Technical Content

Difficulties in processing land seismic data often arise due to insufficient sampling of the wavefield. Fully unconstrained simultaneous shooting offers a way to substantially increase productivity and hence source densities, leading to improved sampling of the wavefield. In order to achieve this we must ...

Full waveform inversion (FWI) is a method of velocity estimation which minimizes the misfit between recorded and modeled data, the parameters of the minimization being the velocity model. If the velocity model is smooth, then only the refracted waves are modeled and used, if ...

Time-lapse seismic processing in carbonate fields having complex geology and in difficult seismic contexts requires highly specialized teams for success. Our field case has a flat structure, a poorly-imaged but highly reflective sea bottom and is covered by towed-streamer data in about 60m of ...

Over the recent years, numerous case studies have highlighted the strong link between the geophysical value of seismic acquisition and the maximization of two metrics: trace density (expressed as the number of source-receiver pairs per square kilometers) and frequency bandwidth (expressed in octaves). Here ...

This paper describes a successful reservoir characterization workflow where geostatistical inversion was first carried out to characterize caves and vugs, and then azimuthal inversion was used to obtain fractures strike and density. It improves the precision of reservoir prediction, and effectively characterizes the distribution ...

We present a method to estimate and correct the phase of broadband seismic data in the low-frequency range using the tomography velocity model as an analogy for subsurface geology. The high-resolution velocity model is obtained from travel-time tomography and therefore has minimal influence from ...

In recent years there has been tremendous progress in the resolution and accuracy that can be obtained in seismic images. Several techniques are now available to achieve a high-definition final image. In the Cap-Boujdour dataset from offshore Morocco, the imaging is challenging due to ...

The absorption effect caused by the anelastic nature of earth leads to attenuation of amplitudes and distortion of phases for seismic wave. The so-called Q factor has to be compensated for correct imaging. We propose least square Q-Kirchhoff migration (LSQPSDM) in which absorption is ...

In this paper we present a new source-over-cable marine seismic acquisition technique that initially was developed to meet imaging challenges of the Loppa High in the Norwegian Barents Sea. Two seismic vessels operate in tandem; one streamer vessel towing a spread of deep, densely ...