The Fault System Controlling Methane Seeps on the Shelf of the Laptev Sea

Resumo

The paper presents data obtained during the 69th and 72nd expeditions of the research vessel Akademik Mstislav Keldysh (2017, 2018). A mechanism of methane discharge that explains the localization of the seep fields in a limited area of the outer shelf and suggesting a system of deep and surface faults is proposed. Along the deep faults, gas fluid is transferred to the upper strata of the sedimentary cover, where it is accumulated below the gas hydrate stability zone and the permafrost horizon. The surface faults of the outer shelf break this caprock, creating conduits for the gas to migrate to the surface and to jet–release into the water column.