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Musicians Seamounts
Musicians Seamounts are a chain of seamounts in the Pacific Ocean, north of the Hawaiian Ridge. There are about 65 seamounts, some of which are named after musicians. These seamounts exist in two chains, one of which has been attributed to a probably now-extinct hotspot called the Euterpe hotspot. Others may have formed in response to plate tectonics associated with the boundary between the Pacific Plate and the former Farallon Plate. The seamounts were constructed on young oceanic crust during the Cretaceous, but a second phase of volcanic activity took place during the Eocene. Deep sea coral reefs occur on the seamounts. Geography and geomorphology The Musicians Seamounts lie in the north-central Pacific, north of the Hawaiian Ridge north and northwest of Necker Island, extending over a length of . The seamounts were formerly known as the North Hawaiian Seamount Range and were among the first submarine mountains to be thoroughly researched. The seamounts consist of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaiian Seamount Chain
Hawaiian may refer to: * Native Hawaiians, the current term for the indigenous people of the Hawaiian Islands or their descendants * Hawaii state residents, regardless of ancestry (only used outside of Hawaii) * Hawaiian language Historic uses * things and people of the Kingdom of Hawaii, during the period from 1795 to 1893 * things and people of the Republic of Hawaii, the short period between the overthrow of the monarchy and U.S. annexation * things and people of the Territory of Hawaii, during the period the area was a U.S. territory from 1898 to 1959 * things and people of the Sandwich Islands, the name used for the Hawaiian Islands around the end of the 18th century Other uses * Hawaiian Airlines, a commercial airline based in Hawaii * Hawaiian pizza, a style of pizza topped with pineapple See also * Hawaiians (other) * Hawaiian cuisine (other) * Hawaiian Islands * Hawaiian kinship Hawaiian kinship, also referred to as the generational system, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remotely Operated Vehicle
A remotely operated underwater vehicle (technically ROUV or just ROV) is a tethered underwater mobile device, commonly called ''underwater robot''. Definition This meaning is different from remote control vehicles operating on land or in the air. ROVs are unoccupied, usually highly maneuverable, and operated by a crew either aboard a vessel/floating platform or on proximate land. They are common in deepwater industries such as offshore hydrocarbon extraction. They are linked to a host ship by a neutrally buoyant tether or, often when working in rough conditions or in deeper water, a load-carrying umbilical cable is used along with a tether management system (TMS). The TMS is either a garage-like device which contains the ROV during lowering through the splash zone or, on larger work-class ROVs, a separate assembly which sits on top of the ROV. The purpose of the TMS is to lengthen and shorten the tether so the effect of cable drag where there are underwater currents is minimize ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegirine
Aegirine is a member of the clino pyroxene group of inosilicate minerals. Aegirine is the sodium endmember of the aegirine- augite series. Aegirine has the chemical formula Na Fe Si2 O6 in which the iron is present as Fe3+. In the aegirine-augite series the sodium is variably replaced by calcium with iron(II) and magnesium replacing the iron(III) to balance the charge. Aluminium also substitutes for the iron(III). Acmite is a fibrous, green-colored variety. Aegirine occurs as dark green monoclinic prismatic crystals. It has a glassy luster and perfect cleavage. Its Mohs hardness varies from 5 to 6, and its specific gravity is between 3.2 and 3.4. This mineral commonly occurs in alkalic igneous rocks, nepheline syenites, carbonatites and pegmatites. It also appears in regionally metamorphosed schists, gneisses, and iron formations; in blueschist facies rocks, and from sodium metasomatism in granulites. It may occur as an authigenic mineral in shales and marls. It occurs in ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trachyte
Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava enriched with silica and alkali metals. It is the volcanic equivalent of syenite. Trachyte is common wherever alkali magma is erupted, including in late stages of ocean island volcanismMacDonald 1983, pp. 51-52 and in continental rift valleys, above mantle plumes,Philpotts and Ague 2009, pp. 390-394 and in areas of back-arc extension. Trachyte has also been found in Gale crater on Mars. Trachyte has been used as decorative building stone and was extensively used as dimension stone in the Roman Empire and the Republic of Venice. Chemical composition Trachyte has a silica content of 60 to 65% and an alkali oxide content of over 7%. This gives it less SiO2 than rhyolite and more (Na2O plus K2O) than dacite. These chemical differences are consistent with the positio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mugearite
Mugearite () is a type of oligoclase-bearing basalt, comprising olivine, apatite, and opaque oxides. The main feldspar in mugearite is oligoclase. Mugearite is a sodium-rich member of the alkaline magma series. In the TAS classification of volcanic rock, mugearite is classified as sodium-rich basaltic trachyandesite. Examples Western Scotland Mugearite was first identified at Mugeary on the island of Skye, Scotland by Alfred Harker in 1904. Outcrops of mugearite also occur on the island of Isle of Mull, Mull. These examples of mugearite were formed during a period of continental flood basalt volcanic activity that happened in western Scotland during the Paleogene Period (geology), period of the Earth's geological history, when the North Atlantic Ocean opened between Europe and North America. Oceanic islands Mugearite has been erupted by the volcanoes of some High island, oceanic islands at Hotspot (geology), hotspots. Examples are Hawaii (island), Hawaii, Ascension Island, Sai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaiite
Hawaiite is an olivine basalt with a composition between alkali basalt and mugearite. It was first used as a name for some lavas found on the island of Hawaii. It occurs during the later stages of volcanic activity on oceanic islands such as Hawaii, which happens to be when the alkaline metals are most present. In gemology, hawaiite is a colloquial term for Hawaii-originated peridot, which is a gem-quality form of the mineral olivine. Description Hawaiite is an aphanitic (fine-grained) volcanic rock produced by rapid cooling of lava moderately poor in silica and enriched in alkali metal oxides (potassium oxide plus sodium oxide). It is often impractical to determine the mineral composition of such a fine-grained rock, and so hawaiite is defined chemically. Under the TAS classification, hawaiite is sodic trachybasalt, with a silica content close to 49 wt%, a total alkali metal oxide content close to 6%, and wt% > wt% + 2. This places hawaiite in the S1 field of the TAS dia ... [...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] |
Equator
The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can also be used for any other celestial body that is roughly spherical. In spatial (3D) geometry, as applied in astronomy, the equator of a rotating spheroid (such as a planet) is the parallel (circle of latitude) at which latitude is defined to be 0°. It is an imaginary line on the spheroid, equidistant from its poles, dividing it into northern and southern hemispheres. In other words, it is the intersection of the spheroid with the plane perpendicular to its axis of rotation and midway between its geographical poles. On and near the equator (on Earth), noontime sunlight appears almost directly overhead (no more than about 23° from the zenith) every day, year-round. Consequently, the equator has a rather stable daytime temperature throug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleomagnetic
Paleomagnetism (or palaeomagnetismsee ), is the study of magnetic fields recorded in rocks, sediment, or archeological materials. Geophysicists who specialize in paleomagnetism are called ''paleomagnetists.'' Certain magnetic minerals in rock (geology), rocks can record the direction and intensity of Earth's magnetic field at the time they formed. This record provides information on the past behavior of the geomagnetic field and the past location of tectonic plates. The record of geomagnetic reversals preserved in Volcanic rock, volcanic and sedimentary rock sequences (magnetostratigraphy) provides a time-scale that is used as a geochronology, geochronologic tool. Evidence from paleomagnetism led to the revival of the continental drift hypothesis and its transformation into the modern theory of plate tectonics. Apparent polar wander paths provided the first clear geophysical evidence for continental drift, while marine magnetic anomaly, magnetic anomalies did the same for seafl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pioneer Fracture Zone
Pioneer commonly refers to a settler who migrates to previously uninhabited or sparsely inhabited land. In the United States pioneer commonly refers to an American pioneer, a person in American history who migrated west to join in settling and developing new areas. Pioneer, The Pioneer, or pioneering may also refer to: Companies and organizations * Pioneer Aerospace Corporation *Pioneer Chicken, an American fast-food restaurant chain *Pioneer Club Las Vegas, a casino in Las Vegas, Nevada, U.S. * Pioneer Corporation, a Japanese electronics manufacturer *Pioneer Energy, a Canadian gas station chain * Pioneer Entertainment, a Japanese anime company *Pioneer Hi-Bred, a U.S.-based agriculture company *Pioneer Hotel & Gambling Hall, Laughlin, Nevada, U.S. * Pioneer Instrument Company, an American aeronautical instrument manufacturer *Pioneer movement, a communist youth organization *Pioneer Natural Resources, an energy company in Texas, U.S. * Pioneer Pictures, a former American film s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murray Fracture Zone
Murray may refer to: Businesses * Murray (bicycle company), an American manufacturer of low-cost bicycles * Murrays, an Australian bus company * Murray International Trust, a Scottish investment trust * D. & W. Murray Limited, an Australian wholesale drapery business * John Murray (publishing house), a British publishing house Fictional characters *Murray Monster, a muppet in ''Sesame Street'' *Little Murray Sparkles, a cat in ''Sesame Street'' * Murray (''Monkey Island''), a character in the video game series * Murray (''Sly Cooper''), a character in the video game series *Murray Slaughter, a regular character in ''The Mary Tyler Moore Show'' *Murray, the mascot of the band Dio *Murray, in the 2015 Netflix series '' Richie Rich'' *Murray, a ''Hotel Transylvania'' character *Murray the Cop, in ''Fat Pizza'' *Murray Smith, in ''Swift and Shift Couriers'' People *Murray (surname) *Murray (given name) Places Australia * Division of Murray, federal electoral district in Victor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry William Menard
Henry William Menard (December 10, 1920 – February 9, 1986) was an American geologist. Life and career He earned a B.S. and M.S. from the California Institute of Technology in 1942 and 1947, having served in the South Pacific during World War II as a photo interpreter. In 1949, he completed a Ph.D. in marine geology at Harvard University. Menard is perhaps best known for his promotion of the theory of plate tectonics before it was widely accepted in the scientific community. Menard served many roles during his career as a marine geologist. Field worker, theorist, educator, popularizer, entrepreneur and statesman. Menard's historical and sociological writings are respected by historians of science. Menard began his professional career in 1949, in the Sea Floor Studies Section of San Diego's Navy Electronics Laboratory. He joined the Scripps Institution of Oceanography (SIO) in 1955 as associate professor of geology. Menard's field work was extensive, involving 1,000 aqua-lung d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
