Multi-component converted wave static correction method by using surface waves

Abstract

The invention relates to a multi-component converted wave static correction method by using surface waves, which comprises a step of solving stratigraphic classification and transverse wave velocity of a superficial layer through the extraction of the surface waves and the inversion of frequency dispersion curves based on Rayleigh surface waves in a shot record, so as to accurately calculate static correction quantity of detection points of converted waves. The test processing on two-dimensional three-component of a certain block in Daqing shows that a transverse velocity non-uniform body of the superficial layer generates a larger static correction time difference; and the processing on three-dimensional three-component data of a certain coal mine in Huainan shows that the static correction time difference of over 20 milliseconds can also occur due to the low and transversely non-uniform transverse wave velocity even in a flat plain terrain, and for a coalfield high-resolution seismic exploration to recognize minor faults of about 3 meters, the static correction time difference is a non-ignorable error. Application tests in three-component seismic data processing in two regions achieve a better processing effect and prove that the multi-component converted wave static correction method by using the surface waves is a feasible method.

Description

technical field [0001] The invention relates to the field of engineering geophysical prospecting, in particular to a surface wave multi-component converted wave static correction method. Background technique [0002] Due to the undulations of the terrain or the presence of horizontal velocity inhomogeneities in the shallow layer, the reflected seismic signals reaching the surface will not only have the normal time difference caused by the normal offset and depth changes on different geophones, but also appear due to the surface The change of travel time caused by the abnormality of the shallow low and deceleration zone. This change in travel time must be eliminated in the processing of the reflected wave signal in order to obtain normal imaging of the subsurface medium. The correction of this time difference is called static correction in the field of artificial seismic signal processing. [0003] Static correction is generally divided into two categories. One method is to...

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Problems solved by technology

[0023] The technical problem to be solved by the present invention is to extract the surface wave interference for the multi-component seismic data in the area where the land surface wave develops, and invert the shear wave velocity structure through the dispersion curve of the surface wave to achieve the conversion of the static correction of the shear wave; Increase investment in field acquisition and solve the problem of static correction of converted waves without relying on shear wave refraction first-arrival pickup

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