Publications

Many reservoirs have been discovered and developed with conventional seismic surveys that use compressional, or P waves, to map the subsurface. However there are many instances where P waves do not adequately image the reservoir such as where the presence of shallow gas disrupts P wave propagation or where sands with low impedance contrast, that are invisible to P waves, are present.One solution is to record shear waves, or S waves, in addition to P waves. Marine multicomponent seismic emerged as a revolutionary concept 7 years ago and was championed in the North Sea for a multitude of applications. Since then over 150 surveys have been acquired, processed and some even interpreted. In addition to improving the seismic image additional benefits of multicomponent seismic can include the measurement of azimuthal anisotropy, eliminating strong water bottom multiples and provide lithology and fluid discrimination. Most surveys have been 2D but recent appreciation of the technique has led to large 1000sq km 3D surveys in the Gulf of Mexico and very focused high-resolution 3D surveys in the North Sea. Although the cost of 3D multicomponent is 2 to 20 (twenty) times that of streamer data the emerging commercial viability of this seismic method is driving development of acquisition, processing and interpretation tools and methodologies.Differences in the symmetry of P wave and S wave travel paths require careful survey acquisition geometry design to ensure adequate coverage. Wave mode specific algorithms are used to process the data. Similarly different acquisition geometries require specific processing routines.Azimuthal anisotropy has gained acceptance in exploration and exploitation today. Recent advances in data quality and processing tools to handle anisotropy have made this an enabling technology rather than limiting image resolution.