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Železná Hůrka
Železná hůrka () is an extinct Quaternary volcano and a Protected areas of the Czech Republic, national nature monument in the Fichtel Mountains in the Czech Republic. Location Železná hůrka is located about 1 km south of Mýtina in the Lipová (Cheb District), Lipová municipality, in Cheb District in the Karlovy Vary Region of the Czech Republic. It lies in the easternmost part of the Fichtel Mountains. The area has also other manifestations of volcanic activity. Another Quaternary volcano, Komorní hůrka, is located nearby. CO2 outgassing occurs in the area. Metallic iron The name means "iron hill" in Czech. Fragments of metallic iron are found in the local basalt deposits. Iron usually occurs on Earth only in the oxidized form, as iron ore, and needs to be processed into metallic iron by smelting. It is thought that in the Železná hůrka area, iron-rich magma entered coal deposits which caused iron compounds to be reduced to metallic iron, in a process similar to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fichtel Mountains
The Fichtel Mountains (, ; ) is a mountain range in Germany and the Czech Republic. They extend from the valley of the Red Main River in northeastern Bavaria to the Karlovy Vary Region in western Czech Republic. The Fichtel Mountains contain an important nature park, the Fichtel Mountain Nature Park. The Elster Mountains are a part of the Fichtel Mountains. Etymology The first person to write about the Fichtel Mountains, Matthias of Kemnath (actually Matthias Widmann, born 23 February 1429 in Kemnath) reported in 1476: ''Ein bergk, hoch, weitt, wolbekant ligt in Beiern, gnant der Fichtelberg'' ("A mountain, high, wide and well-known, lies in Bavaria, known as the Fichtelberg"). In descriptions of the border in 1499 and 1536, the mountain that is now called the Ochsenkopf (Fichtel Mountains), Ochsenkopf was called ''Vichtelberg''; thereafter the name was extended to the whole mountain region. It is also mentioned in old documents: around 1317 the lords of Hirschberg were enfeof ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Železná Hůrka červenec 2015 (3)
{{DEFAULTSORT:Zelezna ...
Železná may refer to: *Železná (Beroun District), a municipality and village in the Central Bohemian Region of the Czech Republic *Železná Breznica, a municipality and village of the Zvolen District in the Banská Bystrica Region of Slovakia *Železná Ruda, a town in the Plzeň Region of the Czech Republic See also *Bratislava Železná studienka railway station, Slovakia * Železný (male form) *Železnice *Železnik *Železniki *Železné *Železník (other) *Željeznica (other) Željeznica may refer to: * Željeznica (Bosna), a river in Bosnia and Herzegovina, tributary of Bosna River * Željeznica (Fojnička River), alternative name Gvožđanka, a river in Bosnia and Herzegovina, source tributary of Fojnička River * Že ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maar
A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow crater lake, which may also be called a maar.David S.G. Thomas and Andrew Goudie (eds.), ''The Dictionary of Physical Geography'' (Oxford: Blackwell, 2000), 301. . Maars range in size from across and from deep. Most maars fill with water to form natural lakes. Most maars have low rims composed of a mixture of loose fragments of volcanic rocks and rocks torn from the walls of the diatreme. Etymology The name ''maar'' comes from a Moselle Franconian dialect word used for the circular lakes of the Daun area of Germany. The word evolved from its first use in German in the modern geological sense in 1819 and is now used in English and in the geological sciences as the term for the explosion crater, even if water from rainfall might alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lapilli
Lapilli (: lapillus) is a size classification of tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. ''Lapilli'' is Latin for "little stones". By definition lapilli range from in diameter. A pyroclastic particle greater than 64 mm in diameter is known as a volcanic bomb when molten, or a volcanic block when solid. Pyroclastic material with particles less than 2 mm in diameter is referred to as volcanic ash. Formation Lapilli are spheroid-, teardrop-, dumbbell- or button-shaped droplets of molten or semi-molten lava ejected from a volcanic eruption that fall to earth while still at least partially molten. These granules are the direct result of liquid rock cooling as it travels through the air. Lapilli tuffs are a very common form of volcanic rock typical of rhyolite, andesite and dacite pyroclastic eruptions, where thick layers of lapilli can be deposited during a basal surge eruption. Most lapilli tuf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Bomb
A volcanic bomb or lava bomb is a mass of partially molten rock (tephra) larger than 64 mm (2.5 inches) in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. Because volcanic bombs cool after they leave the volcano, they are extrusive igneous rocks. Volcanic bombs can be thrown many kilometres from an erupting vent, and often acquire aerodynamic shapes during their flight. Bombs can be extremely large; the 1935 eruption of Mount Asama in Japan expelled bombs measuring 5–6 m (16-20 ft) in diameter up to from the vent. Volcanic bombs are a significant volcanic hazard, and can cause severe injuries and death to people in an eruption zone. One such incident occurred at Galeras volcano in Colombia in 1993; six people near the summit were killed and several seriously injured by lava bombs when the volcano erupted unexpectedly. On July 16, 2018, 23 people were injured on a tour boat near the Kilauea volcano as a result of a baske ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phreatomagmatic Eruptions
Phreatomagmatic eruptions are volcanic eruptions resulting from interaction between magma and water. They differ from exclusively magmatic eruptions and phreatic eruptions. Unlike phreatic eruptions, the products of phreatomagmatic eruptions contain juvenile (magmatic) clasts.Heiken, G. & Wohletz, K. 1985. Volcanic Ash. University of California Press, Berkeley It is common for a large explosive eruption to have magmatic and phreatomagmatic components. Mechanisms Several competing theories exist as to the exact mechanism of ash formation. The most common is the theory of explosive thermal contraction of particles under rapid cooling from contact with water. In many cases the water is supplied by the sea, such as in the Surtsey eruption. In other cases the water may be present in a lake or caldera-lake, as at Santorini, where the phreatomagmatic component of the Minoan eruption was a result of both a lake and later the sea. There have also been examples of interaction between magm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanic Cone
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. Types of volcanic cones include stratocones, spatter cones, tuff cones, and cinder cones. Stratocone Stratocones are large cone-shaped volcanoes made up of lava flows, explosively erupted pyroclastic rocks, and igneous intrusives that are typically centered around a cylindrical vent. Unlike shield volcanoes, they are characterized by a steep profile and periodic, often alternating, explosive eruptions and effusive eruptions. Some have collapsed craters called calderas. The central core of a stratocone is commonly dominated by a central core of intrusive rocks that range from around to over several kilometers in diameter. This central core is surrounded by multiple generations of lav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeitschrift Für Geologische Wissenschaften
The ' () is a peer-reviewed German scientific journal established in 1973, that publishes preferably original papers in German and English dealing with geology and related sub-disciplines. Since 2005 the journal has been published bimonthly by the Verlag für Geowissenschaften Berlin. The journal was formerly an official periodical of the national East German Gesellschaft für Geologische Wissenschaften, the East German geological sciences society, and was published by the scientific and academic publishing house Akademie Verlag. The journal was regarded as the most important geological sciences periodical in East Germany with an international reputation. The journal is indexed in: GeoRef, Chemical Abstracts Service Chemical Abstracts Service (CAS) is a division of the American Chemical Society. It is a source of chemical information and is located in Columbus, Ohio, United States. Print periodicals ''Chemical Abstracts'' is a periodical index that provid ..., and Geoline. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disko Island
Disko Island (, ) is a large island in Baffin Bay, off the west coast of Greenland. It has an area of ,Norwegian University of Science and Technology making it the second largest island of Greenland (behind the main island), and one of the 100 largest islands in the world. It is part of the municipality, although it lies off the coast of southern Avannaata municipality, with mainland Qeqertalik a little to the south. Etymology The island's ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary
The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the Phanerozoic eon. It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene (2.58 million years ago to 11.7 thousand years ago) and the Holocene (11.7 thousand years ago to today); a proposed third epoch, the Anthropocene, was rejected in 2024 by IUGS, the governing body of the ICS. The Quaternary is typically defined by the Quaternary glaciation, the cyclic growth and decay of continental ice sheets related to the Milankovitch cycles and the associated climate and environmental changes that they caused. Research history In 1759 Giovanni Arduino proposed that the geological strata of northern Italy could be divided into four succ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smelting
Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron-making, iron, copper extraction, copper, silver mining#Ore processing, silver, tin, lead smelting, lead and zinc smelting, zinc. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal behind. The reducing agent is commonly a fossil-fuel source of carbon, such as carbon monoxide from incomplete combustion of coke (fuel), coke—or, in earlier times, of charcoal. The oxygen in the ore binds to carbon at high temperatures, as the Chemical energy, chemical potential energy of the bonds in carbon dioxide () is lower than that of the bonds in the ore. Sulfide ores such as those commonly used to obtain copper, zinc or lead, are roasting (metallurgy), roasted before smelting in order to convert the sulfid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
