Challenge for Mesozoic Hydrocarbon Exploration in the Eastern Indonesia
Abdullah Sodik, M. G. Rukmiati, and Nelson Sitompul
The eastern part of Indonesia covers approximately 3 million square kilometers, 35 percent being landmass and 65 percent covered by ocean. Only three of 38 sedimentary basins are producing hydrocarbon (Salawati, Bintuni, and Seram Basins). Oil and gas have discovered in the Lariang, Bone, Timor, Banggai, Sula and Biak Basins, however the discoveries have not developed yet. Hydrocarbon systems in Northern Australia and Papua New Guinea give the major contributions to the geological idea of Pre-Tertiary section in the less explored area in the Eastern Indonesia.
The Triassic-Middle Jurassic marine carbonaceous shale sequences are the main hydrocarbon source rock in the Irian Jaya and surrounding area (Buton, Bula and Seram basins). The main Mesozoic reservoir are the Kembelangan Formation in the Bintuni Basin of Irian Jaya and Bobong Formation in the North Sula Region.
Exploration play types in the Eastern Indonesia can be divided into five types: (1) Peri Cratonic, (2) Marginal Rift Graben, (3) Thrust Fold Belt Island Arc, (4) Early Collision, and (5) Microcontinental Block-Advanced Collision.
Recent discoveries through Mesozoic section in Eastern Indonesia are: Roabiba-1 (1990) in Bintuni Basin-Irian Jaya (Kambelangan Formation); Loku- 1 (1990) in North Sula region (Pre-Tertiary sediments); Oseil-1 (1993/94) in Bula-Seram Basin (Jurassic Manusela Formation); Elang-1 (1994); Kakaktua-1 (1994) and Laminaria-1 in North Bonaparte Basin (Upper Jurassic Sands).
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California