Geologic methane seeps in Arctic Alaska

Katey Marion Walter Anthony, University of Alaska, Fairbanks, kmwalteranthony@alaska.edu (Presenter)
Janelle Sharp, University of Alaska Fairbanks, janelle.sharp@nana.com (Presenter)
Melanie Engram, University of Alaska, Fairbanks, melanie.engram@alaska.edu
Prajna Regmi Lindgren, University of Alaska, Fairbanks, pregmi@alaska.edu
Peter Anthony, University of Alaska Fairbanks, pmanthony@alaska.edu
Franz Josef Meyer, University of Alaska, Fairbanks, fjmeyer@alaska.edu

Methane (CH4), a potent greenhouse gas, accumulates in subsurface hydrocarbon reservoirs. In the Arctic, impermeable icy permafrost is thought to form a ‘cryosphere cap’ that traps gas leaking from these reservoirs, restricting flow to the atmosphere. We document the release of geologic methane to the atmosphere from large gas seeps in arctic Alaskan lakes using remote sensing and field work. While some seeps occur along boundaries of thawing permafrost (e.g. near large rivers with presumably through-going taliks and along the continuous-discontinuous permafrost border), others occur in inland lakes where continuous permafrost thickness likely exceeds talik depths beneath lakes. This raises questions about gas migration and release mechanisms in the continuous permafrost zone.

Associated Project(s): 

• Meyer-01
• Miller-C-05

Poster Location ID: 4

Session Assigned: Carbon Dynamics