The purpose of this study is to evaluate and classify the uncertainties arising from performing and analyzing test injections before fracturing. Pre-fracture test injection analysis is performed widely, but usually the values obtained are taken into account without reference to uncertainties. Existing hydraulic fracturing techniques identify multiple sources of uncertainty, and no evaluation and classification system has previously been proposed to determine the accuracy of the resulting data. Uncertainties of interpretation can be evaluated by the engineer performing the analysis, but such evaluation is subjective and difficult to measure. In the course of this study, a statistical analysis was performed to numerically estimate the level of uncertainty in the analysis. The proposed solution includes an assessment of the degree of reliability of the data obtained from the analysis, which allows for the introduction of refined adjustments to the parameters of the main stage of hydraulic fracturing.
The scientific novelty of the work lies in the evaluation and classification of uncertainties affecting the results of the analysis of test injections before hydraulic fracturing. For the first time, the classification is proposed and statistical analysis is applied, aimed directly at assessing the degree of reliability of test injection data, as well as proposed metrics that characterize the reliability and uncertainty of the analysis data. As a result, the proposed approach makes it possible to supplement the numerical values of the parameters obtained in the analysis with an assessment of their reliability, including those based on statistical data.
fracturing, test injection, Minifrac, Minifrac, Datafrac, sandstone fracturing, fracturing conditions evaluation, fracturing quality control, Minifrac accuracy metrics, Minifrac validity, Minifrac information reduction factors, fracturing risk assessment, fracture parameter forecast, correlation analysis
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