CGG has revealed that Nebula 3D Phase I is nearing completion and acquisition will soon commence on Phase II, the company said on Oct. 27.

Nebula 3D is a large, long-offset BroadSeis survey located in the prospective Campos and Santos Basins offshore Brazil. Phase I covers approximately 17,700 sq km on the southeastern side of the survey area providing 3D data coverage where currently no other 3D data exists. Phase II covers approximately 10,000 sq km on the northern side of the survey area with underlying broadband datasets that will provide input for dual-azimuth imaging.

The Nebula Phase II dual azimuth data will better illuminate pre-salt events and address significant challenges posed by thick volcanic layers in this portion of the survey. CGG’s industry leading Subsurface Imaging Center in Rio de Janeiro will employ state-of-the-art processing technology including interbed multiple attenuation and proprietary time-lag FWI to dramatically improve the velocity model and produce clearer, more focused subsurface images of this prolific pre-salt area.

Commencement of Phase II is expected early December and acquisition will be carried out by Shearwater’s Oceanic Sirius. Fast track results are expected fourth-quarter 2021 and final products are expected first-quarter 2022, which will include a TTI Kirchhoff PSDM, a TTI RTM 45Hz and a LSRTM 45Hz.

“The Brazilian Pre-Salt is the largest worldwide oil discovery in the last decades and it is the most important exploration play in the world, highly coveted by all supermajor oil companies and by new players willing to enter in this prospective sector,” Sophie Zurquiyah, CEO of CGG, said. “This addition to our already very large 3D multiclient library in the Santos and Campos basins underlines our commitment to offering the industry ultramodern data sets to support optimized exploration and development of the entire pre-salt area.”