ABSTRACT: Neogene tectonics of Indonesia

Simandjuntak, T. O. , Geological Research and Development Center, Bandung, Indonesia

Indonesia is one of the most active margins around the globe. The present tectonic configuration of Indonesia may represent a typical triple junction plate convergence, developed since Neogene times.

The Neogene tectonic evolution of Indonesia is marked by the development of distinctive styles of orogenic belts in different parts of the region. These orogenic styles provide a range of structural models illustrating the complexity and diversity of tectonic processes which may provide the key to the interpretation of other orogenic belts elsewhere in the world. Seven distinctive types of orogenies have been recognized within Indonesia: 1) the Sunda Orogeny in Jawa and Nusatenggara involves normal convergence producing an Andean type orogenic belt, 2) the Barisan Orogeny is associated with oblique convergence and major dextral transpressional wrenching in Sumatra, 3) the Talaud Orogeny in the northern Maluku Sea typifies a double-arc collision coupled with sinistral transpressional wrenching, 4) the Sulawesi Orogeny marks the collision of microcontinents with a subduction system and sinistral transpressional wrenching, 5) the Banda Orogeny involves an arc-continent collision between Australia and the subduction system in the southern Banda Arc, 6) the Melanesian Orogeny in Irian Jaya and Papua New Guinea is characterised by oblique convergence coupled with thin-skinned tectonic movements, and 7) the Dayak Orogeny in Kalimantan originated by triple junction extensional tectonics producing hot spots of Neogene volcanics.

At present orogenic events in most of these occurrences are still in progress.

AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia