This paper describes another possible application of surface seismic data besides its traditional uses. The surface seismic data described herein were acquired as part of a project carried out under a Joint Technology Agreement between a large integrated oilfield services contractor and a major resource holder (MRH). The project aim was to study the benefits of the latest surface seismic technology over the Minagish field in Kuwait. As part of this study, a small 3D pilot surface seismic survey was recorded. The project encompassed surface seismic acquisition, processing and interpretation, rock physics analysis, and borehole seismic technology. A large multi-disciplinary group from the MRH and the contractor was set up to determine the project objectives. These objectives included improved 3D seismic imaging of faults and thin layers, improved determination of reservoir attributes, and to discover if an improved 4D seismic response could be achieved. A set of metrics was put in place to allow measurement of the project success in terms of the required objectives. The key metrics were bandwidth and signal-to-noise ratio. To achieve the project objectives, a significant improvement of prestack bandwidth and signal-to-noise ratio was required.
The focus of this paper is the improvement of imaging and prediction of karst features, such as sinkholes, in Shuaiba formation. This is one unforeseen result obtained during the project-integrated workflow between the contractor and the MRH. Knowledge of location and size of these karst features will allow planning drill locations to avoid sinkholes. This has several positive effects including improved drilling operations by avoiding problems such as loss of drilling fluids, and prevention of problems later in the life of the well. One of the problems caused by placing a well in a sinkhole is accelerated corrosion of the casing string requiring early workover efforts.
A key contributor to the project success was the use of the latest single-sensor recording system and high-fidelity vibrators.