Characteristics and the controlling factors of sedimentation in deep-sea slopes: an example of the Roebuck Basin, Australia

Understanding deep-water slope depositiona is of great significance for deep-water oil and gas exploration and development as well as deep-water geohazard protection. To reveal the characteristics and controlling factors of the Neogene deep-water slope deposition in the Roebuck Basin, Australia, the stratigraphic sequences of slope deposition were delineated by using high-resolution 2D seismic data, and seven third-level sequence interfaces and six seismic sequences were recognized on seismic section. Results show that the Neogene in the study area are mainly the sedimentary sequences of progradational, aggradational-progradational, and retrogradational sedimentary sequences. The deep-water area of the Roebuck Basin developed three types of slope deposits: progradational carbonate rock deposits, siliceous debris deltaic deposits, and olistostrome deposits. The deep-water slope deposits were controlled by various factors. In the Middle Oligocene and the Late Miocene, the slope deposits were controlled by the relative sea level fluctuation, paleoclimate, and material supply, while after the Late Miocene, with the collision of the northward drifting Australian plate against the Banda Island Arc, the deep-water slope deposition was mainly controlled by tectonic activities.