Pre-stack high-angle fast Fourier transform seismic imaging method, system and equipment

Abstract

The invention belongs to the fields of geophysical exploration and seismic imaging, and specifically relates to a pre-stack high-angle fast Fourier transform seismic imaging method, system, and equipment, aiming to solve the problem of high-steep structures being imaged by existing seismic imaging methods. There are problems of imaging quality, low efficiency, and over-dependence on velocity model accuracy. The method includes: acquiring seismic data; extracting a common shot point gather from the seismic data and converting it into a common offset gather, and converting from the space-time domain to the frequency wavenumber domain; calculating the wave propagation angle, and dividing the imaging area into small Angle and large angle areas; solve the constant coefficients of small angle and large angle areas; carry out frequency-divided layer-by-layer wavefield continuation, and obtain imaging results of different frequencies at different depths; integrate the imaging results and convert them to the space domain to obtain Common-offset imaging section: superimpose all common-offset imaging sections to obtain the final imaging result. The invention realizes high-precision seismic imaging of high and steep structures.

Description

technical field [0001] The invention belongs to the fields of geophysical exploration and seismic imaging, and in particular relates to a pre-stack high-angle fast Fourier transform seismic imaging method, system and equipment. Background technique [0002] With the deepening of exploration, extremely complex fault block reservoirs, strike-slip fault reservoirs, fractured buried hills and other oil and gas reservoirs have become new areas that need to be broken through in oil and gas exploration. Strike-slip faults and fractured buried hill structures produce seismic reflections with high angle and weak amplitude. The traditional first-order approximation split-step Fourier transform (SSF) high-efficiency seismic imaging technology based on Born approximation is only suitable for formation imaging with a gentle dip angle (<15 degrees), and can no longer meet the needs of current exploration geological targets. High-precision imaging technologies such as two-way wave-base...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the above-mentioned problems in the prior art, that is, in order to solve the problems of imaging quality, low efficiency and over-reliance on the accuracy of the velocity model in the existing seismic imaging methods when imaging high-steep structures (that is, high-angle strata), this paper In the first aspect of the invention, a pre-stack high-angle fast Fourier transform seismic imaging method is proposed, the method includes the following steps:

Images