List of islands of Indonesia
The islands of Indonesia, also known as the Indonesian archipelago and formerly known as the Indian archipelago, may refer either to the islands comprising the nation-state of Indonesia or to the geographical groups which include its islands. According to the Indonesian Coordinating Ministry for Maritime Affairs, of 17,508 officially listed islands within the territory of the Republic of Indonesia, 16,056 island names have been verified by the United Nations Group of Experts on Geographical Names (UNGEGN) as of July 2017.
1981 Irian Jaya earthquake
Indonesia, one of the most seismically active places in the world, hosts hundreds of islands, many with volcanoes. It is an island arc, composed by a subduction zone (in the Sunda Trench) and islands. Unlike most subduction zones, the Sunda Trench is parallel to the chain of islands to which it corresponds, creating strike-slip faulting. Indonesia itself is surrounded by multiple tectonic plates – namely the Pacific, the Southeast Asia lithospheric, and the Indo-Australian Plates – causing it to be a so-called hotspot for both seismic and volcanic activity. The epicenter was in Papua Province, in the Irian Jaya Province. The orientation and type of faulting is uncertain, due to a poorly constrained focal mechanism but is thought to have been a reverse fault.