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Louisville Ridge
The Louisville Ridge, often now referred to as the Louisville Seamount Chain, is an underwater chain of over 70 seamounts located in the Southwest portion of the Pacific Ocean. One of the longest seamount chains on Earth, it stretches some Vanderkluysen, L.; Mahoney, J. J.; Koppers, A. A.; and Lonsdale, P. F. (2007)Geochemical Evolution of the Louisville Seamount Chain American Geophysical Union, Fall Meeting 2007, abstract #V42B-06. from the Pacific-Antarctic Ridge northwest to the Tonga-Kermadec Trench, where it subducts under the Indo-Australian Plate as part of the Pacific Plate. The chain's formation is best explained by movement of the Pacific Plate over the Louisville hotspot, although others have suggested that it formed by leakage of magma from the shallow mantle up through the Eltanin fracture zone, which it follows closely for some of its course. Depth-sounding data first revealed existence consistent with a seamount chain in 1972, although some of the seamounts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Louisville Seamount Chain - Bathymetry
Louisville is the List of cities in Kentucky, most populous city in the Commonwealth of Kentucky, sixth-most populous city in the Southeastern United States, Southeast, and the list of United States cities by population, 27th-most-populous city in the United States. By land area, it is the country's List of United States cities by area, 24th-largest city; however, by population density, it is the 265th most dense city. Louisville is the historical county seat and, since 2003, the nominal seat of Jefferson County, Kentucky, Jefferson County, on the Indiana border. Since 2003, Louisville and Jefferson County have shared the same borders following a consolidated city-county, city-county merger. The consolidated government is officially called the Louisville/Jefferson County Metro Government, commonly known as Louisville Metro. The term "Jefferson County" is still used in some contexts, especially for Louisville neighborhoods#Incorporated places, incorporated cities outside the "Lou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Osbourn Seamount
The Osbourn Seamount is a seamount in the south-west Pacific Ocean. It is the westernmost and oldest unsubducted seamount of the Louisville Ridge, with an estimated age of 78.8 ± 1.3 . Like other seamounts comprising the Louisville Ridge, it was formed by the Louisville hotspot which is currently located away near the Pacific-Antarctic Ridge. Osbourn Seamount will eventually be destroyed by subduction in the Tonga and Kermadec trenches once it is carried into the trenches by the ongoing plate motion. The trench-chain collision zone is moving southward at a rate of / because of the oblique angle between the trench and the Louisville chain. This further shortens the seamount's lifespan. The flat top of the seamount is currently tilting down toward the trench because the seamount is sitting on the edge of the trench where the Australian Plate is being bent by subduction. A bathymetric high north-west of the Osbourn Seamount has been interpreted as the currently subdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hoplostethus Atlanticus
The orange roughy (''Hoplostethus atlanticus''), also known as the red roughy, slimehead and deep sea perch, is a relatively large deep-sea fish belonging to the slimehead Family (biology), family (Trachichthyidae). It is bathypelagic, found in cold (), deep () waters of the Western Pacific Ocean, eastern Atlantic Ocean (from Iceland to Morocco; and from Walvis Bay, Namibia, to off Durban, South Africa), Indo-Pacific (off New Zealand and Australia), and in the eastern Pacific off Chile. The orange roughy is notable for its extraordinary lifespan, attaining over 200 years. The fish has a bright, brick red color, fading to a yellowish-orange after death. Like other slimeheads, orange roughy is slow-growing and late to mature, resulting in a very low Fish stocks, stock resilience, making them extremely susceptible to overfishing. Despite this, the species is important to commercial deep-trawl fisheries; many stocks (especially those off New Zealand and Australia, which were first exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Crinoidea
Crinoids are marine invertebrates that make up the class Crinoidea. Crinoids that remain attached to the sea floor by a stalk in their adult form are commonly called sea lilies, while the unstalked forms, called feather stars or comatulids, are members of the largest crinoid order, Comatulida. Crinoids are echinoderms in the phylum Echinodermata, which also includes the starfish, brittle stars, sea urchins and sea cucumbers. They live in both shallow water and in depths of over . Adult crinoids are characterised by having the mouth located on the upper surface. This is surrounded by feeding arms, and is linked to a U-shaped gut, with the anus being located on the oral disc near the mouth. Although the basic echinoderm pattern of fivefold symmetry can be recognised, in most crinoids the five arms are subdivided into ten or more. These have feathery pinnules and are spread wide to gather planktonic particles from the water. At some stage in their lives, most crinoids have a short ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Brisingida
The Brisingids are deep-sea-dwelling starfish in the order Brisingida. Description These starfish have between 6 and 16 long, attenuated arms which they use for suspension feeding. Other characteristics include a single series of marginals, a fused ring of disc plates, the lack of actinal plates, a spool-like ambulacral column, reduced abactinal plates, and crossed pedicellariae. They are 40 times the size of disk radius and have 7–20 flexible spiny arms. Distribution Brisingida occur in a number of deep-sea locations, particularly in the Caribbean and New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla .... This type of species are found of varying size especially in the eastern Pacific Ocean at a depth of 1,820–2,418 m. Taxonomy The Brisingida contain two fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Starfish
Starfish or sea stars are Star polygon, star-shaped echinoderms belonging to the class (biology), class Asteroidea (). Common usage frequently finds these names being also applied to brittle star, ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish live on the seabed in all the world's oceans, from warm, tropics, tropical zones to frigid, polar regions of Earth, polar regions. They are found from the intertidal zone down to abyssal zone, abyssal depths, at below the surface. Starfish are marine invertebrates. They typically have a central disc and usually five arms, though some species have a larger number of arms. The aboral or upper surface may be smooth, granular or spiny, and is covered with overlapping plates. Many species are brightly coloured in various shades of red or orange, while others are blue, grey or brown. Starfish have tube fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Solenosmilia Variabilis
''Solenosmilia variabilis'' is a species of colonial coral in the family Caryophylliidae. It is a deep water, azooxanthellate coral with a semi-cosmopolitan distribution. Description ''Solenosmilia variabilis'' grows into small bushy colonies, the dichotomous branches often joining. It grows from an encrusting base on which there are a few corallites. The branches are thick near the base of the colony but more slender above; sometimes upper branches are just in diameter. The coenosteum can be smooth and white, granular, glossy and pale grey, or ridged with eight to ten transverse costae. The corallites are up to in diameter, with the septa grouped in sixes, arranged in three or more cycles. Growth of the colony is by intratentacular budding. Distribution ''S. variabilis'' has a semi-cosmopolitan distribution. It is widespread in both the Atlantic and Indian Oceans and has a circumpolar distribution in the Southern Ocean. Locations where it has been found include off South ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Seismic Gap
A seismic gap is a segment of an active fault known to produce significant earthquakes that has not slipped in an unusually long time, compared with other segments along the same structure. There is a hypothesis or theory that states that over long periods, the displacement on any segment must be equal to that experienced by all the other parts of the fault. Any large and longstanding gap is, therefore, considered to be the fault segment most likely to suffer future earthquakes. The applicability of this approach has been criticised by some seismologists, although earthquakes sometimes have occurred in previously identified seismic gaps. Examples Loma Prieta Seismic Gap, California Prior to the 1989 Loma Prieta earthquake( = 6.9), that segment of the San Andreas Fault system recorded much less seismic activity than other parts of the fault. The main shock and aftershocks of the 1989 event occurred within the previous seismic gap. Central Kuril gap, Russia Immediately following th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Arago Hotspot
Arago hotspot (also known as the Rurutu hotspot, Young Rurutu hotspot or Atiu hotspot) is a hotspot in the Pacific Ocean, presently located below the Arago seamount close to the island of Rurutu, French Polynesia. Arago is part of a family of hotspots in the southern Pacific, which include the Society hotspot and the Macdonald hotspot among others. These are structures beneath Earth's crust which generate volcanoes and which are in part formed by mantle plumes, although Arago itself might have a shallower origin. As the Pacific plate moves over the hotspots, new volcanoes form and old volcanoes are carried away; sometimes an older volcano is carried over the hotspot and is then uplifted as happened with Rurutu. The Arago hotspot is responsible for the formation of Arago seamount and uplift on Rurutu; however reconstructions of the past positions of tectonic plates and geochemistry suggest that other islands and seamounts were constructed by the Arago hotspot during the past ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Hawaii Hotspot
The Hawaii hotspot is a volcanic hotspot located near the namesake Hawaiian Islands, in the northern Pacific Ocean. One of the best known and intensively studied hotspots in the world, the Hawaii plume is responsible for the creation of the Hawaiian–Emperor seamount chain, a mostly undersea volcanic mountain range. Four of these volcanoes are active, two are dormant; more than 123 are extinct, most now preserved as atolls or seamounts. The chain extends from south of the island of Hawaii to the edge of the Aleutian Trench, near the eastern coast of Russia. While some volcanoes are created by geologic processes near tectonic plate convergence and subduction zones, the Hawaii hotspot is located far from plate boundaries. The classic hotspot theory, first proposed in 1963 by John Tuzo Wilson, proposes that a single, fixed mantle plume builds volcanoes that are then cut off from their source by the movement of the Pacific plate. This causes less lava to erupt from these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tectonics
Tectonics ( via Latin ) are the processes that result in the structure and properties of the Earth's crust and its evolution through time. The field of ''planetary tectonics'' extends the concept to other planets and moons. These processes include those of orogeny, mountain-building, the growth and behavior of the strong, old cores of continents known as cratons, and the ways in which the relatively rigid tectonic plate, plates that constitute the Earth's outer shell interact with each other. Principles of tectonics also provide a framework for understanding the earthquake and volcanic belts that directly affect much of the global population. Tectonic studies are important as guides for economic geology, economic geologists searching for fossil fuels and ore deposits of metallic and nonmetallic resources. An understanding of tectonic principles can help geomorphology, geomorphologists to explain Erosion and tectonics, erosion patterns and other Earth-surface features. Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Volcanic Hotspot
In geology, hotspots (or hot spots) are volcanic locales thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Examples include the Hawaii, Iceland, and Yellowstone hotspots. A hotspot's position on the Earth's surface is independent of tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. The alternative plate theory is that the mantle source beneath a hotspot is not anomalously hot, rather the crust above is unusually weak or thin, so that lithospheric extension permits the passive rising of melt from shallow depths. Origin The origins of the concept of hotspots lie in the work of J. Tuzo Wilson, who postulated in 1963 that the formation of the Hawaiian Islands resulted from the slow movement of a tect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
