Collaborative Research: Drivers and Dynamics of Methane Seepage Along the US Atlantic Margin

Methane plays an important role in controlling climate on earth. Recently it has been found that methane is seeping from the seafloor into the Atlantic Ocean along the Eastern United States. Methane seeps like these may be common along similar coastlines and thus may affect our climate. The reasons for these methane seeps will be studied using geological, chemical, and biological methods. The project supports students at various levels and contributes to public understanding of the ocean through talks, publications, and videos. Summer camps designed to inspire the next generation of ocean scientists will be developed. The field work and community outreach will improve our understanding of methane's role in climate and contribute to public understanding of and appreciation for ocean science. This project will study biogeochemical and geological controls on recently discovered methane seeps in the northern US Atlantic Margin (200-1000m depth). Existing conceptual models of the origin, subsurface migration, characteristics, and history of methane discharge along continental margins would not predict the widespread presence and depth distribution of these seeps. This work will integrate geochemical, microbiological, geophysical, and geological data to investigate the genesis of seep fluids, fluid migration, and methane oxidation processes in a modern seep while reconstructing methane seepage characteristics and gas hydrate stability in the past. The project will combine geophysical characterization with the autonomous underwater vehicle Sentry at active seep sites. This will be combined with gravity and jumbo piston coring from ships as well as targeted sampling using the human occupied deep submergence vehicle ALVIN. This strategy will retrieve multiscale seafloor and sub-seafloor datasets, capturing a record longer than previously recovered at any other seep along this margin. The multi-pronged approach will contribute to an integrated and mechanistic understanding of continental margin methane seeps. This project is jointly funded by the Directorate for Geoscience’s Chemical Oceanography and Marine Geology and Geophysics programs and by the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.