In the search for continued petroleum resources on the NCS (Norwegian continental shelf) and in other regions around the world, geologists and geophysicists working with imaging of the subsurface agree that we need better data.
Nodes Pros and Cons
The attraction of OBS is obvious. By placing receivers on the seafloor and decoupling the source from these receivers, it is possible to record rich azimuth data, potentially giving superior illumination of geologically complex exploration targets. On the downside, the data is costly and slow to acquire and process.
.......PGS was convinced that they could offer a better overall solution with advanced towed-streamer technology, including the widely celebrated GeoStreamer.
"The answer was in fact simply the next step, as it incorporates all the acquisition solutions applied on our groundbreaking 2018 survey in the Barents Sea, combined with multi-azimuth acquisition. Wide-towed sources, as well as longer and denser streamer spreads, are enabled by our high-capacity Ramform vessels," Osnes says.
"We discussed the need for better and faster data with many oil companies worldwide and received a lot of support for the ideas presented. The most popular solution for the NCS was acquiring GeoStreamer data in three different shooting directions, with wide-towed sources and denser streamer spreads."
According to (Osnes), there are two main advantages compared to OBS: considerably lower cost and significantly reduced turnaround time. While the former mainly has to do with using only one vessel in a shorter time span, the latter applies to both acquisition and processing, meaning that exploration teams will get much-needed data much earlier. On top of that, there is less environmental impact and reduced risk of area conflicts with fisheries (vessels).
The full version is not yet available online. However, you can read more about GeoStreamer X in our recent news release for GeoStreamer X Viking Graben, and view the quality of data produced with a single azimuth using this acquisition configuration in our case study on the Barents Sea solution.
This depth slice from our 2019 Hammerfest survey was created using single-azimuth data acquired with a similar setup as the ongoing Viking Graben GeoStreamer X survey. The details and large velocity contrasts captured in the velocity model allow accurate imaging without distortion effects caused by the shallow heterogeneous overburden in the Barents Sea.
