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Macquarie Fault Zone
The Macquarie Fault Zone is a major right lateral-moving transform fault along the seafloor of the south Pacific Ocean which runs from New Zealand southwestward to the Macquarie Triple Junction. It is also the tectonic plate boundary between the Indo-Australian Plate to the northwest and the Pacific Plate to the southeast. The Macquarie Fault Zone includes a component of convergence which increases as it approaches the South Island of New Zealand. Many researchers conclude that the fault zone here is an incipient subduction zone, with oblique motion corresponding to the transition from lateral (strike-slip) motion. In the area known as the Puysegur Trench, the Indo-Australian Plate appears to be starting to sink beneath the Pacific Plate, the reverse of what is occurring off of New Zealand's North Island (see Kermadec-Tonga Subduction Zone). A major geographic feature which runs along the Macquarie Fault Zone is known as the Macquarie Ridge. This ridge represents both the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macquarie
Macquarie may refer to: People * Lachlan Macquarie, Governor of the British colony of New South Wales from 1810 to 1821. * Elizabeth Macquarie Campbell, Lachlan Macquarie's second wife Locations * Division of Macquarie, an electoral district in the Australian House of Representatives in New South Wales * Lake Macquarie (New South Wales), a lake in New South Wales, Australia ** City of Lake Macquarie, a local government area surrounding Lake Macquarie * Macquarie, Australian Capital Territory, a suburb of Canberra, Australia * Macquarie County, one of the 141 Cadastral divisions of New South Wales, Australia * Macquarie Fields, New South Wales, a suburb of Sydney, Australia * Macquarie Island, in the Southern Ocean * Macquarie Park, New South Wales, a suburb of Sydney, Australia ** Macquarie Centre, a regional sized shopping centre located in Macquarie Park * Macquarie River, an inland river in New South Wales, Australia ** Macquarie Marshes Nature Reserve * Macquarie Street, Sydney, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kermadec-Tonga Subduction Zone
The Kermadec-Tonga subduction zone is a convergent plate boundary that stretches from the North Island of New Zealand northward. The formation of the Kermadec and Tonga Plates started about 4–5 million years ago. Today, the eastern boundary of the Tonga Plate is one of the fastest subduction zones, with a rate up to 24 cm/yr. The trench formed between the Kermadec-Tonga and Pacific Plates is also home to the second deepest trench in the world, at about 10,800 m, as well as the longest chain of submerged volcanoes. Geological setting The Kermadec-Tonga subduction zone is a convergent plate boundary that stretches from the southwest of the Kermadec Plate (northeast of New Zealand) to the northwest tip of the Tonga Plate, with the Pacific Plate being subducted under both the Kermadec and Tonga Plates. The Kermadec and Tonga Plates are micro oceanic plates in the Pacific Ocean, bounded by the Australian and Pacific Plates to the west and east respectively. The Kermadec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Faults Of Australia
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] |
Seismic Faults Of New Zealand
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] |
Zealandia
Zealandia (pronounced ), also known as (Māori) or Tasmantis, is an almost entirely submerged mass of continental crust that subsided after breaking away from Gondwanaland 83–79 million years ago.Gurnis, M., Hall, C.E., and Lavier, L.L., 2004, Evolving force balance during incipient subduction: Geochemistry, Geophysics, Geosystems, v. 5, Q07001, https://doi.org/10.01029/02003GC000681 It has been described variously as a submerged continent, a continental fragment (or microcontinent), and a continent. The name and concept for Zealandia was proposed by Bruce Luyendyk in 1995, and satellite imagery shows it to be almost the size of Australia. A 2021 study suggests Zealandia is 1 billion years old, about twice as old as geologists previously thought. By approximately 23 million years ago the landmass may have been completely submerged. Today, most of the landmass (94%) remains submerged beneath the Pacific Ocean. New Zealand is the largest part of Zealandia that is above sea ... [...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] |
Alpine Fault
The Alpine Fault is a geological fault that runs almost the entire length of New Zealand's South Island (c. 480 km) and forms the boundary between the Pacific Plate and the Indo-Australian Plate. The Southern Alps have been uplifted on the fault over the last 12 million years in a series of earthquakes. However, most of the motion on the fault is strike-slip (side to side), with the Tasman district and West Coast moving North and Canterbury and Otago moving South. The average slip rates in the fault's central region are about 38 mm a year, very fast by global standards. The last major earthquake on the Alpine Fault was in c. 1717 AD, and the probability of another one occurring within the next 50 years is estimated at about 75 percent. Geographic extent and plate motion ThPacific Plate and Indo-Australian Plate boundaryforms the Macquarie Fault Zone in the Puysegur Trench off the southwestern corner of the South Island and comes onshore as the Alpine Fault just nort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lachlan Macquarie
Major-general (United Kingdom), Major General Lachlan Macquarie, Companion of the Order of the Bath, CB (; gd, Lachann MacGuaire; 31 January 1762 – 1 July 1824) was a British Army officer and colonial administrator from Scotland. Macquarie served as the fifth Governor of New South Wales from 1810 to 1821, and had a leading role in the social, economic, and architectural development of the colony. He is considered by historians to have had a crucial influence on the transition of New South Wales from a penal colony to a free settlement and therefore to have played a major role in the shaping of Australian society in the early nineteenth century. Early life Lachlan Macquarie was born on the island of Ulva off the coast of the Isle of Mull in the Inner Hebrides, a chain of islands off the West Coast of Scotland. His father, Lachlan senior, worked as a carpenter and miller, and was a cousin of a Clan MacQuarrie chieftain. His mother, Margaret, was the sister of the influential Cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macquarie Island
Macquarie Island is an island in the southwestern Pacific Ocean, about halfway between New Zealand and Antarctica. Regionally part of Oceania and politically a part of Tasmania, Australia, since 1900, it became a Tasmanian State Reserve in 1978 and was inscribed as a UNESCO World Heritage Site in 1997. It was a part of Esperance Municipality until 1993, when the municipality was merged with other municipalities to form Huon Valley Council. The island is home to the entire royal penguin population during their annual nesting season. Ecologically, the island is part of the Antipodes Subantarctic Islands tundra ecoregion. Since 1948, the Australian Antarctic Division (AAD) has maintained a permanent base, the Macquarie Island Station, on the isthmus at the northern end of the island at the foot of Wireless Hill. The population of the base, constituting the island's only human inhabitants, usually varies from 20 to 40 people over the year. A heliport is located nearby. In Septemb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puysegur Trench
The deepStern, Robert J. (2004)Subduction initiation: spontaneous and induced Earth and Planetary Science Letters 226, 275–292. . Puysegur Trench is a deep cleft in the floor of the south Tasman Sea formed by the subduction of the Indo-Australian Plate under the Pacific Plate to the south of New Zealand. Immediately to its east lies a ridge, a northern extension of the Macquarie Ridge, which separates the Puysegur Trench from the Solander Trough. To the west is the expanse of the Tasman Basin, which stretches most of the distance to Australia. To the north of the trench lies the Fiordland Basin, which can be considered an extension of the trench. The Puysegur Trench mirrors the Kermadec Trench and Tonga Trench north of New Zealand. The Puysegur Trench stretches for over 800 kilometres south from the southwesternmost point of the South Island's coast, its southernmost extent being 400 kilometres due west of the Auckland Islands. It is named after Puysegur Point. Earthqua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transform Fault
A transform fault or transform boundary, is a fault along a plate boundary where the motion is predominantly horizontal. It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone. A transform fault is a special case of a ''strike-slip fault'' that also forms a plate boundary. Most such faults are found in oceanic crust, where they accommodate the lateral offset between segments of divergent boundaries, forming a zigzag pattern. This is a result of oblique seafloor spreading where the direction of motion is not perpendicular to the trend of the overall divergent boundary. A smaller number of such faults are found on land, although these are generally better-known, such as the San Andreas Fault and North Anatolian Fault. Nomenclature Transform boundaries are also known as conservative plate boundaries because they involve no addition or loss of lithosphere at the Earth's surface. Background Geophysicist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction Zone
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 dens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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