Estimating the shear sonic log using machine learning methods, and comparing it with the obtained data from the core
Subject Areas :
Houshang Mehrabi
1
,
Ebrahim Sfidari
2
,
Seyedeh Sepideh Mirrabie
3
,
Sadegh Barati Boldaji
4
,
Seyed Mohammad Zamanzadeh
5
1 -
2 - 2. Assistant Professor, Petroleum Geology Group, Research Institute of Applied Science, Academic Center for Education, Culture and Research, Tehran, Iran
3 - 3. Graduated Master of Science, School of Geology, College of Science, University of Tehran, Tehran, Iran
4 - 1. Master of Science, Petroleum Geology Group, Research Institute of Applied Science, Academic Center for Education, Culture and Research, Tehran, Iran
5 - University of Tehran
Keywords: Python, Estimation, Shear Sonic Log, Machine Learning,
Abstract :
Machine learning methods are widely used today to estimate petrophysical data. In this study, an attempt has been made to calculate shear sonic log (DTS) from other petrophysical data using machine learning methods and compare it with the sonic data obtained from the core. For this purpose, computational methods such as Standard Deviation, Isolation Forest, Min. Covariance, and Outlier Factors were used to normalize the data and were compared. Given the amount of missing data and box plots, the Standard Deviation method was selected for normalization. The machine learning methods used include Random Forest, Multiple Regression, Boosted Regression, Support Vector Regression, K-Nearest Neighbor, and MLP Regressor. Multiple regression had the lowest evaluation index (R2=0.94), while Random Forest regression had the highest correlation between the estimated shear sonic log and the original shear sonic log with an evaluation index of 0.98. Therefore, Random Forest regression was used for the final estimation, and to prevent data generalization or overfitting, the GridSearchCV function was used to calculate optimal hyperparameters and final estimation. The estimated sonic log showed a very high similarity with the core data.