Great Sumatran fault
Encyclopedia
The Indonesia
n island of Sumatra
is located in a highly seismic area of the world. In addition to the subduction zone
and the associated Sunda Arc
off the west coast of the island, Sumatra also has a large strike-slip fault, the so-called Great Sumatran Fault, running the entire length of the island. This fault zone accommodates most of the strike-slip motion associated with the oblique convergence between the Indo-Australian
and Eurasian
plates
. The fault ends in the north just below the city of Banda Aceh
, which was devastated in the 2004 Indian Ocean earthquake
. After the December 2004 earthquake, pressure on the Great Sumatran Fault has increased tremendously, especially in the north.
Although an earthquake
on this fault will not create a tsunami
, it will still probably have disastrous consequences, due to its proximity to major population centers.
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
n island of Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
is located in a highly seismic area of the world. In addition to the subduction zone
Subduction
In geology, subduction is the process that takes place at convergent boundaries by which one tectonic plate moves under another tectonic plate, sinking into the Earth's mantle, as the plates converge. These 3D regions of mantle downwellings are known as "Subduction Zones"...
and the associated Sunda Arc
Sunda Arc
The Sunda Arc is a volcanic arc that has produced the islands of Sumatra and Java, the Sunda Strait and the Lesser Sunda Islands. A chain of volcanoes forms the topographic spine of these islands...
off the west coast of the island, Sumatra also has a large strike-slip fault, the so-called Great Sumatran Fault, running the entire length of the island. This fault zone accommodates most of the strike-slip motion associated with the oblique convergence between the Indo-Australian
Indo-Australian Plate
The Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and surrounding ocean, and extends northwest to include the Indian subcontinent and adjacent waters...
and Eurasian
Eurasian Plate
The Eurasian Plate is a tectonic plate which includes most of the continent of Eurasia , with the notable exceptions of the Indian subcontinent, the Arabian subcontinent, and the area east of the Chersky Range in East Siberia...
plates
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...
. The fault ends in the north just below the city of Banda Aceh
Banda Aceh
Banda Aceh is the provincial capital and largest city in the province of Aceh, Indonesia, located on the island of Sumatra, with an elevation of 35 meters. The city regency covers an area of 64 square kilometres and according to the 2000 census had a population of 219,070 people...
, which was devastated in the 2004 Indian Ocean earthquake
2004 Indian Ocean earthquake
The 2004 Indian Ocean earthquake was an undersea megathrust earthquake that occurred at 00:58:53 UTC on Sunday, December 26, 2004, with an epicentre off the west coast of Sumatra, Indonesia. The quake itself is known by the scientific community as the Sumatra-Andaman earthquake...
. After the December 2004 earthquake, pressure on the Great Sumatran Fault has increased tremendously, especially in the north.
Although an earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
on this fault will not create a tsunami
Tsunami
A tsunami is a series of water waves caused by the displacement of a large volume of a body of water, typically an ocean or a large lake...
, it will still probably have disastrous consequences, due to its proximity to major population centers.