Geochronology and Metamorphic Rocks Evolution of Rumbia Mountains, Southeast Arm of Sulawesi, Indonesia

The Rumbia Mountains, which in this study named Rumbia schist Complex is an east-west oriented, composed by a high-pressure/low-temperature, and a medium-pressure/low-temperature metamorphic rocks. Identified as glaucophane schist, chlorite schist, and mica schist. The radiometric age dating results using 40Ar/39Ar method giving the age spectrum between 26.4 ± 0.23Ma to 7±0.6 Ma. While the Bantimala Melange Complex, South Sulawesi from white mica on glaucophane schist giving ages 114 Ma and 110 Ma. This is very defferent with previous researchers hypothesized. Some authors argue, that Rumbia schist Complex and Mendoke Mountains in the Southern part of Southeast Sulawesi is the same path with Pompangeo schist Complex in Central Sulawesi, and the accretion zone of Bantimala Melange Complex in South Sulawesi. The Pompangeo schist Complex using the K-Ar method, obtained ages among 114±3.0 Ma to 108±2.5 Ma, and the Bantimala Melange Complex of Glaucophane Schist be obtained a range ages between 132±7 Ma to 115±6 Ma, and from white mica minerals in eclogite obtained age 137±3 Ma