3D-geological modelling using probabilistic approach to involve unaccounted reserves

Prospecting and exploration of uncounted resources is one of the key challenge for the oil and gas industry, requiring optimal allocation of budgetary funds. This article aims to enhance the reliability of reserve estimates while reducing investment compared with traditional exploratory drilling methods, by using a probabilistic model in constructing three-dimensional geological models. The authors developed probabilistic models for the studied fields using porosity and permeability data obtained from core samples. The methodology includes an original approximation techniques and interpolation of data based on stochastic distributions to update well-log curves and estimate reservoir properties under probabilistic conditions. The researchers calculated hydrocarbon reserves for both the original and the probabilistic geological models using the volumetric method. Next, they compared the total oil reserves obtained from the probabilistic models with those calculated from the original models. To evaluate the spatial distribution of the differences, authors compared linear reserve map generated by the probabilistic and conventional approaches. The proposed methodology enhances the accuracy of estimating uncounted geological reserves, reduces the need for additional exploration drilling, and supports more efficient field development planning, particularly under budgetary constraints.

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