Lesser Sunda Islands

The Lesser Sunda Islands or Nusa Tenggara ("Southeastern Islands") are a group of islands in Maritime Southeast Asia, north of Australia. Together with the Greater Sunda Islands to the west they make up the Sunda Islands. The islands are part of a volcanic arc, the Sunda Arc, formed by subduction along the Sunda Trench in the Java Sea.

The main Lesser Sunda Islands are, from west to east: Bali, Lombok, Sumbawa, Flores, Sumba, Timor, Alor archipelago, Barat Daya Islands, and Tanimbar Islands.

Administration

The Lesser Sundas comprise many islands, most of which are part of Indonesia and are administered as the provinces of Bali, West Nusa Tenggara, East Nusa Tenggara and southern part of Maluku.

The eastern half of Timor is part of East Timor.

Geology

The Lesser Sunda Islands consist of two geologically distinct archipelagos. The northern archipelago, which includes Bali, Lombok, Sumbawa, Flores and Wetar, is volcanic in origin, a number of these, like Mount Rinjani on Lombok, are still active while others, such as Kelimutu on Flores with its three multi-coloured crater lakes, are extinct. The northern archipelago began to be formed during the Pliocene, about 15 million years ago, as a result of the collision between the Australian and the Asian plates. The islands of the southern archipelago, including Sumba, Timor and Babar, are non-volcanic and appear to belong to the Australian plate. The geology and ecology of the northern archipelago share a similar history, characteristics and processes with the southern Maluku Islands, which continue the same island arc to the east.