Department of Petroleum and Energy Studies, School of Engineering and Technology, DIT University, Dehradun, India.
Data Science Research Group, School of Computing, DIT University, Dehradun, India.
Sci Rep. 2022 Oct 3;12(1):16551. doi: 10.1038/s41598-022-21075-w.
In recent years, well-test research has witnessed several works to automate reservoir model identification and characterization using computer-assisted models. Since the reservoir model identification is a classification problem, while its characterization is a regression-based task, their simultaneous accomplishment is always challenging. This work combines genetic algorithm optimization and artificial neural networks to identify and characterize homogeneous reservoir systems from well-testing data automatically. A total of eight prediction models, including two classifiers and six regressors, have been trained. The simulated well-test pressure derivatives with varying noise percentages comprise the training samples. The feature selection and hyperparameter tuning have been performed carefully using the genetic algorithm to enhance the prediction accuracy. The models were validated using nine simulated and one real-field test case. The optimized classifier identifies all the reservoir models with a classification accuracy higher than 79%. In addition, the statistical analysis approves that the optimized regressors accurately perform the reservoir characterization with mean relative errors of lower than 4.5%. The minimized manual interference reduces human bias, and the models have significant noise tolerance for practical applications.
近年来,试井研究见证了多项使用计算机辅助模型自动进行储层模型识别和特征描述的工作。由于储层模型识别是一个分类问题,而其特征描述是一个基于回归的任务,因此同时完成这两个任务总是具有挑战性。本工作结合遗传算法优化和人工神经网络,自动从试井数据中识别和描述均质储层系统。总共训练了 8 个预测模型,包括 2 个分类器和 6 个回归器。具有不同噪声百分比的模拟试井压力导数构成了训练样本。使用遗传算法仔细进行特征选择和超参数调整,以提高预测精度。使用 9 个模拟和 1 个实际测试案例对模型进行了验证。优化的分类器以高于 79%的分类准确率识别所有储层模型。此外,统计分析表明,优化的回归器可以准确地进行储层特征描述,平均相对误差低于 4.5%。最小化的人工干预减少了人为偏见,并且模型对实际应用具有显著的噪声容忍度。