AVD - An emerging new marine technology for reservoir characterization: Acquisition and application

Several significant developments in marine technologies in the past few years have resulted in the creation of acquisition techniques suited to azimuthal anisotropy analysis in the offshore environment. The developments have parallelled the evolution in the theory underlying the use of P-P and P-S amplitude versus direction (AVD) for seismic anisotropy estimation. The demands of such AVD methods for a wide azimuthal coverage have only recently been met. To guide future work, the AVD method has been assessed using data from intersecting streamer lines. Application of the method in this example permits an identification of the strike direction of hydrocarbon-filled fractures within a chalk formation in the central North Sea. The results of this study provide confidence that the method is sufficiently sensitive to fractures and can help guide future analyses. The new generation of vertical cables, seabed seismic sensors, and walk-away (and/or 3-D) vertical seismic profiles will eventually lead to high-resolution anisotropy estimation in the offshore environment using this approach. © 1999 Society of Exploration Geophysicists.