Thin bed identification method of seismic prospecting

Abstract

The invention discloses a thin bed identification method of seismic prospecting, and belongs to the field of oil-gas geophysical prospecting engineering. The method comprises the following steps that (1) Hilbert transform is carried out on a seismic post-stack signal to obtain an instant phase of the seismic post-stack signal; (2) a time-phase relation diagram of the seismic post-stack signal is obtained according to the instant phase; (3) wavelet transform is carried out on the basis of the time-phase relation diagram of the seismic post-stack signal to obtain a time-scale relation diagram; (4) an abnormal point is extracted on the basis of the time-scale relation diagram; and (5) information of a reflected wave signal is obtained on the basis of the abnormal point. According to the method provided by the invention, seismic phase data can be re-explained by utilizing Hilbert transform on the basis of a phase criterion, further a position identification research can be carried out, the thin bed identification capability can be improved effectively, and interference of aftershock in a result can be eliminated to certain extent.

Description

technical field [0001] The invention relates to the field of oil and gas geophysical prospecting engineering, in particular to a method for identifying thin layers in seismic exploration. Background technique [0002] Seismic data interpretation is to convert seismic information into geological information. The core is to apply seismic exploration principles and basic geological theories based on the reflection characteristics of seismic sections and seismic information, and endow it with clear geological meaning and conceptual model. At present, in seismic data processing and interpretation, there is a better display method for thicker reservoirs. Generally, synthetic records can be made based on seismic reflection signals and logging curves, and thicker formations can be clearly displayed. [0003] In seismic exploration, the concept of thin bed is relative. Because the definition of a thin layer in seismic exploration is based on its vertical resolution, that is, for sei...

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Problems solved by technology

[0005] In the original seismic section, due to the influence of factors such as seismic frequency and signal absorption and attenuation, it is difficult to identify thin layer signals, and traditional analysis methods often have strong limitations in the ability to identify thin layers

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