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Azimuthal inversion is state-of-the-art inversion technology for stress and fractured reservoir characterization and detection in anisotropic media. This technology requires a wide-azimuth seismic survey and careful azimuth dependent processing with noise attenuation. In this paper, the influence of noise attenuation on the reliability of anisotropic inversion results is discussed. The implementation of this technology for the understanding of horizontal stresses and the verification of the results with well data and microseismic will be presented.

The search for hydrocarbons has spanned vast areas of the globe. Despite many successes, entire basins and plays have been deemed unprospective, perhaps prematurely, based on single well results, or poor-quality seismic data. The advent of broadband seismic acquisition, combined with new deghosting/imaging algorithms and exponential increases in computer processing power, has generated improved seismic images. These advances give scientists an opportunity to re-evaluate a region’s subsurface geology. The new interpretation, combined with geology-based datasets, is now being studied in conjunction with modern and historical seismic data, to fully understand petroleum prospectivity.

We demonstrate a 4D FWI technique using a synthetic study involving 3D elastic modeling through a highly realistic Earth model akin to the actual Grane PRM data. For this acquisition configuration, this study also indicates there is minimal sensitivity of the method to various residual uncertainties in the data and the modeling. 4D FWI results using the real time-lapse Grane PRM data with a six month acquisition interval between vintages shows changes at the reservoir level that correlate with both injecting and producing wells. In addition, we find good agreement comparing the velocity differences from 4D FWI to 4D time-shifts from the fully processed and imaged seismic data.

This paper reviews elastic property changes in anisotropic mediums and proposes a workflow to model elastic stiffness tensor using conventional well logs in a vertical transverse isotropic medium. The proposed workflow uses the concept of downscaling and then upscaling of normal logs using Backus model and rock physics modeling which couples different effective medium theories together. The choice of the rock physics model depends on the anisotropy source in the given medium. Rock physics modeling is the main step in this workflow, and is very important in defining the final elastic constants of the medium. It is the place where all anisotropy information is integrated with the log information. Finally, this workflow is tested on the Duvernay shale formation in the western Canadian sedimentary basin where log data along with the laboratory core measurements are available. The good match between modeled and measured velocity confirms the validity of this workflow.

The Northern Viking Graben seismic dataset was acquired using CGG’s BroadSeis™/BroadSource™ true broadband solution, which combines a multi-level source and curved variable-depth streamer technology with advanced and customized imaging technologies. The dataset covers more than 35,000 km2, spanning both the Norwegian and UK North Sea. The high-resolution seismic imaging is a key component of the ongoing integrated studies, which will enhance subsurface knowledge and assist with the identification of prospects and new play models.

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.