3D Seismic and Multidisciplinary Investigations of Cold Seeps along the Hikurangi Margin, North Island, New Zealand

Gas hydrate occurrences are known from continental margins world-wide. Mainly Methane gas is bound in solid phase in the sediments when stability conditions of temperature and pressure are given. Unusual but often observed exceptions within the gas hydrate stability field are gas migration pathways that enable gas transport through the hydrate stability field. Such migration pathways are known as cold seeps and indicated by active gas expulsion at the seafloor and / or by carbonate precipitations if they did exist over long time periods. The accretionary Hikurangi Margin hosts a large number of active cold seeps along the ridges of the accretionary wedge. Multidisciplinary marine investigations have been undertaken to analyse lifetime, activity and internal structures.