STRUCTURAL STYLE ANALYSIS AND ITS RELATIONSHIP WITH HIDROCARBON DISTRIBUTION AT MUTARA FIELD BLOK SANGA-SANGA, EAST KALIMANTAN

• Main Author: NUGRAHA, TEGUH
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/74447
• Institution: Institut Teknologi Bandung

Mutiara field is located at the most southern of Sanga-Sanga Blok where is administratively included into province of East Kalimantan. The field is about 60 km away from provincial capital, Samarinda, towards to southwest. The field extended 230 km2 bounded by Pamaguan Field to the north, Samboja Field to the south, offshore line to the east and Mutiara thrust fault to the west. It is part of Production Sharing Contract (PSC) area of Vico Indonesia. Reservoir is filled by hydrocarbon randomly either vertical or lateral in this field. Data wells that were drilled along the axis of anticline state that only 20% reservoir filled by hydrocarbon with varied hydrocarbon-water contact. That data demonstrate that there are certain mechanisms that control the distribution of hydrocarbon. Faulting indicated as the main controller in the distribution of hydrocarbon. 3D seismic data and seismic attribute semblance has been interpreted and analyzed to map fault that developed in this area. There are 3 fault orientations that developed in this area which is Northeast-Southwest trending thrust fault, East-West trending normal fault and Northwest-Southeast trending strike slip fault. Statistical calculations indicated that the strike slip faults oriented northwest - southeast, affecting distribution of hydrocarbons in E interval. By plotting the percentage of the reservoir that contains hydrocarbon with the distance to the fault is obtained that for a sandstone reservoir in E level has good relationship. While for the deeper interval there are not relationships. These faults act as hydrocarbon migration pathways at further stages which affect only a shallow interval Statistical data also showed that the deeper reservoir intervals have bigger percentage of hydrocarbon-filled reservoir. This showed that in this field vertical migration more dominant than lateral because the source rock is at a deeper level so that the closer the reservoir to the source rock has bigger chances to be filled by hydrocarbons. Hydrocarbons migrated vertically through the fault plane.