Clair Ridge: 3D Benefits from a 4D OBN Baseline
L. Smith, M. Ball, P. Tillotson, D. Davies, M. Salt and D. Riley
Event name: 81st EAGE Conference and Exhibition 2019
Session: Seismic Interpretation - Quantitative Interpretation Case Studies I
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 1.59Mb )
Price: € 20
In 2017, BP with coventurers acquired an ultra-high-density Ocean Bottom Nodes (OBN) survey as a 4D baseline for Clair Ridge, the second phase of development of the Clair field. The acquisition density of the 100x50m receiver spacing and 25x25m shot spacing survey was a step change in BP’s North Sea ocean bottom acquisition for 4D surveillance. It was expected that the increase in acquisition density, both in terms of absolute fold, and offset and azimuth coverage, would improve the 3D image quality and seismic attribute reliability. The uplift in the final PP and converted wave PS stacks has exceeded expectations and has had a significant impact on the quality and speed of interpretation of the entire section from the shallow overburden to the reservoir. The quality of gathers and the accuracy of the measured AVO response provides an excellent opportunity to pursue reliable reservoir property prediction and early velocity anisotropy products also look promising for estimating fracture azimuth. The substantial uplift in the 3D dataset will significantly impact the static description of the reservoir and the understanding of how future flood fronts are likely to develop across the field.