Multi-domain frequency-division parallel multi-scale full-waveform inversion method

Abstract

The invention relates to a multi-domain frequency-division parallel multi-scale full-waveform inversion method. A smooth initial model is established by using time-domain empirical mode decomposition full-waveform inversion; a high-precision initial model is established by using frequency-division parallel Laplace-Fourier-domain full-waveform inversion; and then an underground high-precision speed model is established again by using frequency-division parallel frequency-domain multi-scale full-waveform inversion. During the whole process, a dynamic random coding strategy is employed, so that the inversion rate is accelerated and the crosstalk noises inside a super gun can be suppressed. According to the invention, multi-domain combined inversion, frequency-division parallel and dynamic random focus coding strategies are used during the underground speed inversion process. Under the circumstances of low frequency deficiency and poor initial models, the smooth initial model is established by using time-domain empirical mode decomposition full-waveform inversion, so that the full-waveform inversion cycle skipping phenomenon is avoided. And during the inversion process, the master-slave parallel calculation method is used, so that the calculation efficiency of full-waveform inversion is improved substantially and the inversion precision is enhanced.

Description

technical field [0001] The invention relates to an underground imaging for seismic exploration, in particular to a frequency division parallel and multi-domain multi-scale inversion method, and uses a dynamic random source coding strategy to perform full waveform inversion. Background technique: [0002] With the development of petroleum industry and the deepening of exploration and development, the exploration difficulty gradually increases from the stage of structural exploration to the stage of lithologic exploration. To meet this requirement, full waveform inversion has developed rapidly and has become a research hotspot in today's geophysical field. In the 1980s, Tarantola proposed the time-domain full-waveform inversion method, and obtained the derivation of the model parameters of the objective function through the cross-correlation operation of the residual inverse wavefield and the normal wavefield, thus avoiding the need to obtain the Jacobi matrix. In the 1990s, ...

AI Technical Summary

Problems solved by technology

When the current frequency information is found to be unreliable, then change to a slightly higher frequency to perform full waveform inversion in the Laplace-Fourier domain. In this way, it may waste a lot of time to find the most reliable frequency information in the process of trying to calculate different frequencies.

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