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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.

We applied full waveform inversion to a seismic dataset from offshore Gabon. This dataset features complex geology such as diapirism, shallow gas pockets and dewatering faults. We show the results on a large production-size swath from an advanced full waveform inversion method based on the L-BFGS optimization algorithm. The updated velocity model highlights an uplift in resolution and a consistency with the geological features observed in the depth migrated stack. The benefits include identifying features and faults in the overburden and improved top-salt characterization. These result in better imaging in both the post- and pre-salt regions, as well as a velocity model than can be used to aid the geological interpretation.

Numerous evaluations, conducted on various sites, converge towards a shared conclusion: the geophysical value of an acquisition is primarily driven by the density of traces acquired in the field. To confirm this principle also applies in North Africa, ENI and CGG agreed on a technical collaboration. The objective of the collaboration was to demonstrate, on a crew operating in South of Tunisia, that, without additional equipment, using modern high productivity schemes it was possible to efficiently increase the conventional Trace Density by a factor of 10 to 50 with a significant increase in geophysical value all along the processing, imaging and interpretation steps.

In this paper we introduce an AVO QC workflow which was initially designed for ultra-dense land datasets. Its purpose is to monitor the AVO behavior at key steps of a processing sequence on the full area of interest and not only limited to a well neighborhood. The workflow, based on data reduction, consists in the creation of a reliable AVO model that can then be compared to the seismic through different measurable indicators. After some basic interpretation on the whole processed area, using maps and statistics, the processing step is assessed in terms of ‘AVO-friendliness’. If validated, the sequence can be continued and if not, it must be revised. This AVO QC workflow proves the AVO-friendliness of a process. The robustness of the workflow makes it potentially applicable to all types of 3D datasets.

A case history in West Texas, in the Permian Basin, of a non-exclusive seismic imaging project spanning acquisition, processing and reservoir interpretation. Located in Howard and Glasscock counties, the Hobo non-exclusive seismic survey aims at imaging and quantitatively interpreting the Spraberry and Wolfcamp formations.

We demonstrate a recently developed method for computing tomography model uncertainties and mapping them into the migrated domain. The method generates after the final tomography a series of equi-probable velocity model perturbations within a standard deviation confidence level. This allows computing standard deviation-like attributes for velocity and anisotropy parameters and for key horizons. An application to West of Shetland dataset highlights the interest of the estimated uncertainties.