The Timor Sea (Laut Timor; Portuguese: Mar Timor) is a sea bounded to the north by the island of Timor, to the east by the Arafura Sea, to the south by Australia and to the west by the Indian Ocean.
The waters to the east are known as the Arafura Sea. The Timor Sea is adjacent to two substantial inlets on the north Australian coast, the Joseph Bonaparte Gulf and the Van Diemen Gulf. The Australian city of Darwin is the only large city to adjoin the sea.
The sea is about 480 km (300 statute miles) wide, covering an area of about 610,000 km². (235,000 square miles). Its deepest point is the Timor Trough, which is the south-eastern extension of the Java Trench, located in the northern part of the sea, which reaches a depth of 3,300 m (10,800 ft). The remainder of the sea is much shallower, much of it averaging less than 200 m (650 ft) deep, as it overlies the Sahul Shelf, part of the Australian continental shelf.
Many tropical storms and cyclones originate or pass through the Timor Sea. In February 2005, Tropical Cyclone Vivienne disrupted oil and gas production facilities in the area, and the next month, Severe Tropical Cyclone Willy interrupted production. . The petroleum production facilities are designed to withstand the effects of cyclones, although as a safety precaution production is usually reduced or temporarily halted and workers evacuated by helicopter to the mainland - usually to Darwin or Dili.
Reefs and islands
A number of significant islands are located in the sea, notably Melville Island, part of the Tiwi Islands, off Australia and the Australian-governed Ashmore and Cartier Islands. It is thought that early humans reached Australia by "island-hopping" across the Timor Sea.
Scott and Seringapatam Reefs formed in the area and to the west on the same underwater platform is the Rowley Shoals.
Beneath the Timor Sea lie considerable reserves of oil
. A number of offshore petroleum projects are in operation and there is considerable exploration activity either underway and numerous projects proposed for the future.
The largest petroleum project in operation in the Timor Sea is the Bayu-Undan project operated by ConocoPhillips
. The Bayu-Undan field is located approximately 500km north-west of Darwin
. Production commenced in 2004 as a gas recycle project - with liquids (condensate, propane and butane) being stripped from the raw production stream and exported. Gas was pumped back down into the reservoir. At around the same time, construction commenced on a 500km subsea natural gas pipeline
connecting the Bayu-Undan processing facility to a liquefied natural gas
plant situated at Wickham Point in Darwin
harbour. Since the completion of the pipeline and the Darwin LNG plant in 2006, gas produced offshore at Bayu-Undan is now transported to the Darwin plant where it is converted into a liquid and transported to Japan
under long-term sales contracts.
The Greater Sunrise gas field
, discovered in 1974, is one of the largest in the area and is expected to earn East Timor several billion dollars in royalty revenues.
AED Oil owns the large oil project at Puffin oilfield and Woodside Petroleum is producing oil at the Laminaria oilfield.
Since discovery of petroleum in the Timor Sea in the 1970s, there have been disputes surrounding rights to ownership and exploitation of the resources situated in a part of the Timor Sea known as the Timor Gap
, which is the area of the Timor Sea which lies outside the territorial boundaries of the nations to the north and south of the Timor Sea. These diagreements initially involved Australia and Indonesia, although a resolution was eventually reached in the form of the Timor Gap Treaty
. After declaration of East Timor's nationhood in 1999, the terms of the Timor Gap Treaty were abandoned and negotiations commenced between Australia and East Timor, culminating in the Timor Sea Treaty
Australia's territorial claim extends to the bathymetric axis (the line of greatest sea-bed depth) at the Timor Trough. It overlaps East Timor's own territorial claim, which follows the former colonial power Portugal in claiming that the dividing line should be midway between the two countries.
Timor Sea Treaty
The Timor Sea Treaty
, which was signed on the 20 May 2002, led to the establishment of the Timor Sea Designated Authority (TSDA). This organisation is responsible for the administration of all petroleum-related activities in a part of the Timor Sea known as the Joint Petroleum Development Area (JPDA). Under the terms of the treaty, royalties on petroleum production in the JPDA are split in a 90:10 ratio between East Timor
World War II
During the 1940s the Japanese navy
conducted air raids on Australia
from ships in the Timor Sea. On the 19 February 1942 the Japanese aircraft carrier Kaga
with other vessels, launched air strikes
against Darwin, Australia
, sinking nine ships, including the USS Peary
. This bombing marked the beginning of the Battle of Timor
in the Pacific theatre
of World War II