ABSTRACT
Geophysical data acquired as part of the hydrocarbon field assessment will prove of sufficient resolution to identify key seabed features and major stratification changes for the desk study. Geophysical investigation comprising data from 3D, shallow seismic and side-scan sonar surveys will give an indication of the local seabed and soil conditions over a large area. A typical investigation will include: bathymetry for water depth and seabed gradients; seismic reflection data for sub-bottom stratigraphy; side-scan sonar for seabed topography such as pock marks and ice gouges. Geotechnical investigations usually involve a combination of offshore work, followed by onshore laboratory testing of samples recovered from offshore and a subsequent interpretation of the test results to yield engineering design parameters. The theory behind the various techniques of geophysical measurements and interpretation of data is extremely complex, forming a separate scientific discipline. The aim is limited to a brief description of the different types of equipment that are available, and their capabilities.
