General geology and petrography of metamorphic rock in Desa Anabanua, Barru Sub-Distric, Barru Regency, South Sulawesi, Indonesia

Geological mapping of 25km2 with the scale of 1:25000 were conducted in the Desa Anabanua, Barru Sub-District, Barru Regency, South Sulawesi, Indonesia. Geographically, this area located at between 4o 27’0” – 4o 29’30” South latitude and 119o41’0” – 119o 43’ 0” East longitude. The aim of the study is to produced updated map with better understand the geology of the study area and more specifically the petrography of the metamorphic rock in Desa Anabanua area. Unit lithology in the research area can be divided into three main unit. Description sequentially from the oldest to the youngest lithology unit are as follows Schist Unit, Ultramafic Unit and Limestone Unit. Both schist and ultramafic unit known as basement complex and the age is Triassic to Lower Creataceous while limestone unit is a part of Tonasa Formation with age is Eocene to Middle Miocene. Some part of this these rocks are chaotically mixed of igneous (peridotite, basalt and dacite), metamorphic (schist, garnet mica schist, blueschist, greenschist, phyllite, serpentinite and quartzite) and sedimentary rocks (limestone, claystone, chert and sandstone). These rocks are tectonically mixed as a result of subduction between the continental plates and oceanic plates. The geomorphology of the study area, Desa Anabanua can be divided into 2 units of morphology which is medium relief morphology unit and low relief morphology unit. In the research area, the main geological structures that occurred in the area such as folding and faulting. For petrography metamorphic rock, these rocks was determined based on texture, structure and composition of the minerals content. Based on these indication, it can be interpreted the type of the depositional environment of this unit and metamorphic grade.