Equinor has awarded CGG a major contract for the seismic imaging of its Bacalhau 3D ocean bottom node (OBN) survey covering 409 sq km currently being acquired in Brazil’s deepwater Santos Basin.
The project is already underway at CGG’s Rio de Janeiro subsurface imaging center where its team is using imaging technologies, including reverse time migration, time-lag full-waveform inversion (TLFWI) and interbeds multiple attenuation, to address pre-salt illumination challenges caused by the presence of very thick stratified salt.
"Combining OBN data with TLFWI will result in more detailed and reliable velocity model building and imaging, bringing geological insight at post-salt, intra-salt and, most importantly, at pre-salt levels. The resulting high-quality subsurface image will reduce uncertainties and enable a better structural interpretation to guide future drilling plans and development of the world-class Bacalhau field," CGG said.
Final products for the fully imaged dataset are expected to be delivered within ten months after the survey is scheduled to complete in May 2021, the French seismic data firm said.
Bacalhau is a project in 2,000 meters water depth in the Brazilian pre-salt area, located in the Santos Basin. It is Equinor’s deepest high-pressure field, consisting of two licenses, BM-S-8 and Norte de Carcará. The field was discovered in 2012, and Equinor—now operator and owner of a 40% project stake—purchased it from Petrobras in 2016. Partners ExxonMobil and Petrogal Brasil hold 40% and 20% stakes respectively.
Bacalhau (Carcará) will be the first greenfield development in the pre-salt by an international operator. Japan's MODEC will deliver an FPSO for the project.
Drilling contractor Seadrill said in April it had secured a four-year firm contract with four one-year options for the West Saturn drillship with Equinor for work on the Bacalhau field.