Oil & Gas

Shallow water regions of the Gulf of Mexico hold promising petroleum prospects but pose imaging challenges due to complex overburden velocity in the Mesozoic section. Traditional sparse OBC surveys struggled to resolve these features. This technical article highlights a Time-lag Full-Waveform Inversion (TLFWI)-driven velocity model building (VMB) approach that significantly improved imaging of faulted sediment basins, allochthonous salt formations, and carbonate blocks. Combining TLFWI with FWI Imaging unveiled deep Mesozoic structures, enabling a clearer geological interpretation of the basin and unlocking new exploration potential.

While Land Full-Waveform Inversion (FWI) has been applied to seismic data in Oman, its use has typically been limited to low-frequency updates for migration. This technical article presents a breakthrough application of acoustic FWI up to 35 Hz, enabled by optimized data conditioning, initial model preparation, and velocity inversion. The resulting FWI Image, derived from the velocity model, delivers a superior view of the complex fault system, surpassing conventional imaging methods by leveraging the full wavefield and least-squares fitting across all frequencies.

Accurate near-surface imaging in the Middle East is challenging due to strong velocity contrasts in the shallow geology. This technical article highlights the application of Elastic Full-Waveform Inversion (FWI) of surface waves, leveraging low-frequency virtual data from 3D interferometry and active surface waves to build a detailed shear velocity (Vs) model. Compared to legacy models, the updated Vs model delivers improved subsurface resolution, simplified geological structures, and better alignment with well markers, enhancing overall seismic imaging.