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Trough (geology)
In geology, a trough is a linear structural depression that extends laterally over a distance. Although it is less steep than a trench, a trough can be a narrow basin or a geologic rift. These features often form at the rim of tectonic plates. There are various oceanic troughs on the ocean floors. Examples of oceanic troughs * Benue Trough * Cayman Trough * Kings Trough * Hesperides Trough * Nankai Trough * Northumberland Trough * Okinawa Trough in the East China Sea * Rockall Trough and others along the rift of the mid-oceanic ridge * Salton Trough The Salton Trough is an active tectonic pull-apart basin, or graben. It lies within the Imperial, Riverside, and San Diego counties of southeastern California, United States and extends south of the Mexico–United States border into the sta ... * South Shetland Trough * Suakin TroughDinwiddie, Robert et al. (2008) ''Ocean: The World's Last Wilderness Revealed'', London, Dorling Kindersley, page 452. in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cayman Trough
__NOTOC__ The Cayman Trough (also known as the Cayman Trench, Bartlett Deep and Bartlett Trough) is a complex transform fault zone pull-apart basin which contains a small spreading ridge, the Mid-Cayman Rise, on the floor of the western Caribbean Sea between Jamaica and the Cayman Islands. It is the deepest point in the Caribbean Sea and forms part of the tectonic boundary between the North American Plate and the Caribbean Plate. It extends from the Windward Passage, going south of the Sierra Maestra of Cuba toward Guatemala. The transform fault continues onshore as the Polochic-Motagua fault system, which consists of the Polochic and Motagua faults. This system continues on until the Chiapas massif where it is part of the diffuse triple junction of the North American, Caribbean and Cocos plates. The relatively narrow trough trends east-northeast to west-southwest and has a maximum depth of . Within the trough is a slowly spreading north–south ridge which may be the result ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nankai Trough
The is a submarine trough located south of the Nankaidō region of Japan's island of Honshu, extending approximately offshore. The underlying fault, the ''Nankai megathrust,'' is the source of the devastating Nankai megathrust earthquakes, while the trough itself is potentially a major source of hydrocarbon fuel, in the form of methane clathrate. In plate tectonics, the Nankai Trough marks a subduction zone that is caused by subduction of the Philippine Sea Plate beneath Japan, part of the Eurasian plate (Kanda et al., 2004). This plate boundary would be an oceanic trench except for a high flux of sediments that fills the trench. Within the Nankai Trough there is a large amount of deformed trench sediments (Ike, 2004), making one of Earth's best examples of accretionary prism. Furthermore, seismic reflection studies have revealed the presence of basement highs that are interpreted as seamounts that are covered in sediments (Ike, 2004). The northern part of the trough is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Basin
In hydrology, an oceanic basin (or ocean basin) is anywhere on Earth that is covered by seawater. Geologically, ocean basins are large geologic basins that are below sea level. Most commonly the ocean is divided into basins following the continents distribution: the North and South Atlantic (together approximately 75 million km2/ 29 million mi2), North and South Pacific (together approximately 155 million km2/ 59 million mi2), Indian Ocean (68 million km2/ 26 million mi2) and Arctic Ocean (14 million km2/ 5.4 million mi2). Also recognized is the Southern Ocean (20 million km2/ 7 million mi2). All ocean basins collectively cover 71% of the Earth's surface, and together they contain almost 97% of all water on the planet. They have an average depth of almost 4 km (about 2.5 miles). Definitions of boundaries Boundaries based on continents ''"Limits of Oceans and Seas"'',International Hydrographic Organization (IHO), (1953): Limits of Oceans and Seas, Interna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walker Lane
The Walker Lane is a geologic trough roughly aligned with the California/Nevada border southward to where Death Valley intersects the Garlock Fault, a major left lateral, or sinistral, strike-slip fault. The north-northwest end of the Walker Lane is between Pyramid Lake in Nevada and California's Lassen Peak where the Honey Lake Fault Zone, the Warm Springs Valley Fault, and the Pyramid Lake Fault Zone meet the transverse tectonic zone forming the southern boundary of the Modoc Plateau and Columbia Plateau provinces. The Walker Lane takes up 15 to 25 percent of the boundary motion between the Pacific Plate and the North American Plate, the other 75 percent being taken up by the San Andreas Fault system to the west. The Walker Lane may represent an incipient major transform fault zone which could replace the San Andreas as the plate boundary in the future. The Walker Lane deformation belt also accommodates nearly 12 mm/yr of dextral shear between the Sierra Nevada– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timor Trough
The Timor Trough is an oceanic trough that is a continuation of the Sunda Trench (Java Trench) that marks the boundary between the Indo-Australian Plate and the Timor Plate. It is separated from the Sunda Trench by a sag near Sumba Island at the Scott Plateau and the North Australian Basin, and on the other end becomes the Tanimbar Trough southeast of the Tanimbar Islands, continuing on to the Aru Trough east of the Kai Islands near the Bird's Head Peninsula on New Guinea. Lining the north of the trough are numerous islands, of which Timor is the largest. Further west are the Weber Basin and the Banda Trench. Oil and natural gas have been found in the Bonaparte Basin The Bonaparte Basin is a sedimentary basin in Western Australia and the Northern Territory of Australia. Its total area is approximately , most of which is offshore. The sedimentary basin emerges at the Joseph Bonaparte Gulf and extends int ... south of the trough and the region is geologically active with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Shetland Trough
The South Shetland Trough is an undersea trough located north of the South Shetland Islands. It is the remnant of a subduction zone where the defunct Phoenix Plate, now part of the Antarctic Plate, subducted under the Antarctic Peninsula The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctic ... and the South Shetland Islands. References Oceanic basins of the Southern Ocean Subduction zones {{marine-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salton Trough
The Salton Trough is an active tectonic pull-apart basin, or graben. It lies within the Imperial, Riverside, and San Diego counties of southeastern California, United States and extends south of the Mexico–United States border into the state of Baja California, Mexico. The northwestern end of the trough starts at the San Gorgonio Pass in Riverside County, and extends southeast to the Gulf of California. Major geographical features located in the trough include the Coachella Valley, the Salton Sea, and the Imperial Valley, in the United States, and the western side of the Mexicali Valley, and the Colorado River Delta in Mexico. The Salton Trough is a result of crustal stretching and sinking caused by the combined actions of the San Andreas Fault and the East Pacific Rise, particularly the Gulf of California Rift Zone (GCRZ), the northernmost portion of the East Pacific Rise. The GCRZ and the San Andreas Fault both terminate near the south end of the Salton Sea, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mid-oceanic Ridge
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about and rises about above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a divergent plate boundary. The rate of seafloor spreading determines the morphology of the crest of the mid-ocean ridge and its width in an ocean basin. The production of new seafloor and oceanic lithosphere results from mantle upwelling in response to plate separation. The melt rises as magma at the linear weakness between the separating plates, and emerges as lava, creating new oceanic crust and lithosphere upon cooling. The first discovered mid-ocean ridge was the Mid-Atlantic Ridge, which is a spreading center that bisects the North and South Atlantic basins; hence the origin of the name 'mid-ocean ridge'. Most oceanic spreading centers are not in the middle of their hosting ocean basis but regardless, are traditionally called mid-ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Okinawa Trough
The (also called , literally China-Ryukyu Border Trough ) is a seabed feature of the East China Sea. It is an active, initial back-arc rifting basin which has formed behind the Ryukyu arc-trench system in the West Pacific. It developed where the Philippine Sea Plate is subducting under the Eurasia Plate. Description It is a back-arc basin formed by extension within the continental lithosphere behind the far deeper Ryukyu Trench-arc system. The thickness of the crust in the northern Okinawa Trough is 30 km, thinning to 10 km in the southern Okinawa Trough. It has a large section more than deep and a maximum depth of . The Okinawa Trough still in an early stage of evolving from arc type to back-arc activity, and features volcanoes such as the Yonaguni Knoll IV. Implications for the China–Japan maritime boundary Interpretations The existence of the Okinawa Trough complicates descriptive issues in the East China Sea.Ji, Guoxing. (1995) "Maritime Jurisdiction in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northumberland Trough
The Northumberland Trough, also known as the Northumberland Basin, is an element of the structural geology of northern England, the origin of which dates back to the Carboniferous period when a block and basin province was established throughout the Pennine region. The trough is an ENE-WSW aligned half-graben, an asymmetric depositional basin. It is defined to the south by the Stublick and Ninety Fathom faults, which separate the trough from the Alston Block. To the north, where its depth is least, the trough's boundary with the Cheviot Block is less well-defined; nevertheless, the south-easterly down-throwing Featherwood and Alwinton faults can be identified along this margin. To the west, the trough is continuous with the Solway Basin. The surrounding blocks are buoyed up by granite batholiths maintaining these regions of the upper crust as areas of raised relief.British Geological Survey. 1996, ''Tectonic Map of Britain, Ireland & adjacent areas'', Pharaoh et al. 1:150 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperides Trough
In Greek mythology, the Hesperides (; , ) are the nymphs of evening and golden light of sunsets, who were the "Daughters of the Evening" or "Nymphs of the West". They were also called the Atlantides () from their reputed father, the Titan Atlas.Diodorus Siculus. ''Library4.27.2' Etymology The name means ''originating from Hesperos'' (evening). ''Hesperos'', or ''Vesper'' in Latin, is the origin of the name Hesperus, the evening star (i.e. the planet Venus) as well as having a shared root with the English word "west". Mythology The nymphs of the evening Ordinarily, the Hesperides number three, like the other Greek triads (the Three Graces and the Three Fates). "Since the Hesperides themselves are mere symbols of the gifts the apples embody, they cannot be actors in a human drama. Their abstract, interchangeable names are a symptom of their impersonality", classicist Evelyn Byrd Harrison has observed. They are sometimes portrayed as the evening daughters of Night (Nyx) eit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rockall Trough
The Rockall Trough ( gd, Clais Sgeir Rocail) is a deep-water bathymetric feature to the northwest of Scotland and Ireland, running roughly from southwest to northeast, flanked on the north by the Rockall Plateau and to the south by the Porcupine Seabight. At the northern end, the channel is bounded by the Wyville-Thomson Ridge, named after Charles Wyville Thomson, professor of zoology at the University of Edinburgh and driving force behind the Challenger Expedition. At the southern end, the trough opens into the Porcupine abyssal plain. The Rockall Basin (also known as the Hatton Rockall Basin) is a large (c. 800 km by 150 km) sedimentary basin that lies beneath the trough. Both are named after Rockall, a rocky islet lying 301.4 km west of St Kilda. Features of the Rockall Plateau have been officially named after features of Middle-earth in the fiction of J. R. R. Tolkien, e.g. Eriador Seamount, Rohan Seamount, Gondor Seamount, Fangorn Bank, Edoras Bank, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
