Frequency domain full-waveform inversion seismic velocity modeling method

Abstract

The invention relates to a frequency domain full-waveform inversion seismic velocity modeling method. The method comprises the following steps of: 1) acquiring an original seismic shot gather record, focus wavelet information and an initial model used by inversion; 2) analyzing information acquired in the step 1), and determining basic inversion parameters and a full-waveform inversion frame from low frequency to high frequency based on a forward modeling algorithm and an optimization algorithm; 3) calculating to acquire the most appropriate forward and inversion model network for different frequencies; 4) compressing data dimensions which participate in inversion by a principal component analysis method during low-frequency inversion; 5) judging whether projection matrix dimensions corresponding to different frequencies meet the threshold value conversion standard, if the conversion standard is met, performing a next step, and if the conversion standard is not met, returning to the step 4); 6) introducing a focus encoding method, and pressing crosstalk noise by a random phase encoding method; 7) judging whether an iteration stopping condition is met, if the iteration stopping condition is met, performing a next step, and if the iteration stopping condition is not met, returning to the step 6); and 8) if the inversion of all the frequencies is not finished, returning to the step 3) until the inversion of all the frequencies is finished, acquiring the final velocity model, and outputting the velocity model.

Description

technical field [0001] The invention relates to a modeling method, in particular to a seismic velocity modeling method of full waveform inversion in the frequency domain. Background technique [0002] Since the realization of full waveform inversion is a process of multiple iterative optimization, a large number of wave field forward simulation operations based on the wave equation are required. Therefore, the excessive calculation cost is an important factor restricting the application and development of this method. How to compress the calculation Cost and improving algorithm efficiency have always been the frontier topics of research on full waveform inversion at home and abroad. There are two main ways to improve the calculation efficiency of full waveform inversion, one is the high-efficiency optimization algorithm, and the other is the compression of the original data. Among them, although the use of an optimization algorithm with a faster convergence speed can reduce...

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Problems solved by technology

However, this method is greatly affected by crosstalk noise, and the resolution of the inversion result is insufficient. In addition, this method is also greatly affected by environmental noise.

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