The Rocky Mountains and a big blue Montana sky provided the backdrop for the Deep Carbon Observatory summer school this month. Thirty PhD students and postdocs from across the globe came to learn about carbon cycling at Yellowstone National Park. Organised by Adrian Jones (University College London) and John Baross (University of Washington), this summer school brought together early career researchers from all four DCO communities, from Deep Life to Deep Energy. The supervolcano and associated hot springs at Yellowstone were the perfect natural laboratory within which to explore the different processes active within the Earth. The huge volcanic caldera here throws out enormous volumes of carbon dioxide, while the multitude of colourful hot springs provide a glimpse into geothermally-driven microbial ecosystems that are similar to those that once existed billions of years ago on the early Earth.
Over five days, we were taken through the geology, geochemistry, and biology of Yellowstone, which included going into the park itself (clearly the two best days of the week!). Our incredible guides were Lisa Morgan, Pat Shanks, and Bill Inskeep from the United States Geological Survey and Montana State University. If being taught by the very people who literally wrote the book on Yellowstone wasn’t great enough, we also got to hear some incredible fieldwork stories about bears, pyroclastic flows, and watching the Mt St. Helens eruption unfold from the seat of a light aircraft above.
For me, the multitude of hot springs here were the #1 highlight of the week. From boiling acid and alkaline pools to gloopy mud pots, the whole area is a total microbial wonderland that capitalises on all the sulfur, carbon dioxide, and hydrogen spewing out of the ground. The #2 highlight was seeing BEARS! While driving along, we were lucky enough to chance upon a black bear family – a mum and two cubs messing about by a river. During our week here we also saw big stocky bison roaming the meadows, a bald eagle, elk, and cute little chipmunks.
Day two at the park ended in a long but worthwhile diversion to see Mammoth Hot Springs. Mammoth is made up of beautiful, bright white mineral terraces formed out of carbonate, which precipitates out of the carbon-dioxide rich fluids that emerge here. As with Grand Prismatic Spring above, the coloured streaks on the surface are caused by photosynthetic microbes, which use these bright pigments to absorb sunlight.
The main focus of this week was understanding how major processes such as caldera-forming eruptions and microbial evolution are linked across space and time. The type of volcanism here (mostly rhyolitic) dictates the geochemistry of the geothermal fluids that circulate through the rocks, which in turn affects what particular bacteria and archaea are able to colonise the hot springs (different geochemistry = different things to eat). Through this connected system, geologists and biologists find common ground (the geochemists lurk somewhere in the middle) and provide the basis for establishing cross-disciplinary links, something which is becoming more and more essential in order to understand the world we live in. All in all, it was a great week that went too fast, with great science and great people. The only downside? Being charged $12 for a scotch one night (as someone who lives in Edinburgh, this was very painful).