Neogene tectonics and orogenesis of Indonesia

Author : T.O. Simandjuntak
Publication : Bulletin of the Geological Society of Malaysia
Page : 43-64
Volume Number : 33

Bulletin of the Geological Society of Malaysia, Volume 33, Nov. 1993, pp. 43-64


Neogene tectonics and orogenesis of Indonesia


Geological Research and Development Center (GRDC), Jalan Diponegoro 57, Bandung, Indonesia


Abstract: The present tectonic configuration of the Indonesian archipelago is thought to have been developed during Neogene times, and shows a triple convergence, which is due essentially to interaction of three megaplates: the westward-moving Pacific Plate, the northward-moving Indo-Australian Plate and the south-southeastward-moving Eurasian Plate.

The archipelago is built up of at least 5 distinctive crustal elements including 1) Sunda Shield (SE Eurasian Plate) 2) Indian (Oceanic) Plate, 3) Australian Craton 4) Pacific Plate and 5) Transitional Complex. Each unit consists of several distinctive tectonic units.

This tectonic convergence was subsequently followed by the development of orogenic belts in most parts of the region, which kinematically can be recognized and divided into 4 types:

1. Sunda Orogeny in western Indonesia due essentially to a back-arc thrusting in Jawa and Nusatenggara, and transpressional movement of the Barisan Fault System in Sumatera. The orogeny gave rise the development of the Southern Mountain Ranges in Jawa and the Barisan Mountain Ranges in Sumatera, which are coincident with the fold and fault belt. In Sumatera the belt shows a typical flower structural setting.

2. Banda Orogeny in Sulawesi and its surroundings due essentially to the development of a Tethyan type convergence together with the transcurrent movement of the Palu-Koro Fault System, which give rise the development of mountain ranges in Sulawesi.

3. Melanesian Orogeny in Irian Jaya and Papua New Guinea and Sahul Platform due to the development of thin-skinned tectonics, causing the development of the Central Irian Jaya Fold and Thrust Belt coincident with the Central Irian Jaya Mountain Ranges.

4. Talaud Orogeny in the northern Maluku region due to the development of double arc collision coupled with the transpressional movement of southern extension of the Philippine Fault System giving rise the development of the imbricated Talaud-Tifore ridge in the form of flower structure, which is partly emerged above sea level.