We present a method for estimating the shape of salt bodies by using ray-based nonlinear slope tomography. The data to invert mainly consist of residual moveout (RMO) observed below salt shapes on migrated common image point gathers. We compute Fréchet derivatives made of traveltime ...
While most marine baseline surveys do not use broadband techniques, increasingly more monitor surveys are being adapted to broadband techniques that often use different receiver-depth profiles (e.g., deeper or variable-depth). A regular matching filter that has been commonly used in 4D time-lapse processing may ...
In the oil rich Bohai area, Ocean Bottom Cable (OBC) acquisition has become the new trend with the benefit of operational flexibility, better illumination, better multiple elimination and better S/N for the targets at middle to deep depth. However, the presence of azimuthal anisotropy ...
Thrust complex imaging in the Timor Trough suffers from the fault shadows due to strong lateral velocity variation. We demonstrate a new workflow to tackle this. Broadband seismic data were acquired with high signal-to-noise ratio of low frequency. With broadband input, full waveform inversion ...
Receiver deghosting algorithms assuming a flat sea surface may be sub-optimal in the case of significant sea surface datum variations. We propose a method that begins by using the seismic data to calculate a sea surface profile. The sea surface profile is then provided ...
We introduce an inversion-driven free surface multiple modelling scheme based on multi-order Green’s functions. The approach optionally combines surface related multiple modelling with source designature and receiver deghosting. We demonstrate the effectiveness of the approach for peg-leg multiple suppression as well as highlighting the ...
Ghost wavefield elimination is pivotal for improving the bandwidth and image resolution for marine seismic data. Synhronized multi-level source arrays, which aim to synchronize the primary wavefield and desynchronize the source ghost, can greatly attenuate the source ghost wavefield during acquistion. However, even with ...
RTM surface offset gathers (SOG) contain subsalt events spanning the entire offset range (i.e., longer usable curvatures for tomography). RTM SOGs also have more reliable residual curvatures because each offset and azimuth group is migrated independently and does not interfere with the neighboring ones ...
We designed and implemented a practical and comprehensive workflow to mitigate missing source wavelet information and waveforms with vast spatial variation for land dynamite surveys and addressed the common challenges of acoustic-FWI application on land surveys during field data preparation.