, J., Lourens, L. J., Pedentchouk, N., Backman, J., Moran, K., and and the Expedition 302 Scientists. 2006. Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum. Nature, vol. 441, p. 610-613.

Zachos, J. C., Dickens, G. R., and Zeebe, R. E. 2008. An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics. Nature, vol. 451, p. 279-283.

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