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2006 Indian Ocean Earthquake
An earthquake occurred on July 17, 2006 at along a subduction zone off the coast of west and central Java, a large and densely populated island in the Indonesian archipelago. The shock had a moment magnitude of 7.7 and a maximum perceived intensity of IV (''Light'') in Jakarta, the capital and largest city of Indonesia. There were no direct effects of the earthquake's shaking due to its low intensity, and the large loss of life from the event was due to the resulting tsunami, which inundated a portion of the Java coast that had been unaffected by the earlier 2004 Indian Ocean earthquake and tsunami that was off the coast of Sumatra. The July 2006 earthquake was also centered in the Indian Ocean, from the coast of Java, and had a duration of more than three minutes. An abnormally slow rupture at the Sunda Trench and a tsunami that was unusually strong relative to the size of the earthquake were both factors that led to it being categorized as a tsunami earthquake. Seve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time In Indonesia
The Indonesian Archipelago geographically stretches across four time zones from UTC+06:00 in Aceh to UTC+09:00 in Papua. However, the Indonesian government recognises only three time zones in its territory, namely: *Western Indonesia Time (WIB) — seven hours ahead ( UTC+07:00) of the Coordinated Universal Time (UTC); *Central Indonesia Time (WITA) — eight hours ahead ( UTC+08:00) of UTC; *Eastern Indonesia Time (WIT) — nine hours ahead ( UTC+09:00) of UTC. The boundary between the Western and Central time zones was established as a line running north between Java and Bali through the provincial boundaries of West and Central Kalimantan. The border between the Central and Eastern time zones runs north from the eastern tip of Indonesian Timor to the eastern tip of Sulawesi. Daylight saving time (DST) is no longer observed anywhere in Indonesia. Current usage In Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunda Trench
The Sunda Trench, earlier known as and sometimes still indicated as the Java Trench, is an oceanic trench located in the Indian Ocean near Sumatra, formed where the Australian- Capricorn plates subduct under a part of the Eurasian Plate. It is long with a maximum depth of 7,290 metres (23,920 feet). Its maximum depth is the deepest point in the Indian Ocean. The trench stretches from the Lesser Sunda Islands past Java, around the southern coast of Sumatra on to the Andaman Islands, and forms the boundary between Indo-Australian Plate and Eurasian plate (more specifically, Sunda Plate). The trench is considered to be part of the Pacific Ring of Fire as well as one of a ring of oceanic trenches around the northern edges of the Australian Plate. In 2005, scientists found evidence that the 2004 earthquake activity in the area of the Java Trench could lead to further catastrophic shifting within a relatively short period of time, perhaps less than a decade. This threat has resulted i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastic-rebound Theory
__NOTOC__ In geology, the elastic-rebound theory is an explanation for how energy is released during an earthquake. As the Earth's crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. Slowly they deform, until their internal rigidity is exceeded. Then they separate with a rupture along the fault; the sudden movement releases accumulated energy, and the rocks snap back almost to their original shape. The previously solid mass is divided between the two slowly moving plates, the energy released through the surroundings in a seismic wave. Theory After the great 1906 San Francisco earthquake, geophysicist Harry Fielding Reid examined the displacement of the ground surface along the San Andreas Fault in the 50 years before the earthquake.Reid, H.F., ''The Mechanics of the Earthquake, The California Earthquake of April 18, 1906; Report of the State Investigation Commission,'' Vol.2, Carnegie Institution of Washington, Washington, D.C. 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
September 2007 Sumatra Earthquakes
The September 2007 Sumatra earthquakes were a series of megathrust earthquakes that struck the Sunda Trench off the coast of Sumatra, Indonesia, with three of magnitude 7 or greater. A series of tsunami bulletins was issued for the area. The most powerful of the series had a magnitude of 8.5, which makes it in the top 20 of the largest earthquakes ever recorded on a seismograph. Timeline The first earthquake occurred at 11:10:26 UTC (18:10 local time) on 12 September 2007, and was an 8.5 earthquake on the moment magnitude scale. It had a focal depth of 34 km, at , about 130 km southwest of Bengkulu on the southwest coast of Sumatra, Indonesia, and some 600 km west-northwest of Indonesia's capital city, Jakarta. It was followed by several earthquakes of magnitude 5 through 6 along the same fault, west of Sumatra. The second largest earthquake, 7.9 Mw, occurred later the same day at 23:49:04 UTC (06:49:04 local time the following day). It was centred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2005 Nias–Simeulue Earthquake
The 2005 Nias–Simeulue earthquake occurred on 28 March off the west coast of northern Sumatra, Indonesia. At least 915 people were killed, mostly on the island of Nias. The event caused panic in the region, which had already been devastated by the massive tsunami triggered by the 2004 Indian Ocean earthquake, but this earthquake generated a relatively small tsunami that caused limited damage. It was the third most powerful earthquake since 1965 in Indonesia. The earthquake occurred at 16:09:37 UTC (23:09:37 local time) on 28 March 2005. The hypocenter was located below the surface of the Indian Ocean, where subduction is forcing the Indo-Australian Plate to the southwest under the Eurasian Plate's Sunda edge. The area is west of Sibolga, Sumatra, or northwest of Jakarta, approximately halfway between the islands of Nias and Simeulue. Seismic recordings give the earthquake a moment magnitude of about 8.6, and effects were felt as far away as Bangkok, Thailand, over away. Ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Trench
Oceanic trenches are prominent long, narrow topographic depressions of the ocean floor. They are typically wide and below the level of the surrounding oceanic floor, but can be thousands of kilometers in length. There are about of oceanic trenches worldwide, mostly around the Pacific Ocean, but also in the eastern Indian Ocean and a few other locations. The greatest ocean depth measured is in the Challenger Deep of the Mariana Trench, at a depth of below sea level. Oceanic trenches are a feature of the Earth's distinctive plate tectonics. They mark the locations of convergent plate boundaries, along which lithospheric plates move towards each other at rates that vary from a few millimeters to over ten centimeters per year. Oceanic lithosphere moves into trenches at a global rate of about 3 km2/yr. A trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab. Trenches are generally parallel to and about from a vol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere is recycled into the Earth's mantle at convergent boundaries. Where the oceanic lithosphere of a tectonic plate converges with the less dense lithosphere of a second plate, the heavier plate dives beneath the second plate and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with the average rate of convergence being approximately two to eight centimeters per year along most plate boundaries. Subduction is possible because the cold oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle underlying the cold, rigid lithosphere. Once initiated, stable subduction is driven mostly by the negative buoyancy of the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Plate
The Australian Plate is a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when India broke away and began moving north. Australia and Antarctica began rifting and completely separated roughly . The Australian plate later fused with the adjacent Indian Plate beneath the Indian Ocean to form a single Indo-Australian Plate. However, recent studies suggest that the two plates have once again split apart and have been separate plates for at least 3 million years and likely longer. The Australian Plate includes the continent of Australia, including Tasmania, as well as portions of New Guinea, New Zealand and the Indian Ocean basin. Scope The continental crust of this plate covers the whole of Australia, the Gulf of Carpentaria, southern New Guinea, the Arafura Sea, the Coral Sea. The continental crust also includes northwestern N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Boundary
A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more Plate tectonics, lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a plane where many earthquakes occur, called the Wadati–Benioff zone. These collisions happen on scales of millions to tens of millions of years and can lead to volcanism, earthquakes, Orogeny, orogenesis, destruction of lithosphere, and Deformation (geology), deformation. Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere. The geologic features related to convergent boundaries vary depending on crust types. Plate tectonics is driven by convection cells in the mantle. Convection cells are the result of heat generated by the radioactive decay of elements in the mantle escaping to the surface and the return of cool materials from the surfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Types Of Volcanic Eruptions
Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series. There are three different types of eruptions: * Magmatic eruptions are the most well-observed type of eruption. They involve the decompression of gas within magma that propels it forward. * Phreatic eruptions are driven by the superheating of steam due to the close proximity of magma. This type exhibits no magmatic release, instead causing the granulation of existing rock. * Phreatomagmatic eruptions are driven by the direct interaction of magma and water, as opposed to phreatic erup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pangandaran
Pangandaran is a town and district of Pangandaran Regency within the province of West Java, Indonesia. It is located on the southern coast of the island of Java. A well-known surfing beach has made Pangandaran a popular tourist destination. History On 17 July 2006, an undersea earthquake measuring 7.7 on the moment magnitude scale triggered a tsunami which engulfed the resort area and caused destruction as far inland as half a kilometre. Over three hundred people from the town were killed. Tourism Pangandaran is a large fishing village situated on a narrow isthmus with Pangandaran National Park occupying the entire headland. On either side to the east and to the west of Pangandaran village and the National Park isthmus are two beaches of volcanic black sand. The Penanjung Pangandaran nature reserve is nearby on a peninsula connected to the mainland by a narrow neck of land. The isthmus is around 200 m wide. About eighty percent of the nature reserve is secondar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kambangan Island
Nusa Kambangan (also Nusakambangan, Kambangan island, or Nusa Kambangan Island) island is located in Indonesia, separated by a narrow strait from the south coast of Java; the closest port is Cilacap in Central Java province. It known as the place where the fabled ''wijayakusuma'', which translates as the 'flower of victory' in the highest literary register of the Javanese language, grows. The ''wijayakusuma'' can be used to bring a person back from the dead, and the princes of the Sultanate of Mataram and later the Surakarta Sunanate sent to the island for the blooms in order to become kings. Thus the island is also known as ''pulau bunga-bungaan'', the 'island of many flowers'. There is a forest reserve on the island. One of the main cultural events is ''Sedekah Laut'' (sea sacrifice), which is held by the Surakarta Sunanate every Satu Suro (new year) in the Javanese calendar. Since the Dutch colonial period, there have been a number of supermax prisons on the island, some of w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
