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Lava Bed
Lava fields are large, mostly flat areas of surface or subaquatic lava flows. Such features are generally composed of highly fluid basalt lava, and can extend for tens or hundreds of miles across the underlying terrain. Morphology and structure The final morphology of a lava field can reveal properties such as internal structure, composition, and mechanics of the lava flow when it was fluid. The ridges and patterns on top of the lava field show the direction of the channels and the oftentimes active lava tubes that may be underneath the solidified "crust." It can also reveal whether the lava flow can be classified as pāhoehoe or 'a'ā. The two main types of lava field structures are defined as sheet flow lava and pillow lava. Sheet flow lava appears like a wrinkled or folded sheet, while pillow lava is bulbous, and often looks like a pile of pillows atop one another. An important aspect of lava flow morphology is a phenomenon known as lava flow inflation. This occurs in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hell's Half Acre Lava Field
Hell's Half Acre Lava Field is a basaltic lava plain located on the Snake River Plain of Idaho in the United States. It is the easternmost of the basaltic lava fields on the Snake River Plain, located about west of Idaho Falls, Idaho and north of Pocatello, Idaho. In 1976, the National Park Service designated the northwestern portion of the site a National Natural Landmark. In 1986, the Bureau of Land Management recommended that of the site, located just southeast of the National Natural Landmark, to be a wilderness study area. Description of the site The Hell's Half Acre lava plain is located in Bingham and Bonneville counties in the state of Idaho. The site is about in size. The area where a former lava lake existed is marked by a long by wide depression near the summit of the lava field.Link and Mink, ''Geology, Hydrogeology, and Environmental Remediation: Idaho National Engineering and Environmental Laboratory, Eastern Snake River Plain, Idaho,'' 2001, p. 117. Ten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Fields
Lava fields are large, mostly flat areas of surface or subaquatic lava flows. Such features are generally composed of highly fluid basalt lava, and can extend for tens or hundreds of miles across the underlying terrain. Morphology and structure The final morphology of a lava field can reveal properties such as internal structure, composition, and mechanics of the lava flow when it was fluid. The ridges and patterns on top of the lava field show the direction of the channels and the oftentimes active lava tubes that may be underneath the solidified "crust." It can also reveal whether the lava flow can be classified as pāhoehoe or 'a'ā. The two main types of lava field structures are defined as sheet flow lava and pillow lava. Sheet flow lava appears like a wrinkled or folded sheet, while pillow lava is bulbous, and often looks like a pile of pillows atop one another. An important aspect of lava flow morphology is a phenomenon known as lava flow inflation. This occurs in p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcano
A volcano is a rupture in the Crust (geology), crust of a Planet#Planetary-mass objects, planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and volcanic gas, gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where list of tectonic plates, tectonic plates are divergent boundary, diverging or convergent boundary, converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanism Of Iceland
:''The volcano system in Iceland that started activity on August 17, 2014, and ended on February 27, 2015, is Bárðarbunga.'' :''The volcano in Iceland that erupted in May 2011 is Grímsvötn.'' Iceland experiences frequent volcanic activity, due to its location both on the Mid-Atlantic Ridge, a divergent tectonic plate boundary, and over a hot spot. Nearly thirty volcanoes are known to have erupted in the Holocene epoch; these include Eldgjá, source of the largest lava eruption in human history. Volcanic systems and volcanic zones of Iceland Holocene volcanism in Iceland is mostly to be found in the ''Neovolcanic Zone'', comprising the Reykjanes Volcanic Belt (RVB), the West Volcanic Zone (WVZ), the Mid-Iceland Belt (MIB), the East Volcanic Zone (EVZ) and the North Volcanic Zone (NVZ). Two lateral volcanic zones play a minor role: Öræfi Volcanic Belt (ÖVB) and Snæfellsnes Volcanic Belt (SVB). Outside of the main island are the Reykjanes Ridge (RR), as part of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 most volcanoes are created by geological activity at tectonic plate boundaries, 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 then, cut off from their source by the movement of the Pacific Plate, become increasingly inactive and eventually erode below sea level over ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Plateau
A volcanic plateau is a plateau produced by volcanic activity. There are two main types: lava plateaus and pyroclastic plateaus. Lava plateau Lava plateaus are formed by highly fluid basaltic lava during numerous successive eruptions through numerous vents without violent explosions (quiet eruptions). These eruptions are quiet because of low viscosity of lava, so that it is very fluid and contains a small amount of trapped gases. The resulting sheet lava flows may be extruded from linear fissures or rifts or gigantic volcanic eruptions through multiple vents characteristic of the prehistoric era which produced giant flood basalts. Multiple successive and extensive lava flows cover the original landscape to eventually form a plateau, which may contain lava fields, cinder cones, shield volcanoes and other volcanic landforms. In some cases, a lava plateau may be part of a single volcano. An example is the massive Level Mountain shield volcano in northern British Columbia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Field
A volcanic field is an area of Earth's crust that is prone to localized volcanic activity. The type and number of volcanoes required to be called a "field" is not well-defined. Volcanic fields usually consist of clusters of up to 100 volcanoes such as cinder cones. Lava flows may also occur. They may occur as a monogenetic volcanic field or a polygenetic volcanic field. Description Alexander von Humboldt observed in 1823 that geologically young volcanoes are not distributed uniformly across the Earth's surface, but tend to be clustered into specific regions. Young volcanoes are rarely found within cratons, but are characteristic of subduction zones, rift zones, or in ocean basins. Intraplate volcanoes are clustered along hotspot traces. Within regions of volcanic activity, volcanic fields are clusters of volcanoes that share a common magma source. Scoria cones are particularly prone to cluster into volcanic fields, which are typically in diameter and consist of several t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by total area. Its southern and western border with the United States, stretching , is the world's longest binational land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mackenzie Large Igneous Province
The Mackenzie Large Igneous Province (MLIP) is a major Mesoproterozoic large igneous province of the southwestern, western and northwestern Canadian Shield in Canada. It consists of a group of related igneous rocks that were formed during a massive igneous event starting about 1,270 million years ago. The large igneous province extends from the Arctic in Nunavut to near the Great Lakes in Northwestern Ontario where it meets with the smaller Matachewan dike swarm. Included in the Mackenzie Large Igneous Province are the large Muskox layered intrusion, the Coppermine River flood basalt sequence and the massive northwesterly trending Mackenzie dike swarm. As a large igneous province, it is an extremely large area of related igneous rocks that were emplaced over an extremely short geological time span. The igneous rocks comprising the Mackenzie Large Igneous Province originated from processes not associated with normal plate tectonics and seafloor spreading. It is one of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its west by Nevada. Utah also touches a corner of New Mexico in the southeast. Of the fifty U.S. states, Utah is the 13th-largest by area; with a population over three million, it is the 30th-most-populous and 11th-least-densely populated. Urban development is mostly concentrated in two areas: the Wasatch Front in the north-central part of the state, which is home to roughly two-thirds of the population and includes the capital city, Salt Lake City; and Washington County in the southwest, with more than 180,000 residents. Most of the western half of Utah lies in the Great Basin. Utah has been inhabited for thousands of years by various indigenous groups such as the ancient Puebloans, Navajo and Ute. The Spanish were the first Europe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peninsula
A peninsula (; ) is a landform that extends from a mainland and is surrounded by water on most, but not all of its borders. A peninsula is also sometimes defined as a piece of land bordered by water on three of its sides. Peninsulas exist on all continents. The size of a peninsula can range from tiny to very large. The largest peninsula in the world is the Arabian Peninsula. Peninsulas form due to a variety of causes. Etymology Peninsula derives , which is translated as 'peninsula'. itself was derived , or together, 'almost an island'. The word entered English in the 16th century. Definitions A peninsula is usually defined as a piece of land surrounded on most, but not all sides, but is sometimes instead defined as a piece of land bordered by water on three of its sides. A peninsula may be bordered by more than one body of water, and the body of water does not have to be an ocean or a sea. A piece of land on a very tight river bend or one between two rivers is sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
%2C_Reykjanes_peninsula.JPG "Click for more on -> Lava Fields")
