TY - JOUR ID - 1668 TI - Wellbore Trajectory Optimization of an Iranian Oilfield Based on Mud Pressure and Failure Zone JO - Journal of Mining and Environment JA - JME LA - en SN - 2251-8592 AU - Yousefian, H. AU - Fatehi Marji, M. AU - Soltanian, H. AU - Abdollahipour, A. AU - Pourmazaheri, Y. AD - Drilling & Well Completion Technologies & Research Group, Research Institution of Petroleum Industry (RIPI), Tehran, Iran AD - Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran AD - School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran Y1 - 2020 PY - 2020 VL - 11 IS - 1 SP - 193 EP - 220 KW - borehole breakout KW - well trajectory KW - failure zone KW - critical pressure KW - Induced stress DO - 10.22044/jme.2020.8779.1768 N2 - Determination of the borehole and fracture initiation positions is the main aim of a borehole stability analysis. A wellbore trajectory optimization with the help of the mud pressure may be unreasonable since the mud pressure can only reflect the degree of difficulty for the initial damage to occur at the wellbore rather than the extent of the wellbore damage. In this work, we investigate the failure extension in different arbitrary inclination boreholes under different in-situ stress regimes. Assuming the plane strain condition, the Mohr-Coulomb, Mogi-Coulomb, and Modified Lade rock failure criteria are utilized. We present an analytical equation to determine the optimum drilling trajectory of an Iranian oilfield. In order to predict the degree of wellbore damage, the initial shear failure location, failure width, and failure depth of arbitrary wellbores are determined. Then a new model is derived to calculate the initial failure area of a directional wellbore because it is more efficient in a wellbore stability analysis. The results obtained show that in the target oilfield, the vertical and low-deviated direction is the optimum drilling path. According to the results of this work, optimization of the wellbore trajectory based on the estimated failure zone is a reasonable method if a considerable failure zone takes place around the borehole wall. UR - https://jme.shahroodut.ac.ir/article_1668.html L1 - https://jme.shahroodut.ac.ir/article_1668_041de262bdb7728886d347a154ef5af8.pdf ER -