A Quantitative Evaluation Method of 3D Fault Sealing Based on In-situ Stress Distribution

Abstract

The present invention relates to the field of petroleum exploration, in particular to a method for quantitatively evaluating fault three-dimensional sealability based on in-situ stress simulation, which comprises the following steps: step 1, testing rock strength mechanical parameters; step 2, testing the magnitude and direction of current in-situ stress; 3. Establish a mechanical model of the fault structure; Step 4, calculate the sealing evaluation parameters; Step 5, optimize the fault sealing index; Step 6, evaluate the three-dimensional sealing of the fault. The method of the present invention can effectively evaluate the three-dimensional sealability of faults from the perspective of in-situ stress, effectively select four quantitative evaluation indicators that play a decisive role in fault sealability, and provide a basis for the establishment of reservoir-forming geological models of fault-block reservoirs and the prediction of remaining oil distribution. A reliable basis is provided, and the risk and cost of exploration and development are reduced.

Description

technical field [0001] The invention relates to the field of petroleum exploration, in particular to a method for quantitatively evaluating the three-dimensional sealability of faults based on ground stress simulation. Background technique [0002] In the theoretical research and exploration practice of oil and gas accumulation, the study of fault sealing has always been a difficult problem for oil and gas geologists. As early as the 1960s, people began to try to evaluate the fault sealing. So far, a series of relatively mature fault sealing evaluation methods have been formed. Generally speaking, they can be summarized as qualitative and quantitative or semi-quantitative evaluation methods. Specifically, modern testing and mathematical analysis methods are mainly used to realize the transformation of single discipline and single method to multidisciplinary and multi-angle, and basically realize quantitative or semi-quantitative research. At present, there are mainly lithol...

AI Technical Summary

Problems solved by technology

First of all, the fault plane exists in a three-dimensional space, and many factors such as lithology distributed in this space are not static, and need to be evaluated at each spatial position, that is, in the process of fault sealing evaluation, it must be uncertain. In order to illustrate the credibility of the evaluation; secondly, the previous evaluation of in-situ stress and fault sealing was limited to the calculation of the normal stress of the section and the relationship between the displacement pressure of the two reservoirs, without considering the maximum principal stress , shear stress and fault sealing are closely related, thus restricting the reasonable characterization of the three-dimensional sealing of faults and affecting the accurate evaluation of oil and gas resources

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