Seismic evidence for fluid migration on the outer Chukchi Shelf, Arctic Ocean

Abstract

AbstractMethane released from shelf regions is considered to be an important contributor to climate change. Knowledge of potential emissions from specific regions is therefore critical for estimating expected climate change. To this end, we use multichannel seismic data acquired in 2011 to image the subsurface and identify upwelling gas migration structures along the outer Chukchi Shelf in the Arctic Ocean. We examine the upper 2500 ms TWT of sediments for distinct sedimentary structures and anomalous seismic velocities. The data show a wide distribution of bright spots as a consequence of the fluid migration from deeper sources throughout the study area. However, no bottom simulating reflector is identified in the study area to indicate the base of a likely gas hydrate zone. Furthermore, high seismic velocities and strong ground reflectors are not observed, suggesting an absence of submarine permafrost from the outer Chukchi Shelf.