The Integration of 3D Seismic With the Ultrahigh Resolution Data From the Marine Survey: Recognizing and Quantifying Several Challenging Features for Subsea Production Installations in Complex Environment Offshore Brazil

摘要

A large integrated marine site investigation was conducted from 2013 to 2014 offshore Brazil in water depths ranging from 100 m to 2,900 m. High-resolution geophysical survey, geotechnical, and geologic data were collected using a variety of tools designed for deepwater applications. Approximately 4630 line-km of autonomous underwater vehicle (AUV) data, piston cores, jumbo piston cores, and conepenetrometer test data were collected. Results will be used for siting, routing, foundation design, and installation of development and production facilities. Interpretation of existing 3D exploration seismic volumes provided a regional geologic setting from the discovery wells in deepwater to the outer edge of the continental shelf shoreward and outside of the concession block. Analysis of the AUV and core data provided detailed qualitative and quantitative information to characterize and assess potential geohazards that could affect the large area where future facilities are planned. Potential geohazards identified during the integrated study include: rugged and steep topography; scarps, seafloor grooves, and mass-transport deposits associated with past seafloor failures, and potential for future failures; faults with seafloor expression; seafloor channels; and sediment waves.