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3D VSP data provides a unique opportunity to improve image resolution and fault definition in the vicinity of a well. However, the processing and imaging of VSP data requires special accommodations for its distinctive acquisition geometry. In this abstract, we demonstrate two key VSP pre-processing steps that greatly impacted the final image from the Mad Dog 3D VSP data, including XYZ vector field reorientation based on 3D elastic finite difference modelling, and shot-to-shot directional de-signature using near field hydrophone data. We also demonstrate how utilizing the multiple energy - in addition to primary - extends our capability to image the shallow overburden.

In an increasingly complex and challenging environment, CGG is building effective links between academia and industry and utilising new techniques to enhance hydrocarbon exploration success in a world where oil prices are highly volatile. In this environment there is increasing focus on risk reduction and increased exploration efficiency. In synergising the use of newly available technologies, research and an integrated geoscience approach, CGG is ensuring the future of hydrocarbon exploration. This abstract is for a poster presentation, highlighting the technical highlights of an early career geoscientist and the the efforts CGG is making to ensure the future of hydrocarbon exploration.

The Amplitude Versus Azimuthal AVAZ analysis has proved to be an important tool for characterizing fracture distributions and orientations of hydrocarbon reservoirs. This paper is aiming at the application of this tool for characterizing the fractures in Bahrain field reservoirs. Better understanding of faults and fractures distribution is essential to optimize EOR strategy and reservoir management. Regional analysis is possible by looking at faults distribution characterized by structural attributes analysis validated by regional stress and geological information. The investigation at local scale is more cumbersome but an Amplitude Variation with Azimuth (AVAz) method based on azimuthal Fourier Coefficients (FCs) proves to be a simple and powerful tool to characterize fractures distribution validated by FMI data. The anisotropy information was then used to update and improve the reservoir model long production history matching.

A case study of Oligocene-Miocene sediments in East Java Basin, Indonesia. The work look into the depositional setting and paleogeography of subsurface by removing the struture in 3D seismic. The result have been correlated with regional geology and outcrop analog. The work is done using CGG GeoSoftware's InsightEarth PaleoSpark.

We present a FWI case study from offshore Gabon of an extremely large dataset covering an area ~25,000 km2, demonstrating that FWI can be applied to this size of survey in a timely manner. The history of the South Gabon basin is complex, leading to a rich geological picture today and challenging velocity model-building process. FWI is able to help with this process and the resulting velocity model reveals features that improve the migrated image. In addition, the detail in the FWI velocity model is shown to aid the geological interpretation by highlighting, amongst other things, the location of shallow gas pockets, buried channels and carbonate rafts.

The success of any broadband survey is dependent upon the accuracy with which acquisition and environmental factors are compensated for in processing. Such compensation ideally involves directional source designature and deghosting along with receiver deghosting. Traditionally, receiver deghosting is applied in the shot domain, and directional designature in the receiver domain. We introduce a robust algorithm working in the joint shot-receiver domain that simultaneously corrects for source and receiver side effects in a single process. The algorithm is shown to produce broadband results with improved spatial consistency compared with sequential directional designature followed by receiver deghosting on a North Sea dataset.

Abstract focusses on the LiveLand ESA IAP project and summarises how earth observation, weather forecast and GNSS can assist with the challenges transport operators across Scotland experience in relation to landslides and ground deformation along transport routes.

3D seismic data is only geophysical data which has good lateral sampling. Therefore, the use of seismic data to predict elastic properties away from a well is a widely used process. However transforming these elastic properties into geomechanical and other reservoir properties requires integration of different data sets (e.g. wireline logs, core and cuttings) at various scales. The integration of all data sets is essential for de-risking seismic amplitude supported interpretations. This study demonstrates how this approach and methodology was used to help predict important engineering properties in 3D space and away from any well control. The final inverted volumes were used to pick minimum intermediate casing points and, to predict maximum and minimum mud-weights both of which provide significant capital savings in casing design and/or lost bottom hole assemblies.

In this paper we present a practical extension of earlier work on the estimation of anisotropy parameters from isotropic techniques. We will take a closer look at the implications of working with effective elastic parameters in anisotropic (TI) seismic reflection inversion. In particular, for HTI media, the magnitude of the azimuthal Fourier terms is assessed. For many natural rocks the harmonic equations describing effective HTI anisotropy can be simplified, allowing for faster and more cost effective estimation of the magnitude and orientation of the anisotropy. Limits to these approximations in terms of the number of input azimuthal sectors used in the estimations are discussed.