Anisotropy parameter inversion method based on basis pursuit transverse multi-channel constraints

Abstract

The invention discloses an anisotropy parameter inversion method based on basis pursuit transverse multi-channel constraints. The method comprises the following steps that: seismic data are processed,so that an azimuth angle superposition gather can be obtained; a rock physical model is constructed, so that crack parameter logging data can be obtained; decorrelation processing is performed on thelogging data; an inversion objective function is constructed; and a to-be-inverted parameter reflection coefficient sequence is obtained based on the inversion objective function. According to the anisotropy parameter inversion method based on the basis pursuit transverse multi-channel constraints, azimuth angles are introduced, so that the azimuth angle superposition gather can be obtained; theazimuth angle superposition gather has a high channel ratio and includes multiple seismic information, and therefore, crack information in a reservoir can be provided accurately; the logging data is subjected to the decorrelation processing, so that the accuracy of the inversion result is improved; and related constraint items are added into an objective target function, the inversion target function can be constructed, and therefore, the stability and transverse continuity of the inversion result are improved, and the uncertainty of the estimation of unknown parameters is reduced.

Description

technical field [0001] The invention belongs to the field of geophysical inversion, and in particular relates to an anisotropic parameter inversion method based on basis tracing transverse multi-track constraints. Background technique [0002] As exploration targets shift to complex oil and gas reservoirs, unconventional oil and gas exploration and development has become a research focus. In the exploration of shale gas, it is very important to effectively identify the degree of fracture development, and fractured reservoirs have anisotropic characteristics. is of great significance. [0003] With the rapid development of wide-azimuth seismic data acquisition and processing technology, the use of wide-azimuth pre-stack seismic data to predict subsurface fractures has become a major research method. At present, the anisotropic parameter inversion method based on azimuthal prestack seismic data mainly uses the variation of reflection coefficient with incident angle and azimu...

AI Technical Summary

Problems solved by technology

At present, the anisotropic parameter inversion method based on azimuthal prestack seismic data mainly uses the variation of reflection coefficient with incident angle and azimuth angle during the propagation of seismic waves in fractured reservoirs to study, and the theoretical derivation mainly comes from Ruger in 1998 The approximate formula of the reflection coefficient based on the equivalent transverse isotropic medium was proposed in 1999. Afterwards, some relevant scholars made a series of simplifications to the equation, but there are still problems of reliability and stability in the inversion of anisotropic parameters.

In addition, the anisotropic characteristics of fractured reservoirs affect the amplitude of seismic waves, resulting in lateral discontinuity in the inversion process.

Images