A Geophysical Review of the Seabed Methane Seepage Features and Their Relationship with Gas Hydrate Systems

Seabed methane seepage has gained attention from all over the world in recent years as an important source of greenhouse gas emission, and hydrates are also regarded a key factor affecting climate change or even global warming due to their shallow burial poor stability. However, relationship between seabed hydrate systems is not clear although they often coexist continental margins. It significance clarify better understand contribution deeper hydrocarbon reservoirs for flux leaking seawater atmosphere by natural seepages at seabed. In this paper, geophysical examination events been conducted, nearby stability zone relevant fluid migration pathways have interpreted modelled using seismic data, multibeam underwater photos. Results show that sites manifested flares, pockmarks, deep-water corals, authigenic carbonates, pingoes seabed, most which closely related vertical structures like faults, chimneys, mud volcanoes, unconformity surfaces located landward limit (LLGHSZ) where dissociation may released great volume methane. Based on comprehensive analysis these features, three major types classified according spatial with location LLGHSZ, than LLGHSZ (A), around (B), shallower (C). These can be further divided into five subtypes considering whether not. We propose subtype B2 represents type high density large massive focused vigorous LLGHSZ. classification result research, more measures should taken predict prevent ocean change.