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Flores Back Arc Thrust Fault
Flores Back Arc Thrust Fault is a major system of west-east trending thrust faults that extend eastwards from west of Lombok towards the islands of Sumbawa, Flores, and Alor, with a total length of at least 800 km. The thrust faults are south- dipping and lie within the back arc region of the Sunda-Banda Arc, which is related to the ongoing subduction of the Australian Plate beneath the Sunda and Banda Sea Plates. The thrust fault system developed as a result of the onset of continental collision as continental crust of the Australian Plate reached the Sunda Trench. The eastern part of the fault system is also known as the Wetar thrust. Above the main thrust fault are a series of imbricate (overlapping) thrust faults. These imbricate thrust faults are shallower in depth than the main Flores thrust. Although the exact thrust faults have not been established, these faults were thought to be responsible for the 2018 Lombok earthquake 2018 Lombok earthquake may refer to the following ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular ''klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is referred to as a ''blind thrust'' fault. Because of the lack of surface evidence, blind thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunda Plate
The Sunda Plate is a minor tectonic plate straddling the Equator in the Eastern Hemisphere on which the majority of Southeast Asia is located. The Sunda Plate was formerly considered a part of the Eurasian Plate, but the GPS measurements have confirmed its independent movement at 10 mm/yr eastward relative to Eurasia. Extent The Sunda Plate includes the South China Sea, the Andaman Sea, southern parts of Vietnam and Thailand along with Malaysia and the islands of Borneo, Sumatra, Java, and part of Sulawesi in Indonesia, plus the south-western Philippines islands of Palawan and the Sulu Archipelago. The Sunda is bounded in the east by the Philippine Mobile Belt, Molucca Sea Collision Zone, Molucca Sea Plate, Banda Sea Plate and Timor Plate; to the south and west by the Australian Plate; and to the north by the Burma Plate, Eurasian Plate; and Yangtze Plate. The Indo-Australian Plate dips beneath the Sunda Plate along the Sunda Trench, which generates frequent earthq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Indonesia
This is a brief summary of the geology of Indonesia. Indonesia is located between two major tectonic plates, the Australian Plate and the Eurasian Plate. Tectonics The tectonics of Indonesia are very complex, as it is a meeting point of several tectonic plates. Indonesia is located between two continental plates: the Australian Plate (Sahul Shelf) and the Eurasian Plate (Sunda Shelf); and between two oceanic plates: the Pacific Plate and the Philippine Sea Plate. The subduction of the Indian Plate beneath the Eurasian Plate formed the volcanic arc in western Indonesia, one of the most seismically active areas on the planet with a long history of powerful eruptions and earthquakes. This chain of active volcanoes formed Sumatra, Java, Bali, and the Lesser Sunda Islands, most of which, particularly Java and Bali, emerged within the last 2–3 million years. The Pacific and Australian plate movements controlled the tectonics of the eastern portion of Indonesia. Structural g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Faults Of Southeast Asia
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial, oceanic, atmospheric, and artificial processes such as explosions. A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of Earth motion as a function of time is called a seismogram. A seismologist is a scientist who does research in seismology. History Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (c. 585 BCE), Anaximenes of Miletus (c. 550 BCE), Aristotle (c. 340 BCE), and Zhan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2018 Lombok Earthquake
2018 Lombok earthquake may refer to the following 5 thrust type earthquakes, with epicentres north of Rinjani volcano, that caused significant damage and deaths: *July 2018 Lombok earthquake ( and : 6.4, a foreshock) *5 August 2018 Lombok earthquake (Mw: 6.9, : 7.0, the mainshock) *9 August 2018 (: 5.9 aftershock, 6 deaths) *18 August 2018 23:10pm local time Lombok earthquakes (: 6.4 aftershock, 2 dead) * 19 August 2018 Lombok earthquake ( 6.9 new earthquake, different fault.) See also * 2018 Indonesia earthquakes * List of earthquakes in Indonesia, including Lombok * List of earthquakes in 2018 This is a list of earthquakes in 2018. Only earthquakes of magnitude 6 or above are included, unless they result in damage and/or casualties, or are notable for other reasons. All dates are listed according to UTC time. Maximum intensities are ... {{Set index article 2018 disasters in Indonesia 2018 earthquakes Lombok ... [...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] |
Continental Crust
Continental crust is the layer of igneous, sedimentary, and metamorphic rocks that forms the geological continents and the areas of shallow seabed close to their shores, known as continental shelves. This layer is sometimes called ''sial'' because its bulk composition is richer in aluminium silicates (Al-Si) and has a lower density compared to the oceanic crust, called ''sima'' which is richer in magnesium silicate (Mg-Si) minerals. Changes in seismic wave velocities have shown that at a certain depth (the Conrad discontinuity), there is a reasonably sharp contrast between the more felsic upper continental crust and the lower continental crust, which is more mafic in character. The continental crust consists of various layers, with a bulk composition that is intermediate (SiO2 wt% = 60.6). The average density of continental crust is about , less dense than the ultramafic material that makes up the mantle, which has a density of around . Continental crust is also less dense ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Collision
In geology, continental collision is a phenomenon of plate tectonics that occurs at convergent boundaries. Continental collision is a variation on the fundamental process of subduction, whereby the subduction zone is destroyed, mountains produced, and two continents sutured together. Continental collision is only known to occur on Earth. Continental collision is not an instantaneous event, but may take several tens of millions of years before the faulting and folding caused by collisions stops. The collision between India and Asia has been going on for about 50 million years already and shows no signs of abating. Collision between East and West Gondwana to form the East African Orogen took about 100 million years from beginning (610 Ma) to end (510 Ma). The collision between Gondwana and Laurasia to form Pangea occurred in a relatively brief interval, about 50 million years long. Subduction zone: the collision site The process begins as two conti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banda Sea Plate
The Banda Sea Plate is a minor tectonic plate underlying the Banda Sea in southeast Asia. This plate also carries a portion of Sulawesi Island, the entire Seram Island, and the Banda Islands. Clockwise from the east it is bounded by the Bird's Head Plate of western New Guinea, Australian Plate, Timor Plate, Sunda Plate, and the Molucca Sea Collision Zone. The western border is a convergent boundary largely responsible for the mountains in western Sulawesi, subduction zones also exist on the eastern border near Seram and the southern border with the Timor Plate. A small rift is located in the middle of Sulawesi. It is a very seismically active area home to many volcanoes and the site of many large earthquakes, the largest of which was the 1938 Banda Sea earthquake which measured around 8.4 on the moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's mag ... [...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] |
Lombok
Lombok is an island in West Nusa Tenggara province, Indonesia. It forms part of the chain of the Lesser Sunda Islands, with the Lombok Strait separating it from Bali to the west and the Alas Strait between it and Sumbawa to the east. It is roughly circular, with a "tail" ( Sekotong Peninsula) to the southwest, about across and a total area of about including smaller offshore islands. The provincial capital and largest city on the island is Mataram. Orang Lombok is some what similar in size and density, and shares some cultural heritage with the neighboring island of Bali to the west. However, it is administratively part of West Nusa Tenggara, along with the larger and more sparsely populated island of Sumbawa to the east. Lombok is surrounded by a number of smaller islands locally called Gili. The island was home to some 3,168,692 Indonesians as recorded in the decennial 2010 censusBiro Pusat Statistik, Jakarta, 2011. and 3,758,631 in the 2020 Census;Badan Pusat Statistik, ... [...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] |
