Core pore structure change detection and analysis method

Abstract

The invention provides a core pore structure change detection and analysis method which comprises the following steps: carrying out CT scanning on a core sample (without pore structure change) so as to obtain related CT values of a dry core sample and a complete saturation type initial fluid core sample; adjusting a foreign fluid CT value and an initial sample fluid CT value to be consistent by analyzing a core sample CT scanning principle, so that in a flowing test process, the CT value of the core sample changes only related with the change of a pore structure; carrying out a core fluid flowing test on the core sample, and simultaneously carrying out the CT scanning so as to obtain related test data, such as the CT values, when a foreign fluid and an initial sample fluid simultaneously exist (at the moment the core sample has the possibility to be subjected to the pore structure change) in the test; calculating so as to obtain core pore structure change parameters according to the test data; and obtaining a core analysis curve and a CT scanning image according to the core pore structure change parameters, so that specific locations and areas on which the pore structures change in a core can be accurately detected, and simultaneously the corresponding quantitative analysis can be carried out on the locations and areas on which the pore structures change.

Description

technical field [0001] The invention relates to a method for detecting and analyzing changes in the pore structure of a rock core, which is particularly applicable to the change of the pore structure caused by various potential reservoir damages in the flow test of the rock core. Background technique [0002] In the process of oil field development, the formation energy is usually supplemented by injecting various fluid media, such as water injection and CO injection. 2 And so on, so as to achieve the goal of maintaining stable oil field production and finally obtaining an ideal recovery rate. However, when the foreign fluid does not match the reservoir, the clay minerals in the reservoir are likely to hydrate, swell, disperse, and migrate, resulting in a decrease in the seepage capacity of the reservoir, which in turn causes reservoir damage to varying degrees. . Reservoir sensitivity refers to the sensitivity of a certain damage in the reservoir to external induced condi...

AI Technical Summary

Problems solved by technology

However, this method has the following two shortcomings, that is, it cannot accurately describe the specific area where the pore structure changes in the core, and it also lacks quantitative analysis of such pore structure changes

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