Improve PZ summation and reduce the receiver ghost and free surface-multiple noise contamination.
Published: 05/10/2017
Published: 05/10/2017
Significant recent advances in imaging technology range from acquisition to earth model building, signal processing, and migration algorithms. For example, wide-azimuth and Dual Coil Shooting multivessel full-azimuth acquisition have become the preferred acquisition methods because they notably improve illumination and signal-to-noise (S/N) ratio. Similar developments in anisotropic velocity model building and the use of full-waveform inversion (FWI) have further refined the model and reduce seismic data uncertainty. Reverse time migration has become the standard migration algorithm, resulting in great improvement in salt geometry accuracy. However, despite these advances, the interpretability of subsalt images remains a major challenge for deepwater subsalt oil exploration in many areas, such as basins of the Gulf of Mexico, Brazil, and West Africa, especially where steeply dipping targets are directly beneath complex salt canopies. The main issue to resolve is inadequate illumination caused by the salt geometry and sharp contrast at the sediment/salt interfaces. In poorly illuminated areas, undesired events and strong coherent noise, such as residual multiples and migration swings, can overcome the weak signal to the extent that it cannot be observed in the image. Over the past few years WesternGeco has introduced several technologies that significantly improve subsalt images. Join this webinar to learn how IGIE interpretation-guided image enhancement, converted wave attenuation (CWA), shot selection migration, and interpretation guided selective stacking (IGSS) boost the desired signal and suppress unwanted noise. Mohamed Hegazy, Area Geophysicist at the Schlumberger Geosolutions Center in Houston, has 11 years of experience in seismic data acquisition and processing. He joined WesternGeco as a field geophysicist, advancing to chief field geophysicist. Since becoming an area geophysicist in 2013, he has primarily worked on depth imaging projects in the deepwater Gulf of Mexico.