Seismic data static correction method and system

Abstract

The invention discloses a seismic data static correction method and system. The seismic data static correction method includes the steps that the first arrival time is obtained according to seismic data of an experiment area, refraction layering is carried out in a CMP gather of the experiment area, and the refraction speed and the delay time of each shot point or each receiver are obtained through calculation; an initial model of the experiment area is built, and an underground speed space model is obtained according to first arrival time tomography inversion; certain part of shot points or receivers are selected for micro-logging investigation, high-speed layer burial depth data of the certain part of shot points or receivers are obtained, depth calibration is carried out on the underground speed space model, and the corresponding tomography inversion stratum speed is obtained; the space interpolation is carried out on other shot points or receivers, the corresponding tomography inversion stratum speeds of the shot points or receivers at the high-speed layer burial depth positions are obtained, and high-speed layer burial depth data of the shot points or receivers are extracted point by point; the static correction amount of the shot points or receivers are calculated, and static correction is carried out on seismic data through the static correction amount.

Description

technical field [0001] The invention relates to the field of geophysical exploration, and relates to a static correction method and system for seismic data. Background technique [0002] Static correction is a correction made to seismic data, which is used to compensate for the effects of elevation, weathered layer thickness and weathered layer velocity, and correct the data to a specified datum. Its purpose is usually to obtain the arrival time of reflected waves when collecting on a plane and there is no regolith or low-velocity medium. In seismic exploration areas, it is generally necessary to carry out surface surveys to obtain geophysical parameters related to the surface, directly use control point interpolation or use first-arrival information of cannons combined with surface survey information to invert to establish a surface model, and use the surface model to calculate the base level. Correction is a main data processing method in seismic exploration to eliminate ...

AI Technical Summary

Problems solved by technology

[0006] For the static correction problem in the above-mentioned seismic data processing, the present invention aims at areas with extremely thick low-velocity zones and complex and changeable surface structures. The delay time and refraction velocity data obtained by the refraction inversion method, and the space velocity distribution data obtained by the tomographic inversion method combine the advantages of these three methods to establish a surface model through the method of depth calibration, and propose a seismic The data static correction method and system are used for static correction processing of seismic data, thereby overcoming the low accuracy of the surface model in complex areas in seismic exploration, the possible risks of medium and long wavelength static correction, and the difficulty and existence of model description. Larger errors and other issues

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