Using Shallow Hydroacoustic Data to Image Seafloor Mass Transport Deposits on the North West Shelf of Australia.

Abstract:

During May and June 2017 the German research vessel Sonne sailed from Darwin to Perth collecting sediment cores for the SO257 expedition Western Australian Climate History from Eastern Indian Ocean Sediment Archives (WACHEIO). During the voyage a number of high-resolution shallow seismic lines were shot at strategic locations along the transect, in addition to continuously acquired surface bathymetric and sub-bottom profiling data (Parasound). These shallow datasets identified a number of previously unknown mass transport deposits at locations around the transect, including both gravity (soft-sediment) and tectonically-driven. Seismic acquisition, although entirely opportunistic within the confines of the expedition objectives, correlated extremely well with Parasound and bathymetry profiles, yielding a rich new dataset for the North West Shelf. The seismic data in particular add significant resolution to standard industry 2D seismic lines in the same areas. This poster presents the results of the combined shallow hydroacoustic datasets, and links them to known large-scale mass transport deposits and potential neotectonic driving mechanisms.