COG3 Seminar: Julie Huber (WHOI)
Friday, April 27, 2018 at 10:00am to 11:00am
Building E25, 119
45 CARLETON ST, Cambridge, MA 02142
"Subseafloor life in the cold, oxic crustal aquifer”
The cold, basalt-hosted, oceanic crustal aquifer is one of the largest ecosystems on Earth, yet little is known about its indigenous microorganisms and their impact on biogeochemical cycling. Subseafloor observatories on the western flank of the Mid-Atlantic Ridge penetrate hundreds of meters into the crust and provide an unprecedented opportunity to investigate microbial life in this understudied realm. Here, the first evidence for an active microbial community in fluids that circulate through the crustal aquifer beneath North Pond, a ~200-m-thick sediment-filled basin overlying relatively young basaltic crust (8 Ma) will be presented. Geochemical and microbial data from multiple depth horizons of the subseafloor observatory will be presented, including stable isotope incubations, metagenomics, and organic carbon dating and fingerprinting. Results indicate that while crustal fluids from North Pond are highly similar to deep Atlantic bottom seawater, a distinct and dynamic microbial community exists beneath the seafloor with the capacity for both autotrophy and heterotrophy. The cool, oxic subseafloor community at North Pond maintains distinct microbial communities from deep seawater and plays an important role in the degradation of aged organic matter in the deep ocean.
About the Speaker
Julie is an oceanographer by training and is broadly interested in how basic earth processes- rocks forming, fluids moving, sediments accumulating- interact to create and maintain life in the oceans. Her research addresses some of the most central questions about the nature and extent of life on Earth in one of its least explored corners, the subseafloor habitat beneath the ocean floor. She investigates subseafloor microbial communities to resolve the extent, function, evolutionary dynamics, and biogeochemical implications of this relatively unexplored ecosystem. The questions her work addresses are universal for understanding the impact of microbial life on both human and planetary health and the selective forces that continue to allow life to establish, thrive, and diversify on Earth.
About this Seminar
The Chemical Oceanography, Geology, Geochemistry, and Geobiology Seminar [COG3] is a student-run seminar series. Topics include chemical oceanography, geology, geochemistry, and geobiology. The seminars take place on Fridays from 10-11am in Building E25, Room 119, unless otherwise noted (term-time only).