Large amounts of methane either as free gas or dissolved in porewater are present in sediment deposits along continental margins. Under condition of high pressure and cold temperature, methane and other gases form ice-like gas hydrates. A focus of our research is on understanding the formation, structure and dynamics of gas hydrates in natural systems and their influence on the marine environment. Like groundwater springs on land, fluids and gas circulate through the upper sediment sequences of the seafloor and escape at so-called cold vents or cold seeps. Study objects are precipitates (carbonates, gas hydrates, and barites) and chemoautotrophic communities which are present at those seeps when methane is oxidized in the sediments.
Seafloor mapping at various spatial scales, deployment of TV-guided equipment, seafloor observation and sampling with submarines and remotely operated vehicles (ROV's), petrological, geochemical and mineralogical investigations on rocks and sediments obtained by conventional coring or drilling, use of pressure coring devices.