Method and system for separating three-dimensional three-component vector wave field

Abstract

The invention discloses a method for separating a three-dimensional three-component vector wave field. The method comprises the following steps of: establishing an orthorhombic O-Z-R-T three-dimensional coordinate system; detecting wave vector directions of a vertical wave, a fast transverse wave and a slow transverse wave; establishing a first affine coordinate system according to the wave vector direction of a projection vector of the vertical wave on an incidence face, and the wave vector direction of the fast transverse wave; rotatably converting vectors Z and R of a receiving coordinate system in the first affine coordinate system, so as to obtain a projection vector of the vertical wave on an R-O-Z plane, and the quick transverse wave; and rotatably converting the projection vector of the vertical wave on the R-O-Z plane and a polarization projection vector on a T axis in a second affine coordinate system, so as to obtain the vertical wave and the slow transverse wave. The method and the device provided by the invention can separate the vector wave fields of the vertical wave P, the fast transverse wave SV and the slow transverse wave SH.

Description

technical field [0001] The invention belongs to the field of seismic data analysis, and in particular relates to a method and system for separating three-dimensional and three-component vector wave fields. Background technique [0002] In three-dimensional three-component vector (3 DIMENSION 3 COMPONENT, 3D3C) seismic exploration, geophones are usually required to receive seismic waves from underground media, including longitudinal waves P and shear waves S. In the O-Z-R-T three-dimensional orthogonal coordinate system defined by it, the longitudinal wave P whose Z component is the vertical component, the R component and the T component receive the shear wave S as the horizontal component, that is, a shear wave rotation transformation in the shear wave S along the X or Y horizontal direction To the R component pointing to the source-receiver azimuth, another shear wave is transformed into the T component orthogonal to the source-receiver azimuth. This process can be called R...

AI Technical Summary

Problems solved by technology

[0007] 2. The shear wave S is not completely received by the R component

For ground three-component seismic exploration data, this patent proposes a method and technical route for affine coordinate transformation and wave field separation. Efficiently restore the full-amplitude properties of wavefields

[0013] The patent (publication number CN101251603A) can only process two components, ignoring the three-component characteristics of the actual collected data; in the process of continuous velocity analysis and extraction, the speed ratio model will destroy the effect of the method; this method damages the three The vector feature of the component seismic signal has poor amplitude preservation, which is not conducive to subsequent interpretation and inversion

In addition, in areas with severe wave pattern leakage, or areas with complex surface signal-to-noise ratios, especially areas with low shallow layers and thin velocity-slow zones, this technology cannot achieve complete wave field separation.

[0014] The above methods can achieve wave field separation to a certain extent, and obtain seismic wave data after suppressing noise, but because they cannot achieve complete wave field separation, the accuracy of seismic data analysis is insufficient.

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