|
Saya De Malha
The Saya de Malha Bank (also the Sahia de Malha Bank, modern Portuguese: ''saia de malha'', English: ''mesh skirt'') or Mesh Skirt Bank, is one of the largest submerged ocean banks in the world, a part of the vast undersea Mascarene Plateau. Geography The Saya de Malha Bank lies northeast of Madagascar, southeast of Seychelles, and north of Nazareth Bank, the Cargados Carajos Shoals, and the island of Mauritius, and currently falls mostly under international waters. The closest land is tiny Agaléga (one of the Outer Islands of Mauritius), some further west, followed by the southern Seychellois island of Coëtivy, some northwest. Mauritius administers the whole Saya de Malha Bank as a portion of it lies within its exclusive economic zone. The bank covers an area of , and is composed of two separate structures, the smaller North Bank (also called Ritchie Bank), and the huge South Bank. If the South Bank were recognized as a submerged atoll structure, it would be the largest o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean Bank
An ocean bank, sometimes referred to as a fishing bank or simply bank, is a part of the seabed that is shallow compared to its surrounding area, such as a shoal or the top of an underwater hill. Somewhat like continental slopes, ocean bank slopes can upwell as tidal and other flows intercept them, sometimes resulting in nutrient-rich currents. Because of this, some large banks, such as Dogger Bank and the Grand Banks of Newfoundland, are among the richest fishing grounds in the world. There are some banks that were reported in the 19th century by navigators, such as Wachusett Reef, whose existence is doubtful. Types Ocean banks may be of volcanic nature. Banks may be carbonate or terrigenous. In tropical areas some banks are submerged atolls. As they are not associated with any landmass, banks have no outside source of sediments. Carbonate banks are typically platforms, rising from the ocean depths, whereas terrigenous banks are elevated sedimentary deposits. Sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Fault
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A '' fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Equatorial Current
The South Equatorial Current are ocean currents in the Pacific, Atlantic, and Indian Ocean that flow east-to-west between the equator and about 20 degrees south. In the Pacific and Atlantic Oceans, it extends across the equator to about 5 degrees north. Within the southern hemisphere, the South Equatorial Current is the westward limb of the very large-scale subtropical gyres. These gyres are driven by the combination of trade winds in the tropics and westerly winds that are found south of about 30 degrees south, through a rather complicated process that includes western boundary current intensification. On the equator, the South Equatorial Current is driven directly by the trade winds which blow from east to west. In the Indian Ocean, the westward-flowing South Equatorial Current is well-developed only south of the equator. Directly on the equator, the winds reverse twice a year due to the monsoons, and so the surface current can be either eastward or westward. Sources ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neogene
The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of the Cenozoic and the eleventh period of the Phanerozoic. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene. Some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes (1815–1868). The earlier term Tertiary Period was used to define the span of time now covered by Paleogene and Neogene and, despite no longer being recognized as a formal stratigraphic term, "Tertiary" still sometimes remains in informal use. During this period, mammals and birds continued to evolve into modern forms, while other groups of life remained relatively unchanged. The first human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Réunion
Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas departments and regions of France, overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the island of Madagascar and southwest of the island of Mauritius. , it had a population of 896,175. Its capital and largest city is Saint-Denis, La Réunion, Saint-Denis. Réunion was uninhabited until French immigrants and colonial subjects settled the island in the 17th century. Its tropical climate led to the development of a plantation economy focused primarily on sugar; slaves from East Africa were imported as fieldworkers, followed by Malays, Annamite, Vietnamese, Chinese, and Indians as indentured laborers. Today, the greatest proportion of the population is of mixed descent, while the predominant language is Réunion Creole, though French remains the sole official language. Since 1946, Réunion has been governed as a regions of France, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of calcium carbonate . Limestone forms when these minerals Precipitation (chemistry), precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly Dolomite (rock), dolomite, a closely related rock, which contains a high percentage of the mineral Dolomite (mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Réunion Hotspot
The Réunion hotspot is a volcanic hotspot which currently lies under the island of Réunion in the Indian Ocean. The Chagos-Laccadive Ridge and the southern part of the Mascarene Plateau are volcanic traces of the Réunion hotspot. The hotspot is believed to have been active for over 65 million years. A huge eruption of this hotspot 65 million years ago is thought to have laid down the Deccan Traps, a vast bed of basalt lava that covers part of central India, and opened a rift which separated India from the Seychelles Plateau. The Deccan Traps eruption coincided roughly with the nearly antipodal Chicxulub impactor and the Cretaceous–Paleogene extinction of the dinosaurs, and there is considerable speculation that the three events were related. As the Indian plate drifted north, the hotspot continued to punch through the plate, creating a string of volcanic islands and undersea plateaux. The Laccadive Islands, the Maldives, and the Chagos Archipelago are atolls resting o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Whale
The blue whale (''Balaenoptera musculus'') is a marine mammal and a baleen whale. Reaching a maximum confirmed length of and weighing up to , it is the largest animal known ever to have existed. The blue whale's long and slender body can be of various shades of greyish-blue on its upper surface and somewhat lighter underneath. Four subspecies are recognized: ''B. m. musculus'' in the North Atlantic and North Pacific, ''B. m. intermedia'' in the Southern Ocean, ''B. m. brevicauda'' (the pygmy blue whale) in the Indian Ocean and South Pacific Ocean, and ''B. m. indica'' in the Northern Indian Ocean. There is a population in the waters off Chile that may constitute a fifth subspecies. In general, blue whale populations migrate between their summer feeding areas near the poles and their winter breeding grounds near the tropics. There is also evidence of year-round residencies, and partial or age/sex-based migration. Blue whales are filter feeders; their diet consists almost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humpback Whale
The humpback whale (''Megaptera novaeangliae'') is a species of baleen whale. It is a rorqual (a member of the family Balaenopteridae) and is the monotypic taxon, only species in the genus ''Megaptera''. Adults range in length from and weigh up to . The humpback has a distinctive body shape, with long pectoral fins and tubercles on its head. It is known for Cetacean surfacing behaviour, breaching and other distinctive surface behaviors, making it popular with whale watching, whale watchers. Males produce a complex Whale sound, song that typically lasts from 4 to 33 minutes. Found in oceans and list of seas, seas around the world, humpback whales typically animal migration, migrate between feeding areas towards the poles and breeding areas near the equator. They feed in Polar region, polar waters and migrate to tropics, tropical or subtropical waters to breed and give birth. Their diet consists mostly of krill and small fish, and they usually Bubble-net feeding, use bubbles to c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Ecoregion
A marine ecoregion is an ecoregion, or ecological region, of the oceans and seas identified and defined based on biogeographic characteristics. Introduction A more complete definition describes them as “Areas of relatively homogeneous species composition, clearly distinct from adjacent systems” dominated by “a small number of ecosystems and/or a distinct suite of oceanographic or topographic features”. Ecologically they “are strongly cohesive units, sufficiently large to encompass ecological or life history processes for most sedentary species.”Spalding, Mark D., Helen E. Fox, Gerald R. Allen, Nick Davidson et al. "Marine Ecoregions of the World: A Bioregionalization of Coastal and Shelf Areas". Bioscience Vol. 57 No. 7, July/August 2007, pp. 573–58/ref> Marine Ecoregions of the World—MEOW The global classification system Marine Ecoregions of the World—MEOW was devised by an international team, including major conservation organizations, academic institutions an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral Reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and jellyfish. Unlike sea anemones, corals secrete hard carbonate exoskeletons that support and protect the coral. Most reefs grow best in warm, shallow, clear, sunny and agitated water. Coral reefs first appeared 485 million years ago, at the dawn of the Early Ordovician, displacing the microbial and sponge reefs of the Cambrian. Sometimes called ''rainforests of the sea'', shallow coral reefs form some of Earth's most diverse ecosystems. They occupy less than 0.1% of the world's ocean area, about half the area of France, yet they provide a home for at least 25% of all marine species, including fish, mollusks, worms, crustaceans, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
