Case Study: Avo Inversion and Processing of Ultra-High Resolution Seismic for a Windfarm Application

The development of offshore windfarms has increased worldwide. A thorough understanding of the subsurface geotechnical conditions for foundation design and installation is still more important as turbines are getting larger and available sites are further from the coast at deeper water. Ultra-high resolution seismic (UHRS) data is key in the process of developing a qualitative integrated ground model. To exploit the full potential of the UHRS data applying AVO inversion for a quantitative interpretation of geotechnical properties is a promising procedure to get an improved understanding of the geotechnical ground conditions.

A field case is demonstrated to show how improved seismic processing in the pre-stack domain of UHRS together with simultaneous AVO inversion can aid in forming a quantitative ground model. Based on the UHRS inversion results we present a method to predict geotechnical CPT parameters like cone resistance, sleeve friction and porewater pressure. These results are key to the geotechnical engineer, as they can aid foundation design and installation calculations. The results will also help to make a more informed geotechnical field campaign planning.