Publications

Taliabu Island is located in the Province of North Maluku, Eastern Indonesia. Some sandstone samples from Bobong Formation were taken from the island for analysis of geometry, sedimentary texture, transport mechanism, depositional environment and diagenetic processes to understand their reservoir qualities. Eight samples from eight outcrops were analyzed it was observed that the grain size distribution is from cobble (64 mm/-6 phi) to fine sand (0.125 mm/3.0 phi), poorly sorted - medium sorted, hard - very hard, angular – sub angular. The quartz and feldspar grains are dominant component minerals and sedimentary texture, sedimentary structure and granulometry analysis show that the depositional environment of this sandstone is terrestrial – shallow marine (alluvial fan, fluvial, beach). Sandstone types of the Bobong Formation indicated by petrography analysis are Quartz Arenite and Feldsphatic Arenite and their tectonic provenance were from continental block (Banggai granite and low grade methamorphic rock), precisely, the craton interior and basement uplift deposited during early Jurassic – middle Jurassic period. Effective porosity ranges from 8.8 % to 19 % whith classification poor – good reservoirs. Sandstones deposited in terrestrial environment have better reservoir quality than beach deposit environment. Compaction was very intense in beach environment, closing porosity with poor reservoir as a result. * University of Padjadjaran ** Niko Resources, Ltd Keywords: Jurassic Sandstone, Bobong Formation, Eastern Indonesia.