|
Suevite Aumühle
Suevite is a rock consisting partly of melted material, typically forming a breccia containing glass and crystal or lithic fragments, formed during an impact event. It forms part of a group of rock types and structures that are known as impactites. Name The word "suevite" is derived from "Suevia", Latin name of Swabia. The geologist Oliver Sachs was able to show that, over the course of the 19th and 20th centuries, this type of rock was recognized as something special and, in 1919, was formally introduced into petrographic science by Adolf Sauer under the name "suevite".J. O. Sachs: ''Wie der Schwabenstein zu seinem Namen kam.'' In: W. Rosendahl, M. Schieber (Hrsg.): ''Der Stein der Schwaben. Natur- und Kulturgeschichte des Suevits.'' Band 4, Staatsanzeiger-Verlag, Stuttgart 2009. Formation Suevite is thought to form in and around impact craters by the sintering of molten fragments together with unmelted clasts of the country rock. Rocks formed from more completely melted mater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traces Of Catastrophe
''Traces of Catastrophe: A Handbook of Shock-Metamorphic Effects in Terrestrial Meteorite Impact Structures'' is a book written by Bevan M. French of the Smithsonian Institution. It is a comprehensive technical reference on the science of impact craters. It was published in 1998 by the Lunar and Planetary Institute (LPI), which is part of the Universities Space Research Association (USRA). It was originally available in hard copy from LPI, but is now only available as a portable document format (PDF)This page uses the term PDF to mean either Portable Document Format for the e-book download, or planar deformation features for geological evidence of impact shock. e-book free download. The book has become very influential in the field of impact crater research, appearing as a common reference for papers and web sites on the topic. The Earth Impact Database lists it among the suggested reading on its introductory page about impact craters. The Impact Field Studies Group Impact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite Shock Stage
Meteorite shock stage is a measure of the degree of fracturing of the matrix of a common chondrite meteorite. Impacts on the parent body of a meteoroid can produce very large pressures. These pressures heat, melt and deform the rocks. This is called shock metamorphism. Meteorites are often given a rating from 1 to 6 showing the level of shock metamorphism. However, the degree of shock can vary within a meteorite on the scale of centimeters. Smaller bodies colliding with one another would not have sufficiently great impact velocity to produce the pressures and temperatures required to produce shock effects, due to their lesser gravitational attraction for one another. High instantaneous pressures, in excess of 5 Pascal (unit), GPa (1 GPa = 10,000 Atmosphere (unit), atmospheres), are necessary to produce shock metamorphism. Shock grade The fracturing of crystals and other features must be observed under a microscope with shock effects observed under polarized light. Larger struct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manicouagan Impact Structure
Manicouagan Reservoir (also Lake Manicouagan ; ) is an annular lake in central Quebec, Canada, covering an area of . The lake island in its centre is known as René-Levasseur Island, and its highest point is Mount Babel. The structure was created 214 (±1) million years ago, in the Late Triassic, by the impact of a meteorite in diameter. The lake and island are clearly seen from space and are sometimes called the "eye of Quebec". The lake has a volume of . Geography The reservoir is located in Manicouagan Regional County Municipality in the Côte-Nord region of Quebec, Canada, about north of the city of Baie-Comeau, although its northernmost part is located in Caniapiscau Regional County Municipality. Quebec Route 389 passes the eastern shore of the lake. The crater is a multiple-ring structure about across, with the reservoir at its diameter inner ring being its most prominent feature. It surrounds an inner island plateau called René-Levasseur Island and Mount Babel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rochechouart Impact Structure
Rochechouart impact structure or Rochechouart astrobleme is an impact structure in France. Erosion has over the millions of years mostly destroyed its impact crater, the initial surface expression of the asteroid impact, leaving highly deformed bedrock and fragments of the crater's floor as evidence of it. In 2008, the French State acknowledged the heritage value of the Rochechouart impact structure creating the “” on 12 sites representative of characteristic geological features of the impact structure. Location Named after the town of Rochechouart, the Rochechouart impact structure is located on the western margin of the French Massif Central near the city of Limoges, approximately south of Paris. Rochechouart (population about ) is built with rocks created or modified by the impact (impactites). Chassenon, a third of the size of Rochechouart, is also built of impactites. Impactite was used 2000 years ago for building Chassenon's monumental Roman baths of Cassinomagu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belarus
Belarus, officially the Republic of Belarus, is a landlocked country in Eastern Europe. It is bordered by Russia to the east and northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Belarus spans an area of with a population of . The country has a hemiboreal climate and is administratively divided into Regions of Belarus, six regions. Minsk is the capital and List of cities and largest towns in Belarus, largest city; it is administered separately as a city with special status. For most of the medieval period, the lands of modern-day Belarus was ruled by independent city-states such as the Principality of Polotsk. Around 1300 these lands came fully under the Grand Duchy of Lithuania and subsequently by the Polish–Lithuanian Commonwealth; this period lasted for 500 years until the Partitions of Poland, 1792-1795 partitions of Poland-Lithuania placed Belarus within the Belarusian history in the Russian Empire, Russian Empire for the fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logoisk Crater
Logoisk crater or Logoisk astrobleme is a meteorite impact crater in Belarus near the city of Lahoysk. It is in diameter and is estimated to be 42.3 ± 1.1 million years old (Eocene). The crater is not exposed at the surface. The crater was discovered by an accident during a routine exploration drilling near the village of in 1970s. A section was discovered with atypical materials in an unusual sequence: Quaternary deposits up to depth of 160m followed by a 230 meter thick layer of layered clays and lacustrine sediments followed by 240 meters of breccia Breccia ( , ; ) is a rock composed of large angular broken fragments of minerals or Rock (geology), rocks cementation (geology), cemented together by a fine-grained matrix (geology), matrix. The word has its origins in the Italian language ...s, rocks previously unseen in the geology of Belarus. Three more drills made in 1976-1977 provided a clear evidence of the meteorite origin of the anomaly. Subsequent drillings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gardnos Crater
Gardnos crater (''Gardnos krateret'') is a meteorite impact crater in Nesbyen municipality in Buskerud, Norway. It is located inside Meteorite Park (''Meteorittparken'') at Gardnos north of the town of Nesbyen. Gardnos crater is in diameter, and was created when a meteorite with an estimated diameter of struck 500 million years ago. At first this site was believed to be a volcanic crater, but in 1990 two geologists, Johan Naterstad and Johannes A. Dons, confirmed that it was in fact formed by meteorite impact. The original bedrock in the area was fractured and a powder of crushed rocks was forced into all the fractures. This is the origin of the peculiar rock in this area. It is possible to drive into the centre of the crater, which makes the Gardnos crater one of the world's most accessible meteorite craters. There are two trails through the surrounding natural region A natural region (landscape unit) is a basic geographic unit. Usually, it is a region which is distingu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kara Crater
Kara is a meteorite crater in the Yugorsky Peninsula, Nenetsia, Russia. Heavily eroded, it is presently in diameter, though it is thought to be originally before erosion. Its age is estimated to be 70.3 ± 2.2 million years old (Late Cretaceous). Impactite outcrops located on the Baydarata Gulf (Baydaratskaya) shore north-east of the crater imply that the original size of the crater could have been the 4th largest on Earth. The crater is not exposed at the surface. The Kara crater lies in the southeastern end of the Yugorsky Peninsula, while the Ust-Kara site lies offshore, east of the small Kara or Karskaya Guba inlet. It was formerly believed that these two sites were two separate craters and that they formed a twin impact structure from the Late Cretaceous. However, it seems that the Ust-Kara site does not exist as a separate site. Apparently, the suevite Suevite is a rock consisting partly of melted material, typically forming a breccia containing glass and crystal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chicxulub Crater
The Chicxulub crater is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is offshore, but the crater is named after the onshore community of Chicxulub Pueblo (not the larger coastal town of Chicxulub Puerto). It was formed slightly over 66 million years ago when an asteroid, about in diameter, struck Earth. The crater is estimated to be in diameter and in depth. It is believed to be the second largest impact structure on Earth, and the only one whose peak ring is intact and directly accessible for scientific research. The crater was discovered by Antonio Camargo and Glen Penfield, geophysicists who had been looking for petroleum in the Yucatán Peninsula during the late 1970s. Penfield was initially unable to obtain evidence that the geological feature was a crater and gave up his search. Later, through contact with Alan R. Hildebrand in 1990, Penfield obtained samples that suggested it was an impact feature. Evidence for the crater's imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popigai Impact Structure
The Popigai impact structure is the eroded remnant of an impact crater in northern Siberia, Russia. It is tied with the Acraman impact structure as the fourth largest verified impact structure on Earth. A large bolide impact created the crater approximately 35 million years ago during the late Eocene epoch ( Priabonian stage). It might be linked to the Eocene–Oligocene extinction event. The structure is east from the outpost of Khatanga and northeast of the city of Norilsk, NNE of the Anabar Plateau. It is designated by UNESCO as a Geopark, a site of special geological heritage. There is a small possibility that the Popigai impact crater may have formed simultaneously with the approximately 35-million-year-old Chesapeake Bay and Toms Canyon impact craters. For decades, the Popigai impact structure has fascinated paleontologists and geologists, but the entire area was completely off limits because of the diamonds found there. However, a major investigatory e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sudbury Basin
The Sudbury Basin (), also known as Sudbury Structure or the Sudbury Nickel Irruptive, is a major geology, geological structure in Ontario, Canada. It is among the oldest- and largest-known List of impact structures on Earth, impact structures on Earth. The structure, the eroded remnant of an Impact structure, impact crater, was formed by the impact of an asteroid 1.849 billion years ago in the Paleoproterozoic era. The ores of the Sudbury Basin are known to contain nickel, copper, gold, silver, platinum, palladium, rhodium, iridium, and ruthenium. The basin is located on the Canadian Shield in the city of Greater Sudbury, Ontario. The former municipalities of Rayside-Balfour, Valley East and Capreol lie within the Sudbury Basin, which is referred to locally as "The Valley". The urban core of the former city of Sudbury lies on the southern outskirts of the basin. An Ontario Historical Plaque was erected by the province to commemorate the discovery of the Sudbury Basin. Format ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
