MULTIPLE REGRESSION METHOD IN DETAIL DERIVATION OF POROSITY AND PERMEABILITY FOR TELISA FORMATION EVALUATION IN KOTABATAK FIELD, CENTRAL SUMATRA BASIN

• Main Author: Mastoadji, Erry
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/70706
• Institution: Institut Teknologi Bandung

The study is located in Kotabatak field, Central Sumatra Basin which is structurally as a northwest – southeast trending asymmetrical anticline. The Kotabatak field is bounded in northeast side by trust fault which has same trending with anticline. The study is in Telisa Formation which is occupied 15% of total Kotabatak’s Original Oil In Place (OOIP). The Telisa Formation is a nearshore shallow marine clastic deposit, composed mainly of quartz, foraminiferal shells, glauconite, and siderite. Due to the hollow foram shells, the Telisa Formation is generally high porosity but low permeability. This because of the pore system in Telisa Formation has low connectivity. The challenge for petrophysicist in the study of Telisa Formation is determining accurate porosity and permeability in order to predict production performance, which can be used as a guide for further Kotabatak field development. A variety of techniques were used to address these uncommon problems, but the result still cannot close to the actual data. With this study the more accurate result is expected can be determine. The technique that used in this study is multiple regression method to derived porosity and permeability from core data and their correlation with more than one log data. More detail zonation such as facies and shale volume bin are also carried out to get more accurate result. 26 multiple regression equations have been succesfully obtained to derived porosity; while to derived permeability have been obtained 32 equations. The result of this study show the improvement of the accuracy on the porosity and permeability prediction.