Calculation method of well controlled shale oil reserves based on Monte Carlo principle

This paper proposes an improved volume method based on Monte Carlo method to address the issue of low accuracy in calculating single well controlled reserves in shale oil horizontal wells. This method first divides the calculation area into units. Then, the probability distribution function of parameters within each unit is obtained through spatial interpolation method. Finally, the Monte Carlo method and volume method are used to calculate the reserve calculation results for each unit, and the well control reserves in the area are obtained by discretizing and accumulating the calculation results of all units. This paper proposes an interpolation method that integrates XGBoost and spatial semi-variogram to perform spatial interpolation on shale porosity in a certain area. Compare the accuracy of each interpolation method using evaluation indicators such as MAE, MSE, MAPE, etc. After comparison, the spatial XGBoost interpolation method integrating semi variogram has an accuracy improvement of over 15% compared to traditional methods, and an accuracy improvement of over 4% compared to the new machine learning spatial interpolation method. This proves that the method proposed in this paper can effectively improve interpolation accuracy.