ANALISIS POLA PENGENDAPAN FORMASI

• Main Author: Pratama Putra, Rifky
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/77306
• Institution: Institut Teknologi Bandung

Bentu area is located in Central Sumatera Basin. Most of the wells in this area produce and explore shallow biogenic gas delivered from “B” Fm. The purpose of this study are to identified geometry and determine sedimentation pattern of “B” Fm. and then correlating it with tectonic development model in Central Sumatera Basin. Study of geometry is based on sequence stratigraphic on well log data, conventional core and 2D seismic data. While the analysis of sedimentation pattern based on well data and seismic attribute instantaneous frequency. “B” Fm. has a complete system tract and divided into three interval that are; SB0-TS interval namely Lowstand System Tract (LST), TS-MFS interval namely Transgressive System Tract (TST) and MFS-SB1 interval namely Highstand System Tract (HST). Conventional core analysis indicates that facies in the transgressive system tract (TST) interval is tidal channel, tidal bar and tidal flat that are develop in tidal estuarine environment. Tectonic developments in the study area is refers to the tectonic development of Central Sumatera Basin made by Heidrick and Aulia (1993). F3 phase related to NE-SW compression which cause the uplifting of NW-SE old structure and result thrust faults (inversion). This last deformation related to regional deformation such as the activity of Semangko Fault, volcanism and the major uplifting of Barisan Mountains that affect the deposition patterns of “B” Fm. from northeast and southwest direction. Three main trap are identified in study area; bounded anticline fault closure, four-way dip closure and stratigraphic trap.