SANGKULIRANG REGIONAL STRIKE SLIP FAULT ANALYSIS, FOR STRUCTURAL EVOLUTION IN WEST SANGATTA AREA, NORTHERN KUTAI BASIN

• Main Author: Sondang Martinauly, Bertha
• Format: Theses
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/74385
• Institution: Institut Teknologi Bandung

The main objective of this research is to have better understanding in structural evolution in Kalimantan Kutai Energi working area, West Sangatta PSC as a part of Kutai Basin regional tectonism, in this case Sangkulirang fault. Sangkulirang fault is a sinistral regional strike slip fault that lies in the northern part of the study area, this fault extended in the northern margin of Kutai Basin with NW-SE trending and then become a part of Palu Koro fault system in Sulawesi. Palinspatic reconstruction has enabled to recognize the structural evolution in the study area. More than 65 seismic lines and 5 exploration wells, have been interpreted to have better understanding in structure and sedimentation. Interpretation and the result of palinspatic reconstruction breaks the study area into 3 discrete phases 1) Eocene syn rift phase 2) Early Oligocene post rift 3) Late Oligocene syn inversion. The structural pattern in the study area were interpreted as the inversion fault, these fault have rejuvenated the Eocene tensional fault. In Miocene time, the regional strike slip fault is believed to rotate the northern part of the study area. This movement separates the structural trend in the study area NNE – SSW in the southern area become NE-SW in the northern part. As a result of the tectonic event that occurred in the study area, this area is believed to have potential hydrocarbon reserves. As in syn rift phase, the rifting initiation have a good potential in the source rock and reservoir deposition. Post rift phase, where the tectonic is not as active as syn rift phase and also transgression, shale is being deposited and act as the seal for the underlying reservoir. The syn inversion phase creating trap for hydrocarbon accumulation.