Provenance Determination Of Sandstone Based On Petrographic Analysis In Bambaira And Ako Areas, Pasangkayu District, West Sulawesi Province

Abstract

West Sulawesi has a very connections with the tectonic process of the Makassar Strait, where the Makassar Strait is influenced by the process of plate expansion, as a result of the process formed a sedimentary basin composed of sedimentary rocks with rocks of diverse origin, the determination of rock origin (provenance) can help to reveal the tectonic setting and rock origin in the, to see the mineral content of existing sandstone constituents in the research area microscopically, the parameters used in determining the origin of rocks are quartz, feldspar and lithic fragments, the calculation of rock constituent minerals using the point counting method and then normalized for plotting on the provenance diagram and tectonic setting. The results of petrographic analysis on sandstone obtained the name of the Rock is lithic graywacke and quartz wacke. Rocks of origin in the research area are from Plutonic igneous rocks, volcanic igneous rocks, metamorphic rocks and sedimentary rocks, which are known based on the presence of monocrystalline quartz and polycstaline Quartz minerals, orthoclase minerals, sanidine minerals, volcanic lithic and sedimentary lithic,while the tectonic setting in the research area is magmatic arc and recycle orogen.