Shale Gas Potential in Bintuni Basin - New Insights to the Future Hydrocarbon Resources in Indonesia

Shales are fine-grained sedimentary rocks that can be rich sources of petroleum and natural gas. Shale gas refers to natural gas that is trapped within shale formations which are trapped in three ways: 1) adsorbed onto insoluble organic matter, 2) trapped in the pore spaces of the fine grained sediments interbedded with shale much like conventional reservoirs, and 3) confined in fractures within the shale itself. Generally, for shales to have produced gas they must fulfill five criteria: thermal maturity, vitrinite reflectance, reservoir thickness, total organic carbon content, and high brittleness index. This paper will explain about potential natural shale gas in Bintuni Basin. The basin is a Paleozoic basin located within the Bird's Neck Papua. The stratigraphy on Bintuni Basin composed by: Kemum Formation, Aifam Group (Aimau Formation, Aifat Formation, and Ainim Formation), Tipuma Formation, Kembelengan Group, Warapi Formation, Faumai Formation, Sago Formation, Kais Formation, Klasafet Formation, and Stenkool Formation. The Ainim Formation is comprised of predominantly organically rich succession, deposited in fluviatile to deltaic environment. This shale exhibits the criteria required for potential natural gas recovery: adequate total organic carbon (with range 8,7%-88%), thickness approximately 450 feet, and have stable clay minerals.