File Rochechouart pseudo.jpg thumb 250px Pseudotachylite from the Rochechouart crater Rochechouart impact structure Pseudotachylite is a Fault geology Fault rock fault rock that has the appearance of the basaltic glass , tachylyte . It is dark in color and has a glassy appearance. However, the glass has normally been completely devitrified into very fine grained material with radial and concentric clusters of crystals. It may contain clasts of the country rock and occasionally crystals with quench textures that began to crystallize from the melt. ref http geology.geoscienceworld.org cgi content abstract 11 2 105 Maddock, R.H. 1983. Melt origin of fault generated pseudotachylites demonstrated by textures. Geology, 11, 105 108 ref Formation Seismic faulting It is generally found either along fault surfaces, often as the matrix geology matrix to a breccia , or as Vein geology veins injected into the walls of the fault. In most cases there is good evidence that the pseudotachylite formed by frictional melting of the wall rocks during rapid fault movement associated with a seismic event. ref http www3.interscience.wiley.com journal 119657427 abstract Sibson, R.H., 1975. Generation of pseudotachylite by ancient seismic faulting. Geophysical Journal of the Royal Astronomical Society 43, 775 ... 0CBEQ6AEwAg v onepage&q &f false accessdate 2009 11 02 isbn 9783540742357 ref The thickness of the pseudotachylite ... but lack clear indications of a melt origin. ref name Lin Landslides Pseudotachylite ..., the largest known landslide in history on land. Impact structures Pseudotachylite is also associated ... Publication, 140, 195 204. ref The pseudotachylite veins associated with impacts are much larger ..., Fiztgerald J.D. 1995 Large volumes of Anhydrous pseudotachylite in the Woodroffe Thrust, eastern ..., A.Y., Mernagh, T.P., 1990. Significance of pseudotachylite vein systems, Giles basic ultrabasic ... trip South Africa. Category Petrology Category Structural geology fr Pseudotachylite nl Pseudotachyliet ... more details
Yarrabubba crater refers to an impact structure or astrobleme , the eroded remnant of a former impact crater , situated in the northern Yilgarn Craton between the towns of Sandstone and Meekatharra , central Western Australia . ref name Macdonald etal 2003 Macdonald F.A., Bunting J.A. & Cina S.E. 2003. Yarrabubba a large, deeply eroded impact structure in the Yilgarn Craton, Western Australia. Earth and Planetary Science Letters 213, 235 247. http dx.doi.org 10.1016 S0012 821X 03 00322 4 Abstract ref ref name Bunting Macdonald 2004 Bunting J.A. & Macdonald F.A. 2004. The Yarrabubba structure, Western Australia clues to identifying impact events in deeply eroded ancient cratons. Geological Society of Australia Abstracts 73, 227. ref The original crater has been completely eroded and is not readily visible on aerial or satellite images the evidence for impact comes rather from the presence of shocked quartz and shatter cone s in outcrops of granite interpreted the be near the centre of the original crater, and from Geophysics geophysical data. The diameter of the original crater is uncertain, but has been estimated to be in the range convert 30 70 km mi abbr on . ref name Macdonald etal 2003 The age of the impact event is also uncertain, but it must be younger than the granite that has been shocked, which has been dated at about 2650 Annum Ma late Archaean . ref name Macdonald etal 2003 Veins of pseudotachylite rocks melted by friction in the granite have given a date of 1134 26 Annum Ma using the argon argon dating method, and although the significance of this age is not fully clear it is currently considered by some to provide the best tentative estimate for the age. ref name Pirajno 2005 Pirajno F. 2005. Hydrothermal processes associated with meteorite impact structures the evidence from three Australian examples and implications for economic resources. Australian Journal of Earth Sciences 52, 587 605. http journalsonline.tandf.co.uk link.asp?id gx253r5343746772 Ab ... more details
Image Brittle Ductile.gif thumb 450px Variation of strength with depth in continental crust and changes in dominant deformation mechanism s and fault rocks in a conceptual vertical Fault geology fault zone . The brittle ductile transition zone is the strongest part of the Crust geology Earth s crust . For quartz and feldspar rich rocks in continental crust this occurs at an approximate depth of 13 18 km roughly equivalent to temperatures in the range 250 400 C . At this depth rock becomes less likely to fracture , and more likely to deform Ductility ductilely by Creep deformation creep . This happens because the brittle strength of a material is increased by the confining pressure , whilst the ductile strength of a material decreases with increasing temperature. The transition zone occurs at the level in the crust where the downwards increasing brittle strength equals the upwards increasing ductile strength, giving a characteristic saw tooth crustal strength profile. This zone is, therefore, the strongest part of the crust and the depth at which many earthquakes occur. The level of the transition zone depends on both strain rate and temperature gradient, being shallower for slow deformation and or high heat flow and deeper for fast deformation and or low heat flow. Crustal composition will also affect the depth at which this zone occurs. Sections of fault zones once active in the transition zone, and now exposed at the surface, typically have a complex overprinting of brittle and ductile rock types. Cataclasite s or pseudotachylite breccias with mylonite clasts are common, as are ductily deformed cataclasites and pseudotachylites. ref http gsa.confex.com gsa 2006SE finalprogram abstract 102215.htm Adams, M. G. 2006. Alternating ductile brittle deformation in Alleghanian shear zones, northwestern North Carolina and eastern Tennessee. ref References reflist See also Seismogenic layer Ductility Ductile brittle transition temperature Ductile Brittle Transition Temp ... more details
Image Qu bec, Canada.svg right thumb 400px The Nastapoka arc is shown near the top, left portion of the province of Quebec in red . The Nastapoka arc is a geological feature located on the southeastern shore of Hudson Bay , Canada . It is a near perfect circular Arc geometry arc , covering more than 160 of a 450 km diameter circle. Due to its shape, the arc has long been suspected as the remnant of an ancient impact crater . ref name Beals 19968 Beals, C.S. 1968 On the possibility of a catastrophic origin for the great arc of eastern Hudson Bay. in C.S. Beals, ed., pp. 985 999, Science, history and Hudson Bay, vol. 2. Ottawa, Ontario, Canada Department of Energy, Mines and Resources. ref In August 1972, Dr. Robert S. Deitz and J. Paul Barringer conducted extensive search of much of the Nastapoka arc by Indian and Eskimo canoes and fishing boat in an investigation of its impact origin. They examined the abundant and extensive rock exposures that occur within the region of the Nastapoka arc and found a complete lack of shatter cones , suevite type or other unusual melt rocks, pseudotachylite or mylonite , radial faults or fractures, unusual injection breccia s, or any other evidence of shock metamorphism. ref name DeitzOthers 1973 Dietz, R.S., and J.P. Barringer 1973 Hudson Bay Arc as an Astrobleme a Negative Search. Meteoritics. 8 28 29. ref More commonly, it is regarded to be an arcuate boundary, which was created during the Trans Hudson orogeny , of tectonic origin between the Belcher Fold Belt and granitic rocks of the Superior Craton. ref name EatonOthers 2010a Eaton, D.W., and F. Darbyshire 2010 Lithospheric architecture and tectonic evolution of the Hudson Bay region. Tectonophysics. v. 480, pp. 1 22. ref ref name Hynes 1991 Hynes, A.J. 1991 The gravity field of eastern Hudson Bay Evidence for a flexural origin for the Hudson Bay Nastapoka arc? Tectonics. 10 722 728. ref References Reflist Coord 56 50 N 78 20 W display title type waterbody region CA QC sca ... more details
File Suevit Rochechouart.jpg thumb Greenish suevite from an impact crater at Rochechouart , France File Suevite.jpg thumb Suevite from the N rdlinger Ries impact crater File Suevit Logoisk.jpg thumb Suevite from an impact crater at Lahojsk , Belarus File Suevit Manicouagan.jpg thumb Suevite from the Manicouagan crater , Quebec, Canada File Suevite Aum hle.jpg thumb A thick layer of suevite light gray over blocks of Bunte Breccia here mostly made up of reddish clay File N rdlingenRathausTreppenportal.jpg thumb Portal to the town hall s stairway made of suevite in N rdlingen , Germany Suevite is a Rock geology rock consisting partly of melted material, typically forming a breccia containing glass and crystal or Lithic fragment geology lithic fragments, formed during an Impact crater impact event. It forms part of a group of rock types and structures that are known as impactite s. 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. Wholesale melt rocks found in the crater floor are known as tagamites . Suevite is distinct from the pseudotachylite in an impact structure as the latter is thought to have formed by frictional effects within the crater floor and below the crater during the initial compression phase of the impact and the subsequent formation of the central uplift. ref French, B.M. 1998. Traces of Catastrophe , A handbook of shock metamorphic effects in terrestrial meteorite impact structures, Lunar and Planetary Institute http www.lpi.usra.edu publications books CB 954 chapter5.pdf Chapter 5 . PDF . Retrieved on 2011 06 22. ref Occurrence Suevite is one of the diagnostic rock types for large impact structures. It has been described from many of the larger impact structures identified on earth. N rdlinger Ries ref Baier, J. 2009. http www.ogv online.de Publikationen Jahresberichte 2009 nf91 1.html Zur Herkunft und Bedeutung der Ries Auswurfprodukte f r den Im ... more details
shear texture and into mylonite zones. Within the depth range of 5 10 km pseudotachylite ... into discrete fault planes. Frictional heating in this case may melt the rock to form pseudotachylite ... more details
image boudin vein.jpg thumb right Boudinage d quartz vein with strain fringe showing Fault geology sinistral shear sense , Starlight Pit, Fortnum Gold Mine, Western Australia Shear is the response of a rock to Deformation engineering deformation usually by compressive stress and forms particular textures. Shear can be homogeneous or non homogeneous, and may be pure shear or simple shear . Study of geological shear is related to the study of structural geology , rock microstructure or List of rock textures rock texture and geological fault fault mechanics . The process of shearing occurs within brittle, brittle ductile, and ductile rocks. Within purely brittle rocks, compressive stress results in fracturing and simple geological fault faulting . Rocks Rocks typical of shear zones include mylonite , cataclasite , Tectonite S tectonite and Tectonite L tectonite , pseudotachylite , certain breccia s and highly foliated versions of the wall rocks. Shear zone keep this name the same or change the Shear zone redirect Image Asymmetric shear.jpg thumb Asymmetric shear in basalt, Labouchere mine, Glengarry Basin, WA. Shear asymmetry is dextral, pen for scale For a more detailed article see Shear zone A shear zone is a tabular to sheetlike, planar or curviplanar zone composed of rocks that are more highly strained than rocks adjacent to the zone. Typically this is a type of geologic fault fault but it may be difficult to place a distinct fault plane into the shear zone. Shear zones may form zones of much more intense foliation geology foliation , Deformation engineering deformation , and fold geology folding . En echelon veins or fractures may be observed within shear zones. Many shear zones host ore deposits as they are a focus for hydrothermal flow through orogeny orogenic belts . They may often show some form of retrograde metamorphism from a peak metamorphic assemblage and are commonly metasomatism metasomatised . Shear zones can be only inches wide, or up to several kilom ... more details
Wiktionary pipe clast clast Image LvMS Lvm.jpg thumb A thin section of a clast sand grain , derived from a basalt scoria . Vesicular texture Vesicles air bubbles can be seen throughout the clast. Plane light above, cross polarized light below. Scale box is 0.25 mm Clastic rocks are composed of fragments, or clasts , of pre existing Rock geology rock . Geologists use the term clastic with reference to sedimentary rock s as well as to particles in sediment transport whether in suspension or as bed load , and in sediment deposits. Clastic metamorphic and igneous rocks Clastic metamorphic rocks include breccia s formed in Fault geology Fault rock fault s, as well as some mylonite protomylonite and pseudotachylite . Occasionally, metamorphic rocks can be brecciated via hydrothermal fluids, forming a hydraulic fracture hydrofracture breccia. Clastic igneous rocks include pyroclastic volcanic rock s such as tuff , agglomerate and intrusive breccia s, as well as some marginal eutaxitic and taxitic intrusive morphologies. Igneous clastic rocks are broken by flow, injection or explosive disruption of solid or semi solid igneous rocks or lava s. Clastic sediments Image GLMsed.jpg thumb 250px Claystone from Montana Clastic sedimentary rock s are rocks composed predominantly of broken pieces or clasts of older weathering weathered and erosion eroded rocks. Clastic sediments or sedimentary rocks are classified based on Particle size grain size , clast and cementing material Matrix geology matrix composition, and texture. The classification factors are often useful in determining a sample s Sedimentary depositional environment environment of deposition . An example clastic environment would be a river system in which the full range of grains being transported by the moving water consist of pieces erosion eroded from solid rock upstream. Grain size determines the basic name of a clastic sedimentary rock. Grain size varies from clay in shale s and claystone s through silt in siltsto ... more details
class ombox notice align right style margin left 0.6em style background eeeefd colspan 4 center Greek alphabet center colspan 4 center Transliteration schemes center style background e1e1e1 Greek Traditional Classical Modern a a a b b v g g gh, y d d dh e e e z z, dz z e i th th th i i i c k k l l l m m m n n n x x x o o o p p p r r r s s s t t t y u i ph ph ph, f ch kh kh ps ps ps o o ae, e ai e, ai au au af, av i ei i eu eu ef, ev ng ng ng nx nx nx nc nk g, ng nch nkh nkh mp mp b, mb nt nt d, nd oe, e oi i u ou ou, u Expand list date August 2008 This is a list of Greek words with derivatives in English . The words are in Greek alphabetic order, with tables for the 24 Greek letters, listing thousands of related English words. table id toc border 0 tr th Contents tr td Transliteration Transliteration Greek words with modern derivatives Greek Words with Modern Derivatives See also See also External links External links table NOTOC Transliteration There are considerable differences between the various transliteration s used to represent the Greek alphabet in English Language English . The table in the sidebar shows The traditional transliteration, in other words that used in Latin , representing classical Greek this is the form in which most Greek words have made their way into English A classical transliteration, commonly used to represent more accurately the pronunciation of Ancient Greek, although traditional forms are rarely used. The modern transliteration often used for Modern Greek see transliteration of Greek into English for some variations. Rough breathing was represented in some Greek dialects by an h while in others, the h represented the vowel eta the origin of the sign is thought to be the left hand half of the letter H a ro ... more details
ABOUT this was originally Talk English words with uncommon properties Containing all the vowel, but mature now. main English words with uncommon properties Containing all the vowels This article is part of a series of English words with uncommon properties and list all 2880 English words in wiktionary en containing all the vowels with the exception of terms comprising spaces e.g. phrases , ignoring accents a and splitting ligature ae class wikitable sortable link id size wikt eunoia n 6 wikt aerious adj 7 wikt eutopia n 7 wikt Eutopia n 7 wikt isourea n 7 wikt sequoia n 7 wikt aboideau n 8 wikt aboiteau n 8 wikt quison n 8 wikt aequorin n 8 wikt anemious adj 8 wikt autocide n 8 wikt autofire n 8 wikt autohide v 8 wikt avenious adj 8 wikt caesious adj 8 wikt dialogue n v 8 wikt edacious adj 8 wikt equation n 8 wikt euphobia n 8 wikt euphoria n 8 wikt euryopia n 8 wikt eusocial adj 8 wikt exonumia n 8 wikt jalousie n 8 wikt outraise v 8 wikt poulaine n 8 wikt quaestio n 8 wikt sequoian adj 8 wikt thiourea n 8 wikt utopiate n 8 wikt abreuvoir n 9 wikt acuminose adj 9 wikt aleuronic adj 9 wikt aliferous adj 9 wikt aliquoted adj 9 wikt andouille n 9 wikt aneuploid adj n 9 wikt arsenious adj 9 wikt audiotape n v 9 wikt aureation n 9 wikt auriscope n 9 wikt authorize v 9 wikt autocrime n 9 wikt autocrine adj 9 wikt autogenic adj 9 wikt autotelic adj 9 wikt azorubine n 9 wikt behaviour n 9 wikt cauponize v 9 wikt cautioner n 9 wikt damourite n 9 wikt deiparous adj 9 wikt education n 9 wikt emulation n 9 wikt equimolar adj 9 wikt equivocal n adj 9 wikt Euamerion proper 9 wikt euatmotic adj 9 wikt eudemonia n 9 wikt euphorbia n 9 wikt Euphorbia n 9 wikt exudation n 9 wikt facetious adj 9 wikt favourite adj n v 9 wikt feracious adj 9 wikt gigajoule n 9 wikt guanodine n 9 wikt guanosine n 9 wikt housemaid n v 9 wikt inoculate v 9 wikt isobutane n 9 wikt jailhouse n 9 wikt jalousied adj 9 wikt ketonuria n 9 wikt Labourite n 9 wikt limaceous adj 9 wikt meiofauna n 9 wikt mic ... more details
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