Optimal Acquisition and Processing Strategies for Successful UHRS Pre-Stack Inversion

Pre-stack inversion of seismic reflection data has been used by geophysicists to quantify the subsurface for over 20 years. While the technique has been applied extensively on low frequency, exploration seismic data (<250 Hz) to successfully characterise reservoir properties and hydrocarbon potential, it has only recently been introduced to ultra high resolution seismic (UHRS) to build quantitative ground models of geotechnical properties for the offshore wind farm (OWF) industry. While the basic physics of the seismic reflection method are the same for UHRS as they are with their low frequency counterparts, unique challenges become apparent when looking at the ultra high frequencies and resolutions encountered in OWF seismic data. Historically, with the major requirement from a multichannel UHRS project being a rapid turnaround, processed stack product for interpretation, these challenges have been largely ignored due to the power of stack to reduce pre-stack imperfections. However, to maximise the value of OWF seismic data through quantitative geophysics, these unique challenges need to be adequately addressed and thus key aspects of UHRS acquisition and processing need to be carefully considered with the final objective of the data - pre-stack inversion - in mind.