Proceedings, Indonesian Petroleum Association
Thirty-Fourth Annual Convention & Exhibition, May 2010
Finding Remnants of the Tethys Oceans in Indonesia: Sutures of the Terranes Amalgamation and Petroleum Implications
Awang Harun Satyana*
Indonesia was built by a number of terranes rifting and drifting from Gondwana during Early Devonian to Paleogene. Separation of the terranes from Gondwana was accommodated by opening of a series of successively Tethyan oceans called the Paleo-Tethys, Meso-Tethys and Ceno-Tethys. The amalgamation of the terranes had closed these Tethys oceans to become sutures. Finding remnants of the Tethys oceans is therefore recognizing their sutures.
The study found five belts of sutures preserving the Paleo-Tethys, Meso-Tethys and Ceno-Tethys oceans in Indonesia. The sutures are made up of oceanic affinities. The Paleo-Tethys sutures are: (1) Karimun-Bangka suture in east offshore Sumatra marking the amalgamation between East Malaya and Sibumasu (Malacca part) terranes and (2) Natuna-Belitung suture marking the amalgamation between Southwest Borneo and East Malaya terranes. The Meso-Tethys sutures are: (1) Takengon-Bandarlampung suture in western Sumatra marking the amalgamation between Sibumasu (Mergui part) and Woyla terranes and (2) Meratus-Bawean suture marking the amalgamation between Southwest Borneo (Schwaner part) and Paternoster-Kangean terranes. The Ceno-Tethys suture is East Sulawesi Ophiolite Belt marking the suture of amalgamation between the Banggai microcontinent and western Sulawesi terrane.
Several sedimentary basins in Indonesia had developed in association with reactivation of these Tethys sutures. Ombilin pull-apart basin developed associated with reactivation of Meso-Tethys Takengon-Bandarlampung suture in West Sumatra area. Producing Barito and Banggai basins developed related to uplifts of the Meratus and East Sulawesi sutures, respectively. The suture has also been known affecting thermal history of sedimentary basins such as the Mutus Assemblage, a splay of Paleo-Tethys suture in CentralSumatraBasin. Recognizing sutures of Tethyan oceans in Indonesia is important for understandings of tectonic concept of ‘from Gondwana dispersion to Asia accretion and its associated sedimentary basin formation.