Harmonic noise suppression method based on waveform morphology sparse modeling

Abstract

The invention discloses a harmonic noise suppression method based on waveform morphology sparse modeling. The harmonic noise suppression method includes the steps of 1) constructing Chirplet transform according to waveform morphological characteristics of harmonic noise in seismic records acquired via vibroseis slip sweep, and constituting an over-complete dictionary with continuous wavelet transform; 2) quickly implementing Chirplet positive and inverse transforms; 3) determining Chirplet transform parameters based on time-frequency distribution characteristics of correlated data; and 4) according to the starting frequency of a reference scanning signal, determining the filter cutoff frequency of the harmonic noise to achieve fidelity separation of an effective signal from the harmonic noise. The invention solves the problem of harmonic noise interference in the seismic data acquired via vibroseis slip sweep, and achieves the purpose of improving the signal-to-noise ratio of the seismic data. The method of the invention determines the Chirplet transform according to the time-frequency distribution characteristics of the harmonic noise, and ensures the sparseness; the fast implementation of the Chirplet transform guarantees the efficiency of transform, and the correction coefficient guarantees the accuracy of inverse transform reconstruction; and the Chirplet transform parameters are automatically determined according to the data drive, a strong adaptability is gained and single-channel calculation facilitates parallel processing.

Description

technical field [0001] The invention belongs to the technical field of data processing in seismic exploration, in particular to a method for suppressing harmonic noise in seismic acquisition data. Background technique [0002] With the rapid development of the global economy and the improvement of environmental protection awareness, the traditional explosive source is gradually replaced by the vibrator. Sliding scanning is a commonly used acquisition method in vibroseis construction, which improves the acquisition efficiency. However, the sliding scan has the problem that the acquired seismic records are interfered by strong harmonic noise, and the effective signal is often hidden in the harmonic noise, which has a serious impact on the quality of the data. At present, there are the following methods for suppressing harmonic noise: one is the pure phase shift filtering method, but this method deals with seismic records before correlation, the data volume is large and the ca...

AI Technical Summary

Problems solved by technology

However, harmonic noise is relatively complex, and it is necessary to construct a more suitable and matching transformation for sparse representation, and to select specific parameters for the transformation. At present, there are few related studies

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