Publications

Timor Island, which is located in eastern Indonesia has a complicated history in term of tectonic setting. Field observation in West Timor has yielded the footprint of collision between northern margin of Australian continent with Banda Arc subduction system which is represented by numerous exposures of different lithologies ranging from Permian to Quarternary. The key outcrops include the extensive mélange of Bobonaro Formation, deep water deposits of shale and siliceous limestone, mud volcanoes, and exposure of potential source rock in West Timor.The mélange deposit are consisted of various rocks trapped in a clay matrix which is interpreted as a shale diapir by looking at several indication such as the scaly shale, nature of blocks and its relationship to surrounding rocks. Fault analysis also confirmed several shear zones which are correlated with the occurrence of mud volcanoes. Several mud volcanoes show oily impression on the surface of the deposits. These fault-related shale diapirs show the existence of petroleum generation in West Timor.Furthermore, the collision process had exposed several lithologies which are interpreted as source rock for hydrocarbon manifestation in Timor. Several outcrop samples from different formation, such as Bisane, Aitutu, Wailuli, Nakfunu, Ofu, and Bobonaro Melange complex Formation were acquired from Soe and Kolbano Block. Fifteen samples were collected during the field work for geochemistry analysis which includes TOC, Rock-Eval pyrolysis, thermal alteration index and vitrinite reflectance. The result suggests that the Aitutu and Wailuli Formation are the best source rock candidates in West Timor with 0.75-1 % TOC and appear to be gas prone (Type III). Maturity is ranging from mature to overmature.