General Geology - Marine Geology

Research topics

Large amounts of methane either as free gas or dissolved in porewater are present in sediment deposits along continental margins. Under the condition of high pressure and cold temperature methane and other gases form ice-like gas hydrates. A focus of our research is to understand the formation, structure and dynamics of gas hydrates in natural systems and their influences 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 that are present at those seeps when methane is oxidized in the sediments.

Burning methane hydrate and white gas hydrate in the sediment.

Working Areas

Cold seeps and gas hydrate deposits at active and passive continental margins: South-China Sea, Hydrate Ridge off Oregon, Gulf of Mexico, Black Sea, and Mediterranean.

Methods

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.

Multicorer recovering sediment cores under in situ pressure.