High accuracy depth domain prestack earthquake data inversion method

Abstract

The invention relates to a pre stack seismic data inversion method of globe physical exploration high accuracy depth domain, which has the following steps: single shot records are collected; according to pre stack shot gather data and through radial line track or wave-field continuation focus, wave-field continuation focusing operators of all detecting wave points are pointed to and the focusing operator of each imaging point is obtained; the focusing operator and the single shot record are implemented in a migration aperture, and focus point shot gather corresponding to each shot is obtained; the focusing operator and common focus point gather are implemented cross correlation operation in time domain and space domain at the same time, and net point gather is obtained; the net point gather is implemented Radon transform, and CFP-AVP gather of corresponding imaging point is obtained; each imaging point gather is stacked, and the whole 2D document pre stack high accuracy analysis sectional plane is obtained. The CFP-AVP analysis in the invention has the advantages of wide application condition, reliable analysis sectional plane and sound effect of supercritical information inversion.

Description

technical field [0001] The invention relates to geophysical exploration technology, in particular to a high-precision depth-domain pre-stack seismic data inversion method under the premise of not reducing imaging quality in reflection wave seismic exploration. Background technique [0002] In reflection wave seismic exploration, the reflection information (seismic record) from underground geological bodies is obtained by exciting the ground explosive source, vibrator or heavy hammer source. For these reflection information, a series of seismic data processing is required. Including static correction, dynamic correction, stacking and migration, etc., and then obtain the imaging section for geological interpretation, including stacking section and migration section, stacking velocity field and layer velocity field, etc., which are predicted by the joint interpretation of geological personnel Where there may be oil and gas. However, the stacking and migration profiles are the ...

AI Technical Summary

Problems solved by technology

First of all, the NMO processing in conventional processing tends to distort the waveform of the event (mainly waveform deformation), and the distortion of the event at a far offset is also the most serious

Therefore, waveform distortion becomes the biggest problem in conventional AVO inversion

Secondly, NMO processing will also move the processed waveform to low frequency (mainly caused by waveform stretching), and in areas with relatively complex structures, such as faults, unconformities and annihilators, the amplitude of reflected waves will be seriously affected. distortion, the resulting AVO inversion results are not very reliable

Furthermore, since the event of the reflected wave is not completely homing after NMO processing, and the diffracted wave does not converge completely (this is an inevitable defect in conventional processing), the result of its AVO inversion is biased

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