Technical Content

We investigated how current least-squares reverse time migration (LSRTM) methods perform on subsalt images. First, we compared the formulation of data-domain vs. image-domain least-squares migration (LSM), as well as methods using single-iteration approximation vs. iterative inversion. Next, we examined the resulting subsalt images of ...

The importance of inverting jointly velocity and density parameters in full waveform inversion (FWI) is well established. In a former work we had proposed an innovative preserved amplitude FWI allowing improving the convergence rate of FWI. It was derived from preserved amplitude reverse time ...

Spectral broadening of migrated and stacked seismic images is a common method to enhance interpretability of reflection data. In this paper we propose a prestack AVA compliant spectral broadening approach based on non-stationary wavelet deconvolution. The algorithm employs AVA coupling in the prestack domain ...

Posing migration as an inverse or a least-squares problem can improve the quality of imaging. This class of techniques can resolve illumination issues and improve focusing. Standard iterative least-squares imaging can be expensive and results are often compromised. We present a procedure using matching ...

An integrated geological and petrophysical workflow was used to evaluate the Jurassic shale plays in southern England. It illustrates how sedimentological and electrofacies interpretations were integrated with QEMSCAN data to significantly improve petrophysical interpretations and TOC estimates from logs using the CARBOLOG method. Reservoir ...

Traditionally, the regularization step is performed independently for each time-lapse vintage. This disregards any geometrical limitations imposed by different surveys. Here we recast the regularization process as a minimization problem with model-space constraints. These constraints couple geometrical relations between surveys to improve repeatability. We ...

Until now, noise attenuation and interpolation processes based on rank reduction needed spatially regular, or at least binned, data. Here, we show how the low-rank signal model in joint low-rank and sparse inversion (JLRSI), a recently proposed convex optimization framework for simultaneous random plus ...

Simultaneous shooting increases acquisition efficiency by activating more than one source at the same time. This introduces blending noise that typically needs to be removed before data processing. We present a new deblending algorithm based on iterative annihilation filtering. The strategy attenuates coherent energy ...

Remotely detecting information about fractures and the stress field is an important objective in the development of unconventional and tight hydrocarbon reservoirs. Fractures and stress cause the earth to become anisotropic which is seismically observable. By observing the P-wave seismic amplitude variation with offset ...