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The deepwater Gabon South Salt basin represents one of the last underexplored regions of the West African continental margin. A new 25,000-sq km (9,653-sq mi) broadband 3D seismic survey was recently acquired in the basin as part of an integrated eoscience program to support the Gabonese Republic’s new deepwater 11th Licensing Round. Given the high-quality results seen so far, final results are expected to be a significant resource for explorationists to de-risk this promising exploration arena.

Removing the band limitation by the seismic source wavelet may further enhance the spatial resolution of seismic images after de-ghosting and amplitude attenuation compensation. In this abstract authors propose a new de-signature method that incorporates structural conformity constraint and sparse regularization into the inversion-based deconvolution to achieve better signal-to-noise ratio and geological coherence in the resolution-enhanced output images. The new method was applied to field data; and compared with an inversion-based method without sparse regularization and structural conformity constraint, the new method gives cleaner and more coherent seismic images meanwhile with broader bandwidth. Acoustic impedance inversion was carried out after de-signature, and a more detailed and coherent impedance volume was obtained.

While for reverse time migration deconvolution imaging condition offers the strongest possibility for source designature and compensation of illumination, cross-correlation-based imaging conditions are the most widely used due to their high stability. We propose here a general theoretical frame and practical solution for stabilizing deconvolution-based reverse time migration. Our approach involves an optimization scheme regularized by a set of constraints. The proposed constraints insure both high-resolution and removal of low frequency migration noise arising in case of diving or reflected waves in the background model. We show the improvement obtained with our approach on synthetic and real datasets.

Porosity estimation using EMERGE for an onshore Abu Dhabi field. CGG processed the seismic and it was followed by seismic inversion. The P-impedance was further used in predicting the porosity. This porosity result very helpful to client to well planning and drilling to target the best porosity in the reservoir. Porosity result matched very well with the new well's acquired porosity data.

Ocean Bottom Cable (OBC) acquisition has become the new trend in Bohai area 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 orthorhombic anisotropy causes severe challenges in imaging with Wide Azimuth (WAZ) OBC data, particularly fault imaging which is sensitive to velocity accuracy. Fault imaging can be smeared and fault shadows can be observed within complex strike-slip fault systems if the azimuthal dependency of wave propagation is not properly honored and velocity variation across faults is not properly modelled. To address these challenges encountered in imaging of Luda field with WAZ OBC data, we have developed a practical orthorhombic full-waveform inversion approach to invert for a high-resolution model in the presence of orthorhombic anisotropy. We will demonstrate that our orthorhombic FWI approach can produce high resolution velocity model which reconciles the structural discrepancies between seismic images from different azimuths, and significantly improves the focusing of the fault imaging and the imaging of structures beneath the faulting system. The combined effect of these improvements gives a clear uplift in the final seismic image.

We discuss a feasibility study to access the 11,500 well headers and 450,000 documents from the United Kingdom Continental Shelf (UKCS) that were released by Common Data Access Limited. A cost-effective solution based on emerging machine learning technology “taught” and guided by data-management experts supports the reliable indexing and cataloging of these forms of data, paving the way for much more reliable E&P business decisions in the future.

The detection and mapping of fractures in migrated poststack 3D seismic data depends on the resolution and signal-tonoise ratio of the data in the seismic volume. A discussion of resolution problems and the limits of resolution in post-stack 3D seismic data, and structurally-oriented post-stack coherent and random noise filtering is followed by descriptions of a Fracture Density attribute and of the extraction of fracture orientations.

Seismic Interference (SI) has long been a problem for seismic data acquisition in congested areas such as the North Sea, but thanks to advances in processing algorithms and new cooperative management techniques developed in conjunction with Statoil and RIL, downtime or time sharing due to SI has been effectively eliminated.

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 spaced streamers, and one source vessel with two or more sources. The source vessel is shooting on top of the seismic spread which facilitates acquisition of zero-offset, as well as split-spread data. This creates a unique illumination of the subsurface, especially in the shallow but also to intermediate target depths. The solution has been developed and tested in close cooperation between CGG and Lundin through a comprehensive modelling and field trial program involving a series of safety and mechanical tests and also a small 3D test survey.