Hydrocarbons seepage into the ocean fuels chemosynthetic biological communities at the seafloor, supports the formation of new habitats through long-term precipitation of carbonate hard grounds, and potentially has a regional impact on the chemistry and biology of the overlying water column. There has been a rapid advance in the discovery of these sites, with a new appreciation for the widespread nature of hydrate and methane fueled systems at both active and passive continental margins and the recognition that geological or environmental events, such as earthquakes, submarine landslides, and ocean warming, can alter the release of sequestered methane into the ocean. These discoveries have expanded our understanding of the role and scale of methane-based processes within the earth-ocean-atmosphere system. This session seeks to combine multi-disciplinary research topics to assess the current baseline of cold seepage to the global oceans and its environmental impact. We welcome contributions including, but not limited to, geophysical surveys of the subsurface, regional mapping of bubble streams, analyses of source gases and hydrate and their fate in the water column, investigations of biogeochemical cycles at seep sites, and ecosystem-based studies of seep-driven chemosynthetic environments.