Rich Azimuth Dual Triple-Source Simultaneous Shooting West of Shetland

We discuss the survey planning and provide results from a marine acquisition conducted northwest of the Shetland Islands. The survey was designed to image multiple targets from shallow Tertiary and Cretaceous plays, through to complex fractured Devono-Carboniferous reservoirs. Marine acquisitions are typically conducted along the direction of structural dip. In this case, this was not possible due to the proximity of the survey to the Shetland Islands. In an attempt to address this problem, triple sources were deployed to decrease the spacing between inlines and improve sampling along the structural dip direction. In addition, a second vessel was deployed broadside in a rich-azimuth configuration to increase offset coverage in the y-direction and to help undershoot sills and dykes present in the area. Activating so many sources sequentially would significantly decrease fold and increase noise levels of the data. After careful scenario testing and de-risking, which involved blending and deblending conventional data in various ways, the decision was made to acquire the data with simultaneous shooting. Data after deblending and depth imaging highlight the benefits provided by this rich-azimuth approach.