oa Advances in marine seismic acquisition

Long offset wide azimuth seismic, simultaneous sources (blended acquisition) and ocean bottom nodes are technologies that have been developed in order to fulfill the goals of faster, cheaper and better seismic. In this paper we will present results from recent field tests where we have combined several of these technologies. New and improved hardware makes it possible to control the positions of both sources and streamers with very high (decimeter) accuracy. With recent engineering and processing algorithm advances, it is also possible to acquire blended data (i.e., firing sources at multiple shot locations within a single seismic record), and deblend the data efficiently. By combining source and streamer steering with blended acquisition, we can choose to double the cross-line sampling of 3D and 4D surveys, or acquire extra azimuths (WAZ) without the need to reduce in-line sampling, all in the same time it would take to acquire a conventional survey. By combining these techniques with advanced tools like Fresnel zone binning, we can also significantly reduce the need for infill shooting. In short, we get data faster, cheaper and better. The use of simultaneous sources also offers exciting opportunities when combined with ocean bottom nodes. The extra source(s) efficiently contribute to a higher trace count or reduced acquisition time. De-blending, i.e. the technology of separating data coming from several sources is a key software component in all of these approaches.