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Daikoku Seamount
Daikoku Seamount () is a submarine volcano located in the Northern Mariana Islands, in the western Pacific Ocean. It is situated on the Izu–Bonin–Mariana arc, Mariana volcanic arc. The seamount rises over meters from the seafloor, with its summit about below sea level. Since its discovery, the seamount has been studied by several expeditions, including expeditions made by NOAA, using various scientific tools, such as Sonar#Bathymetric mapping, sonar mapping and Remotely operated underwater vehicle, remotely operated vehicles (ROVs). Daikoku Seamount hosts an active hydrothermal vent system that hosts diverse communities of deep-sea organisms, including tube worms, crabs, and snails. At the summit of the seamount, a crater filled with molten liquid sulfur called "Sulfur Cauldron" exists, which was discovered in 2006. In 2014, it was discovered in an expedition that the seamount had erupted, forming 2 new craters on the summit. Geography The seamount is located around north ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Mariana Islands
The Northern Mariana Islands, officially the Commonwealth of the Northern Mariana Islands (CNMI), is an Territories of the United States, unincorporated territory and Commonwealth (U.S. insular area), commonwealth of the United States consisting of 14 islands in the northwestern Pacific Ocean.Lin, Tom C.W.Americans, Almost and Forgotten 107 California Law Review (2019) The CNMI includes the 14 northernmost islands in the Mariana Islands, Mariana Archipelago; the southernmost island, Guam, is a separate U.S. territory. The Northern Mariana Islands were listed by the United Nations as a non-self-governing territory until 1990. During the colonial period, the Northern Marianas were variously under the control of the Spanish Empire, Spanish, German colonial empire, German, and Empire of Japan, Japanese empires. After World War II, the islands were part of the United Nations trust territories under American administration before formally joining the United States as a territory in 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanism On Io
Io (moon), Io, a Moons of Jupiter, moon of Jupiter, has a substantial presence of volcanoes, patera (planetary nomenclature), volcanic pits and lava flows on its surface. Volcanic activity on the moon was first discovered in 1979 by Linda Morabito, an imaging science, imaging scientist working on ''Voyager 1''. Observations of Io by passing spacecraft and Earth-based astronomers have revealed more than 150 active volcanoes. , up to 400 such volcanoes are predicted to exist based on these observations. Io's volcanism makes the satellite one of only five known currently volcanically or Cryovolcano, cryovolcanically active worlds in the Solar System (the others being Earth, Venus, Saturn's moon Enceladus, and Neptune's moon Triton (moon), Triton.) First predicted shortly before the ''Voyager 1'' flyby, the heat source for Io's volcanism comes from tidal heating produced by its forced orbital eccentricity. This differs from Geothermal gradient, Earth's internal heating, which is deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Rocks
Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and metamorphic rocks and constitute an important element of some sediments and sedimentary rocks. For these reasons, in geology, volcanics and shallow hypabyssal rocks are not always treated as distinct. In the context of Precambrian shield geology, the term "volcanic" is often applied to what are strictly metavolcanic rocks. Volcanic rocks and sediment that form from magma erupted into the air are called "pyroclastics," and these are also technically sedimentary rocks. Volcanic rocks are among the most common rock types on Earth's surface, particularly in the oceans. On land, they are very common at plate boundaries and in flood basalt provinces. It has been estimated that volcanic rocks cover about 8% of the Earth's current land surface. Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pumice
Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of extremely vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular volcanic rock that differs from pumice in having larger vesicles, thicker vesicle walls, and being dark colored and denser.Jackson, J.A., J. Mehl, and K. Neuendorf (2005) ''Glossary of Geology'' American Geological Institute, Alexandria, Virginia. 800 pp. McPhie, J., M. Doyle, and R. Allen (1993) ''Volcanic Textures A guide to the interpretation of textures in volcanic rocks'' Centre for Ore Deposit and Exploration Studies, University of Tasmania, Hobart, Tasmania..198 pp. Pumice is created when super-heated, highly pressurized rock is rapidly ejected from a volcano. The unusual foamy configuration of pumice happens because of simultaneous rapid cooling and rapid depressurization. The depressurization creates bubbles by lowering the sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Ash
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, produced during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as '' tephra''), including particles larger than 2 mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the gases shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometres away. Due to its wide dispersal, ash can have a number of impacts on society, including animal a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratovolcanoes
A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and explosive eruptions. Some have collapsed summit craters called calderas. The lava flowing from stratovolcanoes typically cools and solidifies before spreading far, due to high viscosity. The magma forming this lava is often felsic, having high to intermediate levels of silica (as in rhyolite, dacite, or andesite), with lesser amounts of less viscous mafic magma. Extensive felsic lava flows are uncommon, but can travel as far as 8 km (5 mi). The term ''composite volcano'' is used because strata are usually mixed and uneven instead of neat layers. They are among the most common types of volcanoes; more than 700 stratovolcanoes have erupted lava during the Holocene Epoch (the last 11,700 years), and many older, now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariana Trench
The Mariana Trench is an oceanic trench located in the western Pacific Ocean, about east of the Mariana Islands; it is the deep sea, deepest oceanic trench on Earth. It is crescent-shaped and measures about in length and in width. The maximum known depth is at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. The deepest point of the trench is more than farther from sea level than the peak of Mount Everest. At the bottom of the trench, the water column above exerts a pressure of , more than 1,071 times the standard atmospheric pressure at sea level. At this pressure, the density of water is increased by 4.96%. The temperature at the bottom is . In 2009, the Mariana Trench was established as a National monument (United States), US National Monument, Mariana Trench Marine National Monument. One-celled organisms called monothalamea have been found in the trench at a record depth of below the sea surface by researchers from the Scrip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariana Plate
The Mariana plate is a micro tectonic plate located west of the Mariana Trench which forms the basement of the Mariana Islands which form part of the Izu–Bonin–Mariana Arc. It is separated from the Philippine Sea plate to the west by a divergent boundary with numerous transform fault offsets. The boundary between the Mariana and the Pacific plate to the east is a subduction zone with the Pacific plate subducting beneath the Mariana. This eastern subduction is divided into the Mariana Trench, which forms the southeastern boundary, and the Izu–Ogasawara Trench the northeastern boundary. The subduction plate motion is responsible for the shape of the Mariana plate and back arc. Geological history Subduction at the Mariana plate has been going on for over 50 million years. Some theories of the origin of this microplate is that when the Pacific plate began to subduct beneath the Philippine plate the volcanism and spreading ridge started to make an arc. This geological activ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonic Plate
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called ''tectonics''. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annually. Faults tend to be geologically active, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other 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 rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariana Subduction
Mariana is a given name (the link includes a list of people of this name). Mariana may also refer to: Literature * ''Mariana'' (Dickens novel), a 1940 novel by Monica Dickens * ''Mariana'' (poem), a poem by Alfred Tennyson, 1st Baron Tennyson * ''Mariana'' (Vaz novel), a 1997 novel by Katherine Vaz Music *"Mariana", a song by Alberto Cortez *"Mariana", a song by Collectif Métissé *"Mariana", a song by Gibson Brothers Places *Mariana, Minas Gerais, Brazil **Roman Catholic Archdiocese of Mariana * Mariana Lake, Alberta, Canada *Mariana, Corsica ** Roman Catholic Diocese of Mariana in Corsica * Mariana, Humacao, Puerto Rico, a barrio * Mariana, Naguabo, Puerto Rico, a barrio * Mariana, Cuenca, a municipality in the province of Cuenca, Spain *Mariana, a Roman town in Hispania, currently named Puebla del Príncipe, in Ciudad Real, Spain *Mariana, village in Banyuasin Regency, South Sumatra, Indonesia *Mariana, village in Pontianak, West Kalimantan, Indonesia *Mariana, Quezon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
