Intensity of Scattered Waves: A New Seismic Criterion for Predicting Filtration-Capacity Properties of an Oil-Saturated Reservoir

摘要

1. The oil fields of eastern Siberia are usually confined to certain local heterogeneities of the lithologi-cal replacement type, as opposed to classical structures. Such zones are generally characterized by a high degree of fracturing. Therefore, they produce not only reflected waves, but also sufficiently intense scattered wave fields in seismic records. The seismic wave field in such zones can be presented as a superimposi-tion of reflected and scattered/diffracted waves. It is natural that both types of the wave field should be studied in order to scrutinize the reservoir structure, because the two wave fields characterize different properties of the reservoir: reflected waves are responsible for its correct positioning in space, while scattered/diffracted waves specify its internal structure. Thus, an adaptive procedure for the construction of seismic wave records is needed for the full description of the reservoir. It should provide for the possibility of constructing images both as regular boundaries, which generate intense reflected waves, and as singular seismogeological objects (points of sharp turns and breaks of boundaries, separate scattering objects and their clusters, and so on), which generate intense scattered waves. It should be noted that the amplitude of regular reflected waves is always significantly higher than that of scattered waves. Therefore, reliable images of singular objects cannot be constructed without the suppression of the regular component of the wave field. Such a procedure of focusing transformation was based on ideas of Yu.A. Tarasov, substantiated, and tested on synthetic and real profiles of the multifold overlap. Its modified version was applied to the study of an areal system of profiles.