SEQUENCE STRATIGRAPHY OF EAST AIR KOMERING, SOUTH PALEMBANG SUB-BASIN

• Main Author: NURHASANUDIN RACHMANTO, MASRURI
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/16393
• Institution: Institut Teknologi Bandung

The purpose of this study is to establish the sequence stratigraphy of Early to Middle Miocene sediments of Talang Akar Formation, Baturaja Formation, Gumai Formation, Air Benakat Formation, and Muara Enim Formation in East Air Komering area, South Sumatra. Method used in this study is stratigraphic facies analysis utilizing GR and SP wireline log data from three wells, which are AR-1, CM-1, and JG-1. The study area resided at the southern edge of South Palembang Sub-basin, South Sumatra Basin. Currently, South Sumatera Basin is one of the Tertiary back-arc basins, which spread across the southern part of Sumatra land bearing north west – south east. Sequence stratigraphy analysis divides the Early to Middle Miocene sediments in the study area into nine sequence stratigraphy units bounded by nine sequence boundaries. Those nine units area, respectively from older to younger, are Sequence Unit 9, Sequence Unit 8, Sequence Unit 7, Sequence Unit 6, Sequence Unit 5, Sequence Unit 4, Sequence Unit 3, Sequence Unit 2, and Sequence Unit 1. Sequence Unit 9 deposited in inner neritic environment. Sequence Unit 8 deposited in shallow marine environment. Sequence Unit 7 deposited in shallow marine to swamp. Sequence Unit 6, 5, 4, and 3 deposited in inner to outer neritic. Sequence Unit 2 and 1 deposited in swampy to tidal mud flat. In general, the Early to Middle Miocene sediments were deposited in relatively shallow marine environment. There is tendency of shallow up and deepening upward from middle neritic to transitional (tidal) environment. The study area has undergone repeated changes of environment, which are insignificant. During Early Miocene to Middle Miocene, the study area was still in range of tidal to outer neritic environment.