Methods for reservoir avo analysis under sedimentary facies control

Abstract

The invention proposes a method for performing a reservoir AVO analysis under sedimentary facies control. The method comprises: on the basis of logging data and seismic attribute data, sedimentary facies units are divided; according to a drilling well core and a slice identification result, differences of main mineral components of reservoirs of all sedimentary facies units are obtained by combining an analysis result of a process of sedimentation; qualitative differences of rock physical properties of reservoirs of all sedimentary facies units are obtained; on the basis of the differences of the physical properties of the rocks of reservoirs in different sedimentary facies units, reservoir AVO feature differences in different sedimentary facies units are obtained, and the differences of the AVO features are verified by carrying out AVO direct deduction of the on-ground reservoir and borehole-side practical seismic trace gather AVO analysis; and according to the verified differences of the reservoir AVO features in different sedimentary facies units, reservoir AVO analyses are carried out in all sedimentary facies ranges to obtain longitudinal and horizontal distribution of reservoirs in all sedimentary facies units. According to the invention, distribution boundaries of AVO features are divided and reservoir prediction is carried out within all boundary lines, so that prediction multiplicity is reduced and the exploration success rate is improved.

Description

technical field [0001] The invention relates to the technical field of petroleum exploration, in particular to a method for analyzing reservoir AVO under the control of sedimentary facies. Background technique [0002] With the increasing demand for oil and gas resources in modern society, the degree of oil and gas exploration and development continues to deepen. complex, gradually turning to lithologic traps, composite traps, and non-"bright spot" oil and gas reservoirs, etc., which makes it difficult for conventional exploration techniques to identify oil and gas distribution. For example, AVO analysis techniques often fail to It has multiple solutions, therefore, certain methods are needed to improve the accuracy of AVO analysis technology prediction, which plays an important role in reducing exploration risks and improving the success rate of exploration. [0003] AVO, that is, the amplitude varies with the offset. The offset refers to the distance between the seismic w...

AI Technical Summary

Problems solved by technology

However, in complex geological environments, the AVO characteristics of reservoirs are often not fixed, and may appear as two or more types. In this case, the usual practice is to subjectively divide each AVO type according to the distribution of different types of wells The disadvantage of this approach is that it does not analyze the root cause of the different AVO types, and only summarizes the rules based on the distribution of a small number of sample points, which has poor reliability, especially when the exploration area is large but only a small number of wells are drilled.

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