WELLBORE STABILITY ANALYSIS USING INTEGRATED GEOMECHANICAL NODELING IN FIELS, MUSI HIGH AREA, SOUTH SUMATRA BASIN

• Main Author: Suryadi, Heri
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/87084
• Institution: Institut Teknologi Bandung

Field S is located in the Musi High area, part of the South Sumatra Basin, and exhibits abnormal pressure conditions, specifically overpressure. This study analyzes data from 17 wells to address drilling problems related to wellbore stability, such as stuck pipes and lost circulation. The dataset includes well reports, wireline logs, rock mechanics data, and threedimensional seismik data, used to evaluate pore pressure, in situ stresses, rock mechanics parameters, and safe mud weight values, as well as to develop one-dimensional and three-dimensional geomechanical models. The results show that wellbore instability in the study area is primarily influenced by geological conditions, particularly the penetrated lithology and the drilling mud design. Clay lithology contributes to swelling issues that can cause wellbore collapse. Excessive mud weight relative to pore pressure can result in lost circulation and stuck pipes. Based on these findings, drilling design recommendations for new wells have been proposed, including casing design and recommended mud weights ranging from 1.03 to 1.41 SG.