Elastic wave gaussian beam pre-stack depth migration technology

Abstract

The invention provides an elastic wave gaussian beam pre-stack depth migration technology, which comprises the following steps of: 1) according to a selected gaussian beam primary width, dividing a single slot record into a series of stacked areas by a gaussian window, wherein the center of each area is a beam center; 2) decomposing a multi-component seismic record into different wave-formed local plane wave components by utilizing local slant stack; 3) respectively test-firing the elastic dynamic gaussian beams from hypocenter and beam centers and calculating the travel time and amplitude information of each gaussian beam in an effective range; 4) according to a PP wave and PS wave-deduced imaging formula, calculating an corresponding image value of each beam center by utilizing the travel time, the amplitude information of the gaussian beam, the polar information and surface local inclined information; and 5) repeating the calculations of steps 3) and 4), thereby acquiring an imaging result of the single slot, wherein the final migration result is the stack of all imaging results of the single slot. The method can be used for repeatedly imaging the multiple waves, is higher in precision, has calculation efficiency and flexibility and is a multi-component seismic imaging method having higher application value.

Description

Technical field [0001] The invention belongs to the field of multi-component seismic data processing, and is a depth domain imaging method suitable for multi-wave and multi-component seismic data. Background technique [0002] With the improvement of the level of geophysical prospecting technology and equipment, multi-wave (multi-component) seismic exploration has been paid more and more attention by the industry, and has gradually entered into industrial production. Multi-component seismic technology has shown its unique advantages and great application potential in hydrocarbon prediction of heterogeneous reservoirs, fine description and dynamic monitoring of oil and gas reservoirs. However, the existing imaging methods suitable for multi-component seismic data are not perfect enough, and there is often a contradiction between imaging accuracy and computational efficiency. [0003] In the process of traditional multi-component seismic data processing, the seismic data is o...

AI Technical Summary

Problems solved by technology

The above two types of methods have their own advantages and disadvantages. Although elastic wave reverse time migration has extremely high imaging accuracy, its computational complexity is very large, and its imaging results are often accompanied by a large amount of low-frequency interference and converted wave imaging. The Difficult Polarity Reversal Problem

Although elastic wave Kirchhoff migration is flexible and efficient, it is difficult to image multiple arrivals, resulting in low imaging accuracy for complex underground geological structures

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