Australia-Indonesia border

The Australia–Indonesia border is a maritime boundary running west from the two countries' tripoint maritime boundary with Papua New Guinea in the western entrance to the Torres Straits through the Arafura Sea and Timor Sea and terminating in the Indian Ocean. The boundary is, however, broken by the "Timor Gap", where Australian and East Timorese territorial waters meet and where the two countries have overlapping claims to the seabed.

Australia and Indonesia also share a common maritime border in the Indian Ocean between Australia's oversea territory of Christmas Island and the Indonesian island of Java.

An interesting characteristic of the maritime border between the two countries is the separation of the ownership of the seabed (essentially the continental shelf) and ownership of the water column (exclusive economic zone), each with their own boundary. Ownership over the seabed gives the country rights over all mineral resources in the seabed while ownership of the water column allows a country over fishing rights and other resources of the water in the specified area. The treaty establishing this and the western parts of the border as well as that between Christmas Island and Java, signed in 1997, has however not been ratified and is not in force. This was because the independence of East Timor required amendments to the 1997 treaty and agreement over them by the two parties is still pending.

The boundary is separated into three segments, with the first two broken by the Timor Gap. The first is between the Australia – Indonesia – Papua New Guinea tripoint at 10° 50' S, 139° 12' E, and the point whether the territorial waters of the two countries touch the eastern limits of the territorial waters claimed by East Timor at 9° 28' S, 127° 56' E. The second segment runs westward from the point where the territorial waters of the two countries touch the western limits of East Timor's territorial waters claim at 10° 28' S, 126° 00' E, to 13° 05' 27.0" S, 118° 10' 08.9" E in the Indian Ocean. The third is between the Australian external territory of Christmas Island and the Indonesia island of Java, in the Indian Ocean.

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Wikipedia