Dynamic and history of methane seepage in the SW Barents Sea: new insights from Leirdjupet Fault Complex.

ABSTRACT: Methane emissions from Arctic continental margins are increasing due to the negative effect of global warming on ice sheet and permafrost stability, but dynamics and timescales of seafloor seepage still remain poorly constrained. Here, we examine sediment cores collected from an active seepage area located between 295 and 353 m water depth in the SW Barents Sea, at Leirdjupet Fault Complex. The geochemical composition of hydrocarbon gas in the sediment indicates a mixture of microbial and thermogenic gas, the latter being sourced from underlying Mesozoic formations. Sediment and carbonate geochemistry reveal a long history of methane emissions that started during Late Weichselian deglaciation after 14.5 cal ka BP. Methane-derived authigenic carbonates precipitated due to local gas hydrate

SUBMITTER: Argentino C 

PROVIDER: S-EPMC7902819 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature