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Winonaite
Winonaites are a group of primitive achondrite meteorites. Like all primitive achondrites, winonaites share similarities with chondrites and achondrites. They show signs of metamorphism, partial melting, brecciation and relic chondrules. Their chemical and mineralogical composition lies between H and E chondrites. Naming and history The winonaite group is named after the type specimen, the Winona meteorite. The name itself derived from Winona, Arizona where the type specimen was said to be found during an archaeological excavation of the Sinagua village Elden Pueblo in September 1928. The Sinagua lived in the village between 1150 and 1275. The meteorite was said to be retrieved from the cist of one of the rooms. However, a later study indicates the meteorite was found at another Sinagua site and not in Elden Pueblo.A. L. Christenson "J. W. Simmons' account of the discovery of the Winona meteorite."''Meteorite'' 10(3):14–16, 2004. As of 2021, 54 meteorites are included in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primitive Achondrite
Primitive achondrites are a subdivision of meteorites. They are classified on the same rank (historically called "Class") and lying between chondrites and achondrites. They are called primitive because they are achondrites that have retained much of their original chondritic properties. Very characteristic are relic chondrules and chemical compositions close to the composition of chondrites. These observations are explained as melt residues, partial melting, or extensive recrystallization. History The concept of primitive achondrites was first summarized in 1983. In 2006 a classification was published that assigned 7 groups to the primitive achondrites, but the classification remains controversial. The authors define primitive achondrites as meteorites "''that exceeded their solidus temperature on the parent body''" and thus would partially melt. Meteorites that have been fully melted are included if they did not reach isotopic equilibrium on their parent body. Description There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winona Meteorite
The Winona meteorite is a primitive achondrite meteorite. It is the type specimen and by far the largest meteorite of the winonaite group. Discovery and naming The Winona meteorite is named after Winona, Arizona. The meteorite is said to be discovered during an archaeological excavation of the Sinagua village Elden Pueblo in September 1928. The Sinagua lived in the village between 1150 and 1275. The meteorite was said to be retrieved from the cist of one of the rooms. In fact the meteorite was found at another Sinagua site and not in Elden PuebloA. L. Christenson "J. W. Simmons' account of the discovery of the Winona meteorite."''Meteorite''10(3):14-16, 2004 When the meteorite was removed from the cist it fell apart because it was badly weathered. The first description was made in 1929. The authors were of the opinion that the meteorite was too badly weathered to be accurately classified. They estimated that the meteorite was probably a mesosiderite. Mineralogy The meteorite co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IIICD Meteorites
IIICD meteorites are a group of primitive achondrites. They are classified in a clan together with the IAB meteorites and the winonaites. Description IIICD meteorites consists dominantly of meteoric iron with silicate inclusions. The silicate inclusions are almost identical to the IAB meteorite inclusions. They contain low-Ca pyroxene, high-Ca pyroxene, olivine, plagioclase, troilite, graphite, different phosphates, meteoric iron and traces of daubréelite and chromite. Parent body It has been established that IAB meteorites and winonaites originated from the same parent body. The same is not yet clear for IIICD meteorites, that originated from the same or a very similar asteroid. Classification The IIICD meteorites are classified as primitive achondrites because they have silicate inclusions and show signs of partial melting. The silicate inclusion are almost identical to silicate inclusions in IAB meteorites, and both are very similar to winonaites. For this reason all t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primitive Achondrite
Primitive achondrites are a subdivision of meteorites. They are classified on the same rank (historically called "Class") and lying between chondrites and achondrites. They are called primitive because they are achondrites that have retained much of their original chondritic properties. Very characteristic are relic chondrules and chemical compositions close to the composition of chondrites. These observations are explained as melt residues, partial melting, or extensive recrystallization. History The concept of primitive achondrites was first summarized in 1983. In 2006 a classification was published that assigned 7 groups to the primitive achondrites, but the classification remains controversial. The authors define primitive achondrites as meteorites "''that exceeded their solidus temperature on the parent body''" and thus would partially melt. Meteorites that have been fully melted are included if they did not reach isotopic equilibrium on their parent body. Description There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossary Of Meteoritics
This is a glossary of terms used in meteoritics, the science of meteorites. # * 2 Pallas – an asteroid from the asteroid belt and one of the likely parent bodies of the CR meteorites. * 4 Vesta – second-largest asteroid in the asteroid belt and likely source of the HED meteorites. * 221 Eos – an asteroid from the asteroid belt and one of the likely parent bodies of the CO meteorites. * 289 Nenetta – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * 3103 Eger – an asteroid from the asteroid belt and one of the likely parent bodies of the aubrites. * 3819 Robinson – an asteroid from the asteroid belt and one of the likely parent bodies of the angrites. * IA meteorite – an iron meteorite group now part of the IAB group/complex. * IAB meteorite – an iron meteorite and primitive achondrite of the IAB group/complex. * IB meteorite – an iron meteorite group now part of the IAB group/complex. * IC meteorite – an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achondrites
An achondrite is a stony meteorite that does not contain chondrules. It consists of material similar to terrestrial basalts or plutonic rocks and has been differentiated and reprocessed to a lesser or greater degree due to melting and recrystallization on or within meteorite parent bodies. As a result, achondrites have distinct textures and mineralogies indicative of igneous processes. Achondrites account for about 8% of meteorites overall, and the majority (about two-thirds) of them are HED meteorites, possibly originating from the crust of asteroid 4 Vesta. Other types include Martian, Lunar, and several types thought to originate from as-yet unidentified asteroids. These groups have been determined on the basis of e.g. the Fe/ Mn chemical ratio and the 17O/18O oxygen isotope ratios, thought to be characteristic "fingerprints" for each parent body. Classification Achondrites are classified into the following groups:O. Richard Norton. The Cambridge encyclopedia of meteorites. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Winona, Arizona
Winona is a small populated place in Coconino County in the northern part of the U.S. state of Arizona. At one time it was also called Walnut, and Winona's railroad station was renamed Darling in honor of an engineer. History Winona was once an incorporated village called Walnut Creek, until the 1950s when it became part of Flagstaff. Walnut Creek runs through Winona. It has been a dry creek bed since a dam was built above Walnut Canyon in the 1950s to provide Flagstaff with a reservoir. Before this, the creek ran year round. Railroad Winona train station was renamed on 6 December 1959 as "Darling" after William B. Darling, a local railroad engineer. Darling Cinder Pit to the north east of Winona and also named after him. The history of Darling is tied directly to the railroad that crosses through it. The Southwest Chief has been a regular visitor and for many years it was served by the Santa Fe Railway. In October 2019 a Burlington Northern freight train derailed there, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinagua
The Sinagua were a pre-Columbian culture that occupied a large area in central Arizona from the Little Colorado River, near Flagstaff, to the Verde River, near Sedona, including the Verde Valley, area around San Francisco Mountain, and significant portions of the Mogollon Rim country, between approximately . Since fully developed Sinagua sites emerged in central Arizona around 650 CE, it is believed they migrated from east-central Arizona, possibly emerging from the Mogollon culture. Name The name ''Sinagua'' was coined in 1939 by archaeologist Harold S. Colton,Gibbon 770 founder of the Museum of Northern Arizona, from the Spanish words ''sin'' meaning "without" and ''agua'' meaning "water", referring to the name originally given by Spanish explorers to the San Francisco Peaks near Flagstaff, the "Sierra Sin Agua". The name reflects the surprise the Spanish felt that such large mountains did not have perennial rivers flowing from them, as is common in Spain. Cultural phases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elden Pueblo
Elden Pueblo (Hopi: Pasiwvi) was a prehistoric Native American village located at the foot of Mount Elden near Flagstaff, Arizona. The pueblo is thought to have been part of a major trading system.Elden Pueblo Archaeological Site at Various trade items such as macaw skeletons from Mexico as well as from the coast of California have been found throughout the site. The area is now protected and is used for research and educational purposes. History ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cist
A cist ( or ; also kist ; from grc-gre, κίστη, Middle Welsh ''Kist'' or Germanic ''Kiste'') is a small stone-built coffin-like box or ossuary used to hold the bodies of the dead. Examples can be found across Europe and in the Middle East. A cist may have been associated with other monuments, perhaps under a cairn or long barrow. Several cists are sometimes found close together within the same cairn or barrow. Often ornaments have been found within an excavated cist, indicating the wealth or prominence of the interred individual. This old word is preserved in the Nordic languages as "" in Swedish and "" in Danish and Norwegian, where it is the word for a funerary coffin. In English it is related to "cistern".''cistern'' Regional examples ;Sri Lanka * Bellanbedipalassa * Pothana * Ibbankatuwa Megalithic Stones * Udaranchamadama ;England * Bellever Forest, Dartmoor * Hepburn woods, Northumberland ;Estonia * Jõelähtme (Rebala) stone-cist graves, Harju County ;Gu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrites
A chondrite is a stony (non-Metallicity, metallic) meteorite that has not been modified, by either melting or planetary differentiation, differentiation of the parent body. They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids. Some such bodies that are captured in the planet's gravity well become the most common type of meteorite by (whether quickly, or after many orbits) arriving on a trajectory toward the planet's surface. Estimates for their contribution to the total meteorite population vary between 85.7% and 86.2%. Their study provides important clues for understanding the origin and age of the Solar System, the synthesis of organic compounds, the Abiogenesis, origin of life and the presence of water on Earth. One of their characteristics is the presence of chondrules (from the Ancient Greek χόνδρος ''chondros'', grain), which are round grains formed as molten, or partially molten droplets, in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin Section
In optical mineralogy and petrography, a thin section (or petrographic thin section) is a thin slice of a rock or mineral sample, prepared in a laboratory, for use with a polarizing petrographic microscope, electron microscope and electron microprobe. A thin sliver of rock is cut from the sample with a diamond saw and ground optically flat. It is then mounted on a glass slide and then ground smooth using progressively finer abrasive grit until the sample is only 30 μm thick. The method uses the Michel-Lévy interference colour chart to determine thickness, typically using quartz as the thickness gauge because it is one of the most abundant minerals. When placed between two polarizing filters set at right angles to each other, the optical properties of the minerals in the thin section alter the colour and intensity of the light as seen by the viewer. As different minerals have different optical properties, most rock forming minerals can be easily identified. Plagioclase for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
