SS: Thunder Horse and Atlantis Deepwater Frontier Developments in the Gulf of Mexico: Paper Title - Two Assets, Two Approaches to Tackling Subsalt Imaging - Thunder Horse and Atlantis

Abstract

The BP-operated Thunder Horse and Atlantis developments are giants among the deepwater subsalt fields. It was recognized that effective development of these large fields would require a step-change improvement in the seismic imaging. Through close cooperation between asset and R&D teams, BP has pursued a two-pronged approach to deliver improved seismic imaging for these and other subsalt deepwater fields. New seismic acquisition and new processing techniques were needed to significantly improve the subsalt image. The methods of acquisition and processing applied to each field are very different and are dependent on field-specific issues that include: the timing and pace of development, existing seismic data, infrastructure, seafloor bathymetry, salt geometry, and reservoir configuration. Thunder Horse initiated an aggressive anisotropic reprocessing project incorporating three independent 3-D seismic surveys in a multi-azimuth processing sequence. Atlantis pursued a new 4-component ocean-bottom-node technology to provide uniform wide-azimuth acquisition, and then pioneered new receiver-centric processing to image the data. Both implementations yielded dramatic seismic image improvement while highlighting additional challenges.