Method and system for identifying oil and water in carbonate rocks

Abstract

The embodiment of the invention provides a method and a system for identifying oil and water in carbonate rocks. The method comprises the following steps of: acquiring a primary wave transmission signal of a seismic three-dimensional work area; carrying out pre-stack processing on the primary wave transmission signal; carrying out conventional seismic horizon calibration and explanation on seismic data obtained after carrying out pre-stack processing; carrying out inversion of a wave impedance on the seismic data obtained after carrying out pre-stack processing; according to the wave impedance and the AVO (Amplitude Versus Offset) effect of the seismic data, extracting a frequency corresponding to the seismic data; carrying out normalization processing on the seismic data corresponding to the frequency; and according to a result of the normalization processing, carrying out oil and water identification. Images can be simultaneously formed on a plane and a section; the method and the system are more convenient for the oil and water identification of a single well point and the statistic analysis of the geological rule on the plane; and the advantage of prediction before drilling of the method and the system is sufficiently played.

Description

technical field [0001] The present invention relates to the field of geophysical exploration, in particular to the field of oil and gas exploration and development, specifically a method and system for identifying oil and water in carbonate rocks. Background technique [0002] In recent years, carbonate rock has gradually become a very important new field of oil and gas exploration. Carbonate oil and gas fields in my country are usually deeply buried, and the formation of reservoirs is complex, mainly including syngenetic and penecontemporaneous karstification, epigenetic karstification and burial karstification. However, there are various types of reservoirs formed under different geological backgrounds and different genesis. Carbonate reservoirs usually have complex structures of pores, caves and fractures, with strong heterogeneity. It is not easy to accurately predict the type of carbonate reservoirs in exploration, but it is even more difficult to distinguish the compl...

AI Technical Summary

Problems solved by technology

But the traditional AVO analysis is only concerned with the elastic parameters on both sides of the medium interface

In addition, the traditional AVO technology is inconvenient in practical applications: It is not completely reliable to rely on naked eye observation to find amplitude enhancement or weakening phenomena on numerous 3D seismic sections, and it is easy to cause omission or repetition; it is not convenient to map on the plane Analyze the distribution law of geological phenomena on the plane

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