T-f-k field polarization filtering method for multi-component seismic data

Abstract

The invention discloses a t-f-k field polarization filtering method for multi-component seismic data. The method comprises the steps of inputting multi-component seismic shot-gather data; acquiring the vertical component and the radial component of the multi-component seismic shot-gather data; generating complex-vector shot-gather seismic data with the vertical component as an imaginary part and the radial component as a real part; setting a time window length, an elliptical polarizability filtering threshold and a frequency threshold; converting the t-f-k transformation on the complex-vector shot-gather seismic data to obtain a three-dimensional time-varying frequency wave spectrum; according to the positive and negative frequencies of the three-dimensional time-varying frequency wave spectrum, acquiring an elliptical polarizability; according to the elliptical polarizability, the elliptical polarizability filtering threshold and the frequency threshold, acquiring a filtering function; conducting the three-dimensional median filtering on the filtering function; filtering the three-dimensional time-varying frequency wave spectrum based on the filtering function; and conducting the t-f-k transformation on the filtered three-dimensional time-varying frequency wave spectrum. According to the technical scheme of the invention, the problem in the prior art that rayleigh surface waves and transverse waves cannot be effectively separated from each other due to the small difference between the frequencies and the apparent velocities of the rayleigh surface waves and the transverse waves can be solved.

Description

technical field [0001] The invention relates to the technical field of seismic exploration, in particular to a t-f-k domain polarization filtering method for multi-component seismic data. Background technique [0002] In current seismic data processing, surface waves are usually regarded as strong regular interference waves, and suppressing them is a necessary step to improve the signal-to-noise ratio and resolution of seismic data. For single-component P-wave data, surface waves and reflected P-waves are quite different in frequency and apparent velocity, and surface waves are easier to suppress. However, for the current multi-wave and multi-component seismic exploration technology for complex unconventional oil and gas reservoirs such as lithologic reservoirs, fractured and fractured reservoirs, coalbed methane and shale gas, the effective waves of the horizontal components in the multi-components are mainly converted shear waves. The inherent properties of converted shea...

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Problems solved by technology

[0006] The main purpose of the present invention is to provide a t-f-k domain polarization filtering method for multi-component seismic data, to solve the problem in the prior art that it is difficult to effectively separate the Rayleigh surface due to the small difference in frequency and apparent velocity between the shear wave and the Rayleigh surface wave wave vs. shear wave problem

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