Prof. Dr. Andreas Teske
Projects & Publications
Fossil carbon, including petroleum and gas, drives entire microbial ecosystems that rely on these unusual carbon sources, including the powerful greenhouse gas methane, and that in turn shape the natural cycles of carbon and biomass that is influencing Earth’s climate. Studying the microbial cycling of fossil carbon in its original subsurface context requires an oil- and gas-rich field site where microorganisms thrive at hot temperatures, the hydrothermally active Guaymas Basin in the Gulf of California (Mexico). Whereas my previous expeditions to Guaymas Basin sampled hot hydrothermal vents at the seafloor, my 2019 deep-drilling expedition probed deep sediments and volcanic rocks to 500 meters below the seafloor, towards extremely hot conditions where microbial life becomes extinct and chemical processes take over. Subsequently, I have coordinated hydrothermal and deep biosphere studies on Guaymas Basin with my Hansekolleg partners and several international collaborators. Although the pandemic delayed some projects, we have learned how different kinds of microorganisms are distributed in the subsurface, how they react to increasing temperatures, and how organic matter is transformed by microbes and by non-microbial factors in the Guaymas subsurface. Now is the time to focus on specific connections between subsurface microbes and their environment, and to zoom in on the critical boundaries between biological and non-biological processes that are poorly known.