Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Meteor	M76-3a	07.06.2008 - 13.07.2008		SE Atlantic (Limit 20?W)

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Spie? Volkhard	Fachbereich Geowissenschaften der Universitat Bremen	Walvis Bay	Walvis Bay

Ziel der Reise / Objectives of Cruise:

The main objectives of R/V Meteor Cruise M76/3a were to investigate the controls of fluid and gas migration, the accumulation of free gas in and beneath the gas hydrate stability zone, and the geochemical and microbiological interactions at the sedimentwater interface, with the help of high-resolution seismo-acoustic mapping, video observations and sediment coring on the West African continental margin. Main questions include on one hand the influence of facies, grain size, and permeability variations within the sediment; and on the other, the effect of salt tectonic deformation on gas accumulation and migration. Different lithological settings were selected for comparative multi-scale investigations with swath bathymetric, sediment echosounder, multichannel seismic, and backscatter systems as well as geological and biogeochemical sampling. The immediate products of the cruise were a complete picture of the structural and sedimentary framework; near-3D images of vent sites, migration pathways and gas reservoirs; the identification of areas of recent vent activity, an overview information for subsequent ROV work during leg M76/3b and a quantification and characterization of active vent sites and shallow gas hydrate deposits in the light of different geological conditions. A close cooperation with IFREMER, Brest allows extended expertise especially in the fields of carbonate precipitation, biogeochemistry, microbiology, biology, monitoring and modelling.

Messungen / Measurements