A Laplacian Filtering Method for Suppressing Noise in Reverse Time Migration Imaging

Abstract

The invention discloses a Laplace filtering method for suppressing reverse time migration imaging noises. The Laplace filtering method comprises performing frequency compensation processing on seismic data and a source function so as to acquire the seismic data of frequency compensation and the source function of the frequency compensation; processing a wave field function, and performing reverse time migration processing to acquire a migration wave field or migration imaging, based on the processed wave field function, the seismic data of frequency compensation and the source function of the frequency compensation; performing Laplace filtering processing on the migration wave field or the migration imaging; and performing amplitude compensation for the migration wave field or the migration imaging after Laplace filtering processing so as to obtain a final imaging result. The Laplace filtering method for suppressing reverse time migration imaging noises can effectively remove the low frequency noise for the reverse time migration imaging, and can improve the phase of a seismic event and the frequency fidelity degree during the noise removing process. The Laplace filtering method for suppressing reverse time migration imaging noises has no need for modifying the condition for reverse time migration imaging and does not increase the calculated amount of the algorithm, so that simplicity and high efficiency of the Laplace filtering method are guaranteed.

Description

technical field [0001] The invention relates to the technical field of seismic physical exploration, in particular to a method for seismic data reverse time migration imaging processing. Background technique [0002] Reverse time migration is currently the most accurate seismic migration imaging technique. However, low-frequency noise will be brought about when the reverse time migration technique is used for imaging processing, and this noise has a serious impact on the imaging quality. At present, an important means to remove this noise is to use the Laplacian filter method. The Laplace filtering method has a fairly good filtering effect, but due to the algorithm itself, the phase and amplitude of the effective seismic event will change, which will lead to distortion of the imaging results and ultimately affect the imaging accuracy. [0003] For the above-mentioned distortion, the distortion is mostly ignored when using the Laplace filtering method. Neglecting this dist...

AI Technical Summary

Problems solved by technology

In the imaging process, it is also necessary to calculate the Poynting vector or the calculation of the reflection angle, which increases the amount of calculation of the migration itself, and the application is not flexible and efficient.

[0005] The above two methods of eliminating imaging noise are too expensive to calculate, and are not as convenient and fast as the Laplacian filtering method. Therefore, a fidelity Laplacian filtering method is urgently needed to suppress the imaging noise of reverse time migration.

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