INTEGRATED STUDY OF REGIONAL TECTONICS, GEOLOGIC STRUCTURES, AND PALEOGEOGRAPHY RECONSTRUCTION TO DEVELOP CBM CLEAT MODEL IN TANJUNG II BLOCK, SOUTH BORNEO

摘要

Cleats have become an important consideration for successful exploration operations in Coal Bed Methane (CBM) exploitation. Understanding orientation and distribution of cleats is critical to drilling recommendations for exploration and exploitation to achieve maximum CBM production. In this study, cleat and permeability analyses are accomplished by creating a conceptual model based on integration of regional tectonics, geological structures, and paleogeography reconstruction. This comprehensive study was done in the Tanjung II Block, South Borneo, as one of the CBM Blocks in Indonesia owned by Pertamina. In this study, we constructed geological maps and cleat measurements in coal outcrops, including the coal sampling from the Warukin and Tanjung Formations. Regional structure maps of the study area were combined with the cleat line map that was obtained from the fieldwork. The dominant structural lineament in the Study Area is NE-SW, while the cleat line has E-W direction. It confirms that structural lineament and cleat fractures are perpendicular. The structural and stratigraphic correlation that depicts the distribution of coal zone A, B, C, and D were done from well data and seismic interpretation. The paleogeography maps of each coal zone were reconstructed by using these interpretations.