Late Quaternary paleoceanography of Vestnesa Ridge, Fram Strait: Ostracode species as a potential indicator of cold seep activity

Past intensity of methane release from deep-ocean methane hydrates continues to be chal-lenging to reconstruct reliably. Here, we used fossil ostracode fauna paired with foraminif-eral & delta;13C values in a marine sediment core from Vestnesa Ridge, western Svalbard margin, to reconstruct methane seepage activity during the late Quaternary and to examine faunal response to deglacial climatic changes. Benthic foraminiferal & delta;13C values indicate methane seepage activity was relatively strong during marine isotope stage 2, corresponding to a high percentage of the ostracode Rosaliella svalbardensis in the assemblage. In contrast, this spe-cies was absent under conditions of no or very strong seepage of methane. Faunal changes in other taxa were more related to global climate changes regardless of the seepage activity. This result indicates that Rosaliella svalbardensis is a potential new useful proxy for past methane release.