Award: OCE-1357360

Intellectual Merit: The Gulf of California is an active, young ocean that is undergoing early phases of rifting and seafloor spreading. Active hydrothermalism generates oil and the hot fluids that discharge from the seabed are enriched in energy rich substrates, like methane, ammonium, hydrogen sulfide, carbon monoxide and reduced metals, that are utilized as energy substrates for microbial communities. The geological setting in Guaymas Basin creates a diverse range of biogeochemical habitats that are exploited by diverse microbial populations. These areas provide a natural laboratory to study how seafloor processes shape the evolution, physiology, and activities of microbial communities that mediate key geochemical reactions. Our work revealed the pathways and dynamics of key processes – four different types of methanogenesis and the anaerobic oxidation of methane – that produce and consume methane, respectively, in sediments. Methane is a potent greenhouse gas so it is important to understand the factors that regulate its production and flux in the environment. Our findings advance the understanding of how environmental factors regulate the critical microbial processes that moderate methane fluxes in natural habitats. Broader Impacts: This project contributed to the training and professional development of six graduate students, two postdoctoral scientists, and one research professional. The young scientists involved in this program participated in highly interdisciplinary sea-going research expeditions utilizing human-occupied submersibles (the ALVIN), remotely operated vehicles, and the mapping autonomous vehicle SENTRY. At sea, these young scientists contributed to day-to-day vehicle operations and CTD sampling and learned to work seamlessly with a large science team. This program contributed significantly to public outreach and education. In addition to a project webpage and blogs from our research expeditions, we worked with cartoonist Jim Toomey to develop a cartoon "The Adventures of Zack and Molly: The Amazing Beggiatoa", describing some aspects of our work in Guaymas Basin. Finally, artist Rebecca Rutstein joined our 2018 expedition and generated a number of incredible paintings and sculptures for exhibition in the Georgia Museum of Art. While at sea, scientists and members of the ships crew and the Alvin and Sentry crews interacted with Rebecca and influenced her work. To date, over 70,000 people have viewed the sculptures and paintings on display at the Georgia Museum of Art in Athens Georgia. Last Modified: 05/24/2020 Submitted by: Samantha B Joye