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Moldavite
Moldavite () is a forest green, olive green or blue greenish vitreous silica projectile glass formed by a meteorite impact in southern Germany ( Nördlinger Ries Crater) that occurred about 15 million years ago. It is a type of tektite and a gemstone. Material ejected from the impact crater includes moldavite, which was strewn across parts of Germany, the Czech Republic and Austria. Early studies Moldavite was introduced to the scientific public for the first time in 1786 as "chrysolites" from Týn nad Vltavou in a lecture by Josef Mayer of Prague University, read at a meeting of the Bohemian Scientific Society (Mayer 1788). Zippe (1836) first used the term "moldavite", derived from the Vltava (Moldau) river in Bohemia (the Czech Republic), from where the first described pieces came. Origin In 1900, Franz Eduard Suess pointed out that the gravel-size moldavites exhibited curious pittings and wrinkles on the surface, which could not be due to the action of water, but resemble ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tektite
Tektites () are gravel-sized bodies composed of black, green, brown or grey natural glass formed from terrestrial debris ejected during meteorite impacts. The term was coined by Austrian geologist Franz Eduard Suess (1867–1941), son of Eduard Suess. They generally range in size from millimetres to centimetres. Millimetre-scale tektites are known as microtektites.French, B. M. (1998) ''Traces of Catastrophe: A Handbook of Shock-Metamorphic Effects in Terrestrial Meteorite Impact Structures.'' LPI Contribution No. 954. Lunar and Planetary Institute, Houston, Texas. 120 pp.McCall, G. J. H. (2001) ''Tektites in the Geological Record: Showers of Glass from the Sky.'' The Geological Society Publishing House, Bath, United Kingdom. 256 pp. Montanari, A., and C. Koeberl (2000) ''Impact Stratigraphy. The Italian Record.'' Lecture Notes in Earth Sciences Series no. 93. Springer-Verlag, New York, New York. 364 pp. Tektites are characterized by: # a fairly homogeneous composition # an ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nördlinger Ries
The Nördlinger Ries is an impact crater and large circular depression in western Bavaria and eastern Baden-Württemberg. It is located north of the Danube in the district of Donau-Ries. The city of Nördlingen is located within the depression, about south-west of its centre. Etymology "Ries" is derived from Raetia, since the tribe of Raetians lived in the area in pre- Roman times. Description The depression is a meteorite impact crater formed 14.808 ± 0.038 million years ago in the Miocene. The crater is most commonly referred to simply as the ''Ries crater'' or ''the Ries''. The original crater rim had an estimated diameter of . The present floor of the depression is about below the eroded remains of the rim. It was originally assumed that the Ries was of volcanic, glacial or tectonic origin. Oliver Sachs introduced, in this context, the term "pioneer era" (up to 1870) and marked the beginning of early modern research on the Ries (from 1870), meaning the perio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franz Eduard Suess
Eduard Suess (; 20 August 1831 – 26 April 1914) was an Austrian geologist and an expert on the geography of the Alps. He is responsible for hypothesising two major former geographical features, the supercontinent Gondwana (proposed in 1861) and the Tethys Ocean. Biography Eduard Suess was born on 20 August 1831 in London, England, the oldest son of Adolph Heinrich Suess, a Lutheran Saxon merchant, and mother Eleonore Friederike Zdekauer. Adolph Heinrich Suess was born on 11 March 1797 in Saxony and died on 24 May 1862 in Vienna; Eleonore Friederike Zdekauer was born in Prague, now part of the Czech Republic, which once belonged to the Holy Roman Empire and the Austrian Empire. When Eduard Suess was an infant, his family relocated to Prague, and then to Vienna when he was 14. He became interested in geology at a young age. At the age of 19, while working as an assistant at the Hofmuseum in Vienna, he published his first paper—on the geology of Carlsbad (now Karlovy Vary in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Týn Nad Vltavou
Týn nad Vltavou (; ) is a town in České Budějovice District České Budějovice District () is a Okres, district in the South Bohemian Region of the Czech Republic. Its capital is the city of České Budějovice. Administrative division České Budějovice District is divided into three Districts of the Cz ... in the South Bohemian Region of the Czech Republic. It has about 7,800 inhabitants. It lies on the Vltava river. The historic town centre is well preserved and is protected as an Cultural monument (Czech Republic)#Monument zones, urban monument zone. Administrative division Týn nad Vltavou consists of eight municipal parts (in brackets population according to the 2021 census): *Týn nad Vltavou (4,407) *Hněvkovice na levém břehu Vltavy (67) *Koloděje nad Lužnicí (189) *Malá Strana (2,610) *Netěchovice (106) *Nuzice (113) *Předčice (74) *Vesce (36) Etymology The Old Czech word ''týn'' is related to English 'Town#Origin and use, town'. It was a term for a fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope
Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemical element), but different nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties. The term isotope is derived from the Greek roots isos (wikt:ἴσος, ἴσος "equal") and topos (wikt:τόπος, τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd (doctor), Margaret Todd in a 1913 suggestion to the British chemist Frederick Soddy, who popularized the term. The number of protons within the atomic nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheb Basin
Cheb (; ) is a town in the Karlovy Vary Region of the Czech Republic. It has about 33,000 inhabitants. It lies on the Ohře River. Before the expulsion of Germans in 1945, the town was the centre of the German-speaking region known as Egerland. The historic town centre is well preserved and is protected as an urban monument reservation. Administrative division Cheb consists of 19 municipal parts (in brackets population according to the 2021 census): *Cheb (26,768) *Bříza (47) *Cetnov (104) *Chvoječná (28) *Dolní Dvory (49) *Dřenice (50) *Háje (1,082) *Horní Dvory (57) *Hradiště (206) *Hrozňatov (209) *Jindřichov (86) *Klest (41) *Loužek (23) *Pelhřimov (95) *Podhoří (142) *Podhrad (665) *Skalka (228) *Střížov (172) *Tršnice (109) Etymology The first name of the town, documented in 1061, was ''Egire''. It was a Latin name, which was derived from the Celtic name of the Ohře River ''Agara''. The German name ''Eger'' was then derived from the Latin name. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lusatia
Lusatia (; ; ; ; ; ), otherwise known as Sorbia, is a region in Central Europe, formerly entirely in Germany and today territorially split between Germany and modern-day Poland. Lusatia stretches from the Bóbr and Kwisa rivers in the east to the Pulsnitz and Black Elster rivers in the west, and is located within the German states of Saxony and Brandenburg as well as in the Polish voivodeships of Lower Silesia and Lubusz. Major rivers of Lusatia are the Spree and the Lusatian Neisse, which defines the border between Germany and Poland. The Lusatian Mountains of the Western Sudetes separate Lusatia from Bohemia (Czech Republic) in the south. Lusatia is traditionally divided into Upper Lusatia, the hilly southern part, and Lower Lusatia, the flat northern part. The areas east and west along the Spree in the German part of Lusatia are home to the Slavic Sorbs, one of Germany’s four officially recognized indigenous ethnic minorities. The Upper Sorbs inhabit Saxon U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waldviertel
The ''Waldviertel'' (; ; Central Bavarian: ; ) is the northwestern region of the Austrian state of Lower Austria. It is bounded to the south by the river Danube, to the southwest by Upper Austria, to the northwest and to the north by the Czech Republic and to the east by the Manhartsberg (), which is the survey point dividing the from the region. Geologically it is part of the Bohemian Massif. In the south are the Wachau and Kamptal wine regions. Districts The following administrative districts of Lower Austria are considered to be part of the * * * * * * northern part of * statutory city of Krems an der Donau Economy The northern Waldviertel (Forest Region) had been part of the Bohemian region of glasshouses since the 14th century. In historical times, Waldviertel sands were good raw materials for forest glass production, especially for colored glass. Further reading * Birgit Zotz Birgit Zotz (born 7 August 1979) is an Austrian writer, cultural anthropo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window panes, tableware, and optics. Some common objects made of glass are named after the material, e.g., a Tumbler (glass), "glass" for drinking, "glasses" for vision correction, and a "magnifying glass". Glass is most often formed by rapid cooling (quenching) of the Melting, molten form. Some glasses such as volcanic glass are naturally occurring, and obsidian has been used to make arrowheads and knives since the Stone Age. Archaeological evidence suggests glassmaking dates back to at least 3600 BC in Mesopotamia, Ancient Egypt, Egypt, or Syria. The earliest known glass objects were beads, perhaps created accidentally during metalworking or the production of faience, which is a form of pottery using lead glazes. Due to its ease of formability int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryllium-10
Beryllium-10 (10Be) is a radioactive isotope of beryllium. It is formed in the Earth's atmosphere mainly by cosmic ray spallation of nitrogen and oxygen. Beryllium-10 has a half-life of 1.39 million years, and decays by beta decay to stable boron-10 with a maximum energy of 556.2 keV. It decays through the reaction 10Be→10B + e−. Light elements in the atmosphere react with high energy galactic cosmic ray particles. The spallation of the reaction products is the source of 10Be (t, u particles like n or p): :14N(t,5u)10Be; Example: 14N(n,p α)10Be :16O(t,7u)10Be Because beryllium tends to exist in solutions below about pH 5.5 (and rainwater above many industrialized areas can have a pH less than 5), it will dissolve and be transported to the Earth's surface via rainwater. As the precipitation quickly becomes more alkaline, beryllium drops out of solution. Cosmogenic 10Be thereby accumulates at the soil surface, where its relatively long half-life (1.387 million years) p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australite
Australites are tektites found in Australia. They are mostly dark or black, and have shapes including discs and bowls that are not seen in other tektites. NASA used the shape of "flanged button" australites in designing re-entry modules for the Apollo program in the 1960s. History Indigenous Australians from the Diyari group termed australites ' ("staring eyes"), and they were used as sacred objects or as cutting tools. Europeans found out about australites in 1857, when explorer Thomas Mitchell gave naturalist Charles Darwin a mysteriously shaped piece of natural black glass. Darwin thought that australites were of volcanic origin due to their similarity to obsidian, volcanic glass. Later, australites were called ''blackfellows' buttons'' and ''obsidian bombs''. One of the first scientists to seriously study australites was Charles Fenner, who saw his first australite in 1907. He believed that australites were glass meteorites. Origin Early theories about the source of austral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
