Method for analyzing impulse noise interference in vibroseis earthquake records

Abstract

The invention relates to a method for analyzing impulse noise interference in vibroseis earthquake records. The method comprises the steps that first, a reference amplitude value and a noise detection threshold value are determined by direct wave signals of a vibroseis according to the working principle of the vibroseis; then, the algorithm of impulse noise in an automatic detection record is designed according to the detection threshold value; at last, the impulse noise obtained by detection is analyzed, and the degree that a vibroseis record is influenced by the impulse noise is evaluated. The method for analyzing the impulse noise interference in the vibroseis earthquake records can be widely adaptive to the linear or nolinear frequency sweep mode of the vibroseis, noise analysis of the collecting process of vibroseis earthquake exploration data in an earthquake data collecting site can be quickly and effectively achieved, the influence of the impulse noise of the vibroseis on the records is analyzed in real time, the condition that a relevant record of the vibroseis is bad in quality caused by a strong noise level or random strong impulse noise is avoided, therefore, cost is lowered, the collecting quality of the vibroseis is effectively guaranteed.

Description

Technical field: [0001] The invention relates to a noise interference analysis technique in geophysical data, in particular to an analysis method for the interference of pulse noise in a vibrator seismic record to a vibrator seismic record. Background technique: [0002] Impulse noise refers to short-duration and large-amplitude noise in seismic records. In actual seismic exploration, due to external random factors, a large amount of impulsive noise will be generated, and the interference of these impulsive noises on shock sources such as explosive sources is slight, but the interference on related records of vibroseis is serious. Due to the different working principles of the vibrator and the shock source, when extracting seismic signals similar to the shock source from the seismic record of the vibrator, it is necessary to carry out relevant detection on the original seismic record of the vibrator, and the impulse noise mixed in the original record is also passed through ...

AI Technical Summary

Problems solved by technology

Due to the different working principles of the vibrator and the shock source, when extracting seismic signals similar to the shock source from the seismic record of the vibrator, it is necessary to carry out relevant detection on the original seismic record of the vibrator, and the impulse noise mixed in the original record is also passed through After the correlation detection process, since the correlation algorithm is a nonlinear operation, the impulse noise mixed in the original record has undergone a nonlinear change, so that the interference to the signal is no longer local, resulting in a significant continuous noise level. Elevated, severely degrading the quality of vibrator seismic records

[0003] In the actual vibroseis seismic exploration, if the seismic data after correlation is directly recorded, the interference caused by the impulse noise before correlation will be difficult to remove in the correlation record, and it will be difficult to suppress even in the subsequent data processing; if the subsequent seismic data During the processing, if it is found that the noise in the related records of the vibrator is too strong, it can only be returned to the field for data acquisition again, resulting in a significant increase in acquisition costs

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