New Zealand Cold Vents and their association with gas hydrates and their impact on local, regional and global methane and carbon cycles

A project in cooperation with the network project COMET

Applicants: Dr. Jörg Bialas, Dr. Peter Linke

Project period: 01.10.2006 - 31.03.2009

Aim of the FS SONNE cruise New Vents – New Zealand Cold Vents - is the investigation of both local and regional transport processes of methane and the characterisation of facies at cold vents and deposits of gas hydrates at the Hikurangi margin. The Hikurangi margin is an accretionary complex at the eastern coast of the Northern Island of New Zealand. During the 54 working days, extensive geophysical, geological, geochemical and biological probing were conducted on known vent sites. This included the first detailed geochemical investigation of these vents and gas hydrate deposits, which have been identified by the presence of BSRs. We furthermore wanted to comprehend and quantify the influence of naturally released methane on metabolic processes at the seafloor and in the water column. This required the analysis of fluid compositions, of the depths of origin of these fluids and of biochemical microbial processes at the sediment surface. High resolution seismic measurements (Deep Tow) completed and supplemented the investigation.