GEOLOGY AND KINEMATIC ANALYSIS OF BALANTAK FAULT, BALANTAK AREA, BANGGAI REGENCY, CENTRAL SULAWESI

• Main Author: Endinanda, Ferdi
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/42096
• Institution: Institut Teknologi Bandung

Indonesia needs new ventures to fullfill its energy demand for a sustainable country. East Indonesia has potential with its abundant hydrocarbon reserve which one of the producing site is Senoro Gas Field at East Sulawesi. Sulawesi is known to its convergence tectonic complexity of the triple junction that forms the island. Balantak is one of the sub-districts in Banggai Regency, Central Sulawesi Province. The research area is 100 km2 located at the coordinates of UTM 527000 - 537000 m T and 9900000 - 9910000 m U in zone 51S with WGS84 datum. Structures that has been developed in the area is the features of geological processes since Late Cenozoikum on Tertiary basins in the area. This study presents geological mapping and deformation style that occurred within the area of study on providing new information with 3D geology model structural trap types in supporting the development of oil and gas fields. This research method was conducted using field observation, petrographic analysis, biostratigraphic analysis, and kinematic analysis of fault-slip data. The landscape of the research area is in the form of hills and valleys which are generally affected by the lithology of the rocks and the geological structures formed. This can be seen from the topography, rectangular and trellis river patterns found in the study area. There are two geomorphological units in the study area, namely the Boloak Karst Hills Unit, and the Balantak Fault Zone Ridge Unit. Lithology scattered in the study area has the characteristics of sedimentary rocks that is Grainstone intercalating Calcareous Sandstone and Rudstone consist of limestone fragments. The study area also has crystalline rocks in the form of ultramafic rocks such as Peridotite, Serpentinit, Gabbro and Basalt. Rock units in the study area have a Middle Cretaceous age to Late Miocene. Structural analysis indicates that the generation of thrust fold belt and tearing faults along the study area occured because the collision of Banggai-Sula with Sulawesi East Arm. The orientation and shape of strain ellipsoid is a pure shear transpression which is the Balantak Fault as its plane of movement. Similiarities of the structure pattern with the model shows that the type of traps are en echelon thrust and fold while the tearing faults are riedel synthetic to the Balantak dextral strike-slip movement that developed offset on the folds.