Engineering Geology

Engineering Geology

3D modeling to determine the geomechanical parameters of the Asmari reservoir and the principal stresses in one of the fields in southwestern Iran

Authors
Mohammad Reza Haddad Tehrani 1
Mehdi Talkhablou 1
Mohammad Reza Asef 1
Mehdi Ostad Hasan 2
1 kharazmi uni.
2 Daqing University, China
10.22034/JEG.2025.19.2.1014282
Abstract
Complex carbonate reservoirs, such as the Asmari Formation, present challenges to the accurate determination of geomechanical parameters and effective stresses due to high lithological and structural heterogeneity. The objective of this study is to develop a comprehensive three-dimensional model of geomechanical parameters and effective stresses in the Kupal oil field. Well log, core, and seismic data were used, and three-dimensional modeling was performed using the Sequential Gaussian Simulation (SGS) method based on variogram analysis. The prevailing stress regime was validated using FMI logs and wellbore breakout analysis. Additionally, a one-at-a-time sensitivity analysis was conducted on key parameters, including static Young’s modulus, Poisson’s ratio, cohesion, internal friction angle, and pore pressure. Results indicate that the maximum vertical effective stress (σv) is 87 MPa and the maximum horizontal effective stress (σHmax) is 127 MPa. Analysis of wellbore imaging data confirms a normal faulting stress regime (σv>σHmax>σhmin) in the field. Stress concentration around minor faults was also identified. The model was validated against one-dimensional models achieving 88% agreement. The findings of this study can be applied to well design, gas injection, and reservoir stability assessment in the Kupal field.
Keywords
Asmari reservoir
3D geomechanical modeling
Sequential Gaussian Simulation
effective principal stress
Sensitivity Analysis
normal faulting regime
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