Extraction method and extraction device for extracting converted wave angle gather of transversely isotropic media

Abstract

The invention provides an extraction method and an extraction device for extracting the converted wave angle gather of transversely isotropic media. The method comprises the steps of based on a co-conversion point gather of pre-stack converted waves, obtaining a converted-wave stacking velocity Vc2, a vertical velocity ratio gamma 0, an equivalent speed ratio gamma eff and a converted wave anisotropic parameter Chi eff through the velocity analysis progress; at a k-th sampling point, processing each seismic trace in the co-conversion point gather to obtain an incident angle theta k at the k-th layer of the pre-stack converted waves; assigning k to be 1 to n, and conducting the above treatment for each k value so as to obtain a converted-wave incident angle of each seismic trace at each sampling point; classifying seismic traces of the same converted-wave incident angle into the same incident angle gather so as to obtain a converted wave angle gather, wherein n represents the number of total sampling points.

Description

technical field [0001] The present disclosure relates to the field of seismic exploration data processing, and more specifically, to a method and device for extracting converted wave angle gathers from transversely isotropic media. Background technique [0002] On the prestack converted wave co-conversion point gather, the converted wave amplitude varies with the offset (AVO). The pre-stack angle domain AVO inversion can obtain the compressional wave velocity, shear wave velocity, density, etc. of the reservoir, and is an important technology for reservoir elastic parameter inversion, reservoir prediction and fluid prediction. The conversion from offset to angle is the key technology of prestack angle domain AVO inversion. Each seismic trace has a fixed offset, and sampling points at different times on the trace have different reflection angles. In order to obtain the information of the variation of the reflected wave amplitude with the incident angle, it is necessary to t...

AI Technical Summary

Problems solved by technology

This algorithm has the advantages of high precision, the speed is between the straight ray and curved ray methods, but in the conversion process, the stability is poor, it is easy to introduce errors, and the calculation accuracy is affected by the equivalent offset of the longitudinal wave and the anomalous parameters of the longitudinal wave Constraints on Conversion Accuracy and Computational Accuracy of Post-mapped P-wave Traveltime

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