The role of geophysics in offshore geotechnical site characterizations in the energy transition era: From oil and gas to renewables

Offshore geotechnical site characterizations aim to assess the engineering properties of shallow sediments/soils (around the top 400 ft below the seafloor) and to quantify their geospatial variability to ensure the safe, reliable, and economic design of offshore infrastructure. The current state-of-the-art workflows for offshore site characterizations rely heavily on geophysical and geotechnical (G&G) data integration. This integration essentially guides the planning and execution of geotechnical site investigations based on subsurface conformity and variability (Aubeny et al., 2013; Doyle, 1998; Jeanjean et al., 2006; Newlin, 2003). Without this integration, it would be difficult to optimize soil borings, determine seabed-founded structure locations, select in-situ testing locations, and it would be cost-prohibitive to conduct the otherwise necessary closely sampled geotechnical investigations over large areas. Therefore, the motivation of this abstract is to provide thoughts on further improvement of the quantitative G&G integration with a final goal of characterizing the geospatial variability near seafloor subsurface for the geotechnical engineering purpose. Brief introduction on the current challenges and opportunities for future improvements are provided.