Prestack depth reverse time migration imaging method and system of absorption attenuation medium

Abstract

The invention provides a prestack depth reverse time migration imaging method of an absorption attenuation medium. The method comprises the steps of: step 1: giving initial values of L strain fittingparameters T sigma 1 within an effective frequency band range of seismic data; step 2: calculating an integral function value at the current calculation frequency based on the initial values of the Lstrain fitting parameters T sigma 1; step 3: obtaining a stress fitting parameter T corresponding to a current Q value according to a fitting parameter expression; step 4: in view of all Q value points in a Q value field data, repeating the step 1 to the step 3 to obtain a fitting parameter data body; step 5: obtaining a sticky acoustic medium wave field forward propagation operator and a sticky acoustic medium wave field reverse propagation operator, and performing forward modelling of a wave field according to the forward propagation operator and the reverse propagation operator to obtain ashot point forward propagation wave field and a detection point reverse propagation wave field; and step 6: performing imaging by using imaging conditions for the shot point forward propagation wave field and the detection point reverse propagation wave field of any moment. By adopting the prestack depth reverse time migration imaging method provided by the invention, the efficiency of prestack depth reverse time migration imaging is greatly improved under the condition of ensuring the imaging accuracy.

Description

technical field [0001] The invention relates to the technical field of seismic wave field migration imaging, in particular to a pre-stack depth reverse time migration imaging method and system for an absorbing attenuation medium. Background technique [0002] When seismic waves propagate in the underground medium, the incomplete elasticity of the medium will cause absorption and attenuation of the seismic wave field. The inherent absorption characteristics of the medium itself are usually described by the quality factor, which is closely related to the internal structural characteristics of the medium and factors such as saturation, porosity, and permeability. Utilizing formation absorption properties can be used to predict lithology, distribution of sand and mudstone, and under favorable conditions, it can also be directly used to predict the existence of oil and natural gas. Therefore, the analysis and research on the absorption characteristics of seismic waves is of grea...

AI Technical Summary

Problems solved by technology

[0005] Since the Q value is a function of frequency, the traditional Q-RTM is generally implemented in the frequency domain, which is characterized by easy solution and high precision. However, the high-dimensional Fourier transform makes the calculation efficiency of this method very low and cannot be performed large scale application

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