The search for the missing Malaysia Airlines flight MH370, which was focused earlier on the South China Sea, has been expanded to the Malacca Strait and the Andaman Sea. The Boeing 777-200 jetliner, which was carrying 239, was on its way from Kuala Lumpur to Beijing on March 8 when it fell off radar screens in the South China Sea. Malaysian officials now believe it may have turned around, and search teams are also scouring the waters off the west coast of Malaysia.
Here are 10 key facts about the Malacca Strait and the Andaman Sea.
Malacca Strait (or Strait of Malacca)
1. The 800km-long waterway connects the Andaman Sea with the South China Sea. It is about 65km-wide in the south, broadening northwards to some 250km. At its narrowest point, it is only 2.7km wide. In its southern part, its depth is rarely beyond 36m and usually only 27m. In the north-west, it deepens gradually to about 200m as it merges with the Andaman basin. Numerous islets, some fringed by reefs and sand ridges, hinder passage at the southern entrance to the strait.
2. The narrow stretch of water is one of the most important shipping lanes in the world, as it is the shortest sea route between the growing markets of Asia and the Middle East and beyond. More than 50,000 merchant ships ply its waters every year.
3. The strait is also critical to global energy security. About one-third of all seaborne oil - 15 million barrels per day of oil and petroleum products - was transported through the strait at the end of 2011. But the United States Energy Information Administration says it is one of the world’s two "most strategic chokepoints" for oil trade, along with the Strait of Hormuz in the Persian Gulf. The Malacca Strait's narrowest point, at only 2.7km wide, not only creates a natural bottleneck, but also potential for collisions, grounding or oil spills.
4. The congested waterway is becoming increasingly important strategically to Beijing, with nearly 80 per cent of China's crude oil imports passing through it from the Middle East and Africa in 2011.
5. Piracy has been a problem in the Malacca Strait, but there has been a steep decline in pirate attacks and armed robbery in recent years, partly as a result of intensified surveillance and coordinated patrols by littoral states since 2005. There was one pirate attack in the Malacca Strait from January to June in 2013, one in 2012 and none in 2011, according to the International Maritime Bureau.
1. The Andaman Sea, which lies to the north-west of the Malacca Strait, is 798,000 sq km big. It is 1,200km long and 650km wide. Its average depth is about 1,000m. The northern and eastern parts are shallower than 180m due to the silt deposited by the Irrawaddy River, which flows into the Andaman Sea from Myanmar. The depth of some parts of the sea can exceed 4,000m. The sea floor is covered with pebbles, gravel and sand.
2. The Andaman Sea is the most important sea link between Myanmar and other countries, and is also a major shipping route between India and China, via the Malacca Strait.
3. It has traditionally been used for fishing. But overfishing, caused in large by improved technology and rapid industrialisation in Thailand, the third largest seafood exporter in the world, has led to a drop in the catch. The non-profit British-based Environmental Justice Foundation said that in 2011, the catch per hour in the Andaman Sea dropped to 41kg, down from around 240kg in 1961.
4. The Andaman Sea takes its name from the Andaman Islands and its coral-reef fringed islands are popular tourist destinations. World-famed beach resorts such as Phuket and the Phi Phi islands are located here.
5. The sea lies in a seismic zone. On Dec 26, 2004, a 9.1-magnitude earthquake off the coast of Sumatra triggered a massive tsunami that killed more than 220,000 people in a dozen countries and wipes out coastal towns in countries bordering the Andaman Sea.
Sources: Reuters, Encyclopaedia Britannica, United States Energy Information Administration