PARIS – CGG (NYSE:CGV) is performing a large pre-stack depth migration (PSDM) processing project to upgrade its Cornerstone 3D long-offset data taken over the UK central North Sea.
The company will use its multi-layered tomography technology TomoML to build a TTI anisotropic velocity model, calibrated with more than 120 wells throughout the region.
CGG additionally will apply its latest ghost compensation processing technique, intending to extend the frequency bandwidth and to improve the resolution of the conventionally acquired data, providing a contiguous, broadband, depth-migrated dataset.
The company is also applying its BroadSeis variable-depth streamer technology with BroadSource to extend the Cornerstone CNS 3D dataset by 5,500 sq km (2,123 sq mi) in quadrants 29, 30, and 38. The main aim is to improve imaging of thin and complex formations in the southern margin of the Central Graben, from the Carboniferous-Permian section through the Jurassic and up to shallower Paleogene targets.
Finally, CGG plans a further 3D seismic program, to cover HP/HT reservoirs in the deep part of the Central Graben. It will tailor this survey to optimize imaging of both deep and shallow targets, with an east/west orientation. The results, combined with the north/south acquisition of the underlying Cornerstone dataset, will allow dual-azimuth processing of the overlap, and this is expected to assist imaging of deep, complex, and highly faulted structures.