ANALISIS STRUKTUR DAN REKONSTRUKSI PALINSPASTIK BLOK OGAN KOMERING BARAT, CEKUNGAN SUMATRA SELATAN

• Main Author: Ashari, Maulana
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/28798
• Institution: Institut Teknologi Bandung

South Sumatra Basin is a back-arc basin formed by the interaction between Indo- Australian plate and Eurasian plate. It is one of the largest sedimentary basins in Indonesia that has been proved as hydrocarbons bearing basin. The development of structural patterns, geological condition and evolution of the South Sumatra Basin shows more complexity than other basins in Sumatra. The purpose of this study are to determine condition of subsurface structures, development of structural patterns, tectonostratigraphy of study area, and history of the formation of basin through palinspastic reconstruction. The dataset used for this study includes two-dimensional and three-dimensional seismic cross sections, checkshot and eleven well logs. The methods used for this study are division of tectonostratigraphy unit, structural analysis on seismic cross section, subsurface structure map analysis, structural pattern analysis, palinspastic reconstruction and sedimentation analysis. The results of structural analysis and palinspastic reconstruction indicate that the study area is influenced by several deformation phases, namely the extensional phase (Eocene - Early Oligocene), stable tectonic phase (Early Oligocene – Late Miocene) and contractional phase (Late Miocene – Plio-Pleistocene). The extensional phase represented by northwest-southeast, north-south, and northeast-southwest listric normal faults that forms half-graben basin. A stable tectonic phase indicates a differential compaction event that is interpreted as a result of the height morphology of the basement and the difference nature of lithology. The contractional phase represented by northwest-southeast reverse fault and anticline, northeast-southwest strike slip faults with flower structure geometry. The strike slip faults formed an en-echelon pattern on the structure map.