For E&P companies, a key driver is to maximize the life of producing fields and production facilities. In times of declining reserves, Infrastructure-led exploration (ILX) is more important than ever. Ocean bottom node (OBN) technology has been proven to deliver the highest quality seismic data. As the cost of acquisition and processing of this data reduces, OBN seismic becomes competitive compared to traditional seismic methods.
TGS is planning to acquire dense OBN data in the North Sea for improved understanding of the subsurface. Acquisition of Utsira has already begun and is expected to be concluded in the autumn of 2019.
A successful and efficient dense OBN multi-client project can pave the way for similar initiatives in the Gulf of Mexico, Brazil and other regions, as well as further expansion in selected areas on the Norwegian and UK continental shelves
Meeting complex geological challenges
OBN is the ultimate imaging tool to help operators overcome complex geological imaging challenges. With full azimuth acquisition, complex geology can be illuminated in all directions and structures and attribute variations can be properly understood. Greater than ten times higher fold significantly improves the signal-to-noise ratio, as well as the ability to distinguish between structure and attribute anomalies which the interpreter can believe in or not. Other advantages include ultra-long offsets, measurement of the full wavefield and measurement of both P- and S-waves for better characterization of fluids in a reservoir.
Despite the reduction in cost of alternative seismic acquisition, OBN has prevailed and grown its presence in the proprietary acquisition domain during the last few years. This is because the recent closing of the price differential between streamers and OBN is opening up large multi-client OBN investment opportunities in areas with complex geology, a conglomerate of license holders and acreage turnover.
TGS is positioning itself to take a lead on multi-client OBN adaption and grow this market over the next decade. OBN is defining a new baseline for quality subsurface imaging using full azimuth, ultra-long offsets, small bin size and exponentially more measurements per area.