Method for suppressing interference of seismic data multiples on land

Abstract

The invention discloses a method for suppressing interference of seismic data multiples on the land. Arranging and zone dividing are conducted on a preprocessed seismic data set according to the CMP and the offset, a section is obtained according to image speed stacking and the offset, the range of a single advantage zone is determined in the area outside a multiple advantage zone, time windows with the same length are selected on a strong reflection layer time section and a multiple occurring time section which generate the multiples, cross correlation is conducted on the time windows, the amplitude value of each zero phase is calculated, weighting is conducted according to the amplitude values, and suppressing of the interference of the seismic data multiples on the land is achieved. Time orientation differentiation is conducted, and suppressing of the interference of the seismic data multiples on the land is achieved. The method lowers the requirement for the speed precision and the multiple and single fluctuation correction time difference threshold of a common method for suppressing multiples in a domain transformation mode at present and has the higher practical operability and the higher application success rate.

Description

technical field [0001] The invention relates to a data processing technology for petroleum seismic exploration, and is a method for suppressing multiple wave interference of onshore seismic data. technical background [0002] Seismic exploration is the main method for finding and exploring for oil and gas. The main work includes three steps of seismic data acquisition, processing and interpretation. Seismic data processing mainly provides data results for seismic data interpretation. There are many seismic data processing contents, including denoising, deconvolution, dynamic and static correction, velocity analysis, stacking, migration and inversion. In order to improve the signal-to-noise ratio, denoising has become an essential task in seismic data processing. Seismic data contains a lot of noise, and multiple interference is one of them. Suppressing multiples has become an important processing technology in data processing. Onshore data processing to suppress multiples...

AI Technical Summary

Problems solved by technology

However, for multiple waves with complex causes, especially for land seismic data, the strong reflection layers that generate multiple waves are affected by changes in the physical properties of the overlying strata (velocity, surface conditions, surface consistency, lithology, wave characteristics, etc.), The speed changes accordingly in space. The uncertainty of the speed, as well as the influence of various interlayer multiples and mixed multiples at the same time, lead to the characteristics of the multiple waves generated by it and the primary wave mixing. Stacked together, it is still difficult to find a clear boundary in the velocity and time domain, which affects the signal-to-noise separation effect, and often suppresses multiple waves at the same time, causing serious loss of effective waves, especially for weak reflection signals with very low signal-to-noise ratio damage Seriously, this kind of damage will directly affect the success or failure of suppressing multiple waves, which is also an important reason why it is difficult to achieve ideal results in the current method of suppressing multiple waves with land seismic data

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