Exploiting Exploration Measurements for Drilling Hazard Identification: A Case Study from the West of Shetlands

Summary To identify subsurface drilling hazards, higher resolution is the key criteria. While some compromises are made in seismic exploration, typically designed to image deeper reservoirs in an efficient manner, we show that, with specialised processing and imaging, exploration measurements can be used to identify geohazards in the shallow section. We present here a study from the Westray seismic survey offshore West of Shetland that was primarily designed to promote exploration in the area with a broadband acquisition design. These data were reprocessed with finer temporal and spatial sampling to provide a higher resolution subsurface image and were complemented by detailed depth imaging using full waveform inversion. This image provided a substantial uplift in the interpretability of shallow subsurface features that are potential hazards for drilling. To complement this, we also demonstrated the use of multiples for nearer angle imaging of the shallow subsurface, further improving resolution. We also investigated the potential of near-field hydrophone measurements for even higher-resolution subsurface imaging