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.
Acquisition of Utsira was completed on schedule in autumn 2019 and now processing of the northern half of its landmark ocean-bottom node (OBN) multi-client survey in the Norwegian North Sea is also complete and has been delivered to pre-funding customers. Data processing will be complete for the southern half of Utsira in September 2020.
The total number of nodes deployed for the survey was 143,567 and total shots was 3,942,230. The size of the input data for processing of the entire survey was 1.5 petabytes. To put the project into context, the data collected is equivalent to a typical 520,000-square kilometer marine survey - enough to cover an area the size of Spain.
Our OBN data is defining a new reference point for quality subsurface imaging which will be imperative for E&P companies as they seek to maximize the life of producing fields and production facilities.
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.