Search: in
Craton
Craton in Encyclopedia Encyclopedia
  Tutorials     Encyclopedia     Videos     Books     Software     DVDs  
       
Encyclopedia results for Craton
Craton Email this to a friend      Craton

Craton





Encyclopedia results for Craton

  1. Craton

    World geologic provinces A craton lang el kratos strength is an old and stable part of the continental lithosphere . Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates. They are characteristically composed of ancient crystalline basement rock , which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots that extend as much as a few hundred kilometers into the Earth s mantle geology mantle . The term craton is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons can be described as Shield geology shields , in which the basement rock crops out at the surface, and Platform geology platforms , in which the basement is overlain by sediments and sedimentary rock. The word craton was first ... term to kraton and then to craton. Examples of cratons are the Slave craton in Canada, the Wyoming craton in the United States, the Amazonian shield Amazonia craton in South America, and the Kaapvaal craton in South Africa. Provinces Cratons are subdivided geographically into geologic province .... ref name SN24 Petit 2010 p.24 ref At that depth, craton roots extend into the asthenosphere . ref name SN24 Craton lithosphere is distinctly different from oceanic lithosphere because cratons have ... increases due to geothermal contraction and prevents the craton from sinking into the deep mantle ... rock subvolcanic pipes called kimberlite s. These inclusions have densities consistent with craton .... Peridotite is strongly influenced by the inclusion of moisture. Craton perodotite moisture content ... lodged beneath a proto craton in an under plating process, 3 accretion from island arcs or continental fragments rafting together to thicken into a craton. ref name SN26 Petit 2010 p.26 ref Earth ... de Kraton et Kraaton es Crat n eo Kratono eu Kratoi fr Craton it Cratone he ka kk ...   more details



  1. Sclavia craton

    Unreferenced stub auto yes date December 2009 Orphan date December 2009 A Sclavia craton is a late Archean super craton thought to be parental to the Slave craton . The shape and size of this supercraton are currently unknown. DEFAULTSORT Sclavia Craton Category Cratons Category Historical geology Palaeo geo stub ...   more details



  1. Sebakwe craton

    The Sebakwe proto craton is a hypothesized earlier formation of the Zimbabwe craton . A single Early Archaean continental crust al segment existed in Zimbabwe , extending for over 450 km from the south central Tokwe region, through the Midlands and up to the northern Shamva region of the present day craton . This c.3.4 Ga Crust geology crust al block, which we propose to be called the Sebakwe Proto craton, stabilised around 3.35 Ga with a later granitoid emplacement event around 3.2 Ga and provided the basement for the 3.0 2.6 Ga Late Archaean granite greenstone belt greenstone magma tism. Nesbitt et al., 1999 References Nesbitt, Robert W., Stephen N. Noble, and James F. Wilson. 1999 The Sebakwe Proto Craton An Extensive Early Archaean Crustal Block in Zimbabwe A Reassessment of Craton Formation, Stabilisation and Growth. Journal of Conference Abstracts, Vol. 4 No. 1, Symposium A08, Early Evolution of the Continental Crust. Online http www.the conference.com JConfAbs 4 140.html Category Cratons Category Geology of Africa Category Geology of Zimbabwe Category Geology of Zambia Geology stub lv Sebakves kratons ...   more details



  1. Kalahari craton

    of Mesoproterozoic older than 1.3  Ga cratons in South America and Africa. The Kalahari craton is a craton , an old and stable part of the continental lithosphere with thick crust and deep lithospheric ... a large portion of South Africa and consists of the Kaapvall craton Kaapvaal , the Zimbabwe craton , the Limpopo belt , and the Namaqua Belt . Geology Kalahari craton has formed a stable ... was formed and reworked along all of the craton s margins at 1.4 1.0 Ga. To the north, the Damara Lufilian Zambezi Fold Belt separates the Congo craton to the north with the Kalahari. Central Zambia exhibits ... zone between the Congo craton to the north and the Kalahari. The Zambezi Belt and the Lufilian Arc ... 03.pdf ref Pan African belts along the northern and eastern craton margins are associated in one ... north of the Kalahari craton and east of the Congo craton that includes large amounts of 1.15 1.0 Ga ... orthogneisses within Widespread intraplate magmatism affected much of the Kalahari craton at 1.1 Ga ... Belt also joins the Zimbabwe craton to the north with the Kaapvaal craton to the south. The belt ... s. Kalahari craton with Laurentia, Rodinia, and Gondwana Early Paleomagnetism paleomagnetic ... over a large part of the Kalahari craton, and also a detached fragment now located in East Antarctica ... with the geochronology. The pole position places the Kalahari craton off southeast Laurentia ... craton probably converged with southwestern Laurentia between 1060 and 1030 Ma to become part of the Rodinia supercontinent by 1000 Ma. In Rodinia, the Kalahari craton lay near East Antarctica with the Namaqua Natal orogenic belt facing outboard and away from the Laurentian craton. ref Jone, D.L., S. Pisarevsky ... Craton in Rodinia http 72.14.253.104 search?q cache 1rUf9urzSugJ www.tsrc.uwa.edu.au data page ... of Rodinia. ref Hanson, R.E. 2004 Mesoproterozoic Tectonic Evolution of the Kalahari Craton Implications ... between the Kalahari craton and a composite Congo Laurentia craton during the assembly ...   more details



  1. Congo craton

    unreferenced date March 2008 Image Cratons West Gondwana.svg thumb right Approximate location of Mesoproterozoic older than 1.3  Ga cratons in South America and Africa. The Congo craton , covered by the Palaeozoic to recent Congo basin , is an ancient Precambrian craton that with four others the Kaapvaal craton Kaapvaal , Zimbabwe craton Zimbabwe , Tanzania, and West African craton s makes up the modern continent of Africa . These cratons were formed between about 3.6 and 2.0 billion years ago and have been tectonic ally stable since that time. All of these cratons are bounded by younger fold belts formed between 2.0 billion and 300 million years ago. The Congo craton occupies a large part of central southern Africa, extending from the Kasai region of the Democratic Republic of the Congo DRC into Sudan and Angola . It forms parts of the countries of Gabon , Cameroon , and the Central African Republic . A small portion extends into Zambia as well, where it is called the Bangweulu Block . In Late Neoproterozoic time, the Congo craton was a low lying platform the size of the conterminous United States . It was blanketed by limestone carbonate s and shale s containing regionally mappable diamictite horizons of Glacier glacial origin. See also Supercontinent Major African geological formations Continents of the world Category Historical continents Category Cratons Category Geology of Africa tectonics stub palaeo geo stub it Cratone del Congo lv Kongo kratons nl Nigerblok pl Kraton Konga zh ...   more details



  1. Churchill craton

    half of the Western Churchill Craton, near Uranium City, Saskatchewan consists of a mixed ... Churchill craton. The Taltson Basement rock basement ca. 3.2 3.0 Ga and 2.4 2.14 Ga and Rutledge ... drilling in the south Slave Province, NWT, Churchill craton at the northwest corner of the Hudson Bay and in Ontario . The Northwest Territories NWT , North Slave craton and Keewatin Region, Nunavut ... by diamond friendly cratonic rocks of the Slave craton, Churchill craton and the Buffalo Head craton ... the Slave craton, which is covered with shallow lakes and swamp, the eastern part of the Churchill craton ... craton, which is serviced by the fully developed infrastructure of Yellowknife . The Eastern Arctic ... by barge during summer. See also Rae craton Superior craton References Sandeman, H.A. 2001 Ar Ar Geochronological ...   more details



  1. Wyoming craton

    Hearne Rae craton Rae and Superior craton Superior craton s pink that constitute the central core of the North American craton Laurentia . Image North america craton nps.gif thumb 300 px The North America n craton, also called Laurentia . The Wyoming craton is a craton located in the west central ... core of the continental crust of North America . The Wyoming craton was Suture geology sutured together with the Superior craton Superior and Hearne craton Hearne Rae craton Rae cratons in the Orogeny ... of the Wyoming Craton Implications for the Tectonic and Magmatic Evolution of the Northern Rocky Mountains ... into younger plutons indicates that the Wyoming craton was, and still is, a 100,000  km sup 2 sup middle Archean craton that was modified by late Archean magmatism and tectonism and Proterozoic ... assembly of the eastern Wyoming craton with Laurentia began during the ca. 1.78 1.74 Ga interval ... craton. ref name Dahl cite journal author Dahl, Peter S., Daniel K. Holm, Edward T. Gardner, Fritz ... craton province , the Paleoproterozoic Trans Hudson orogen, and the Paleoproterozoic Colorado orogeny . The Colorado orogen collided with the Wyoming craton at 1.78 1.75 Ga. Collision of the Colorado orogen and the Trans Hudson orogen with the Archean craton produced strong structural overprinting along the southern and eastern margins of the Wyoming craton. The Wyoming craton consists mainly of two ... as part of what is now the Wyoming craton. Subsequent to amalgamation of the Wyoming crust to Laurentia ... Mueller, P A. and C.D. Frost year 2006 title The Wyoming Province a distinctive Archean craton in Laurentian ... to the 3.0 Ga craton, 4 the Sierra Madre Medicine Bow block, and 5 the Black Hills Hartville block. Based ... the Colorado orogeny accreted to the Wyoming craton along the Cheyenne belt , a 500 km wide belt ... from the suture marked by the Laramie Mountains. Collision along the east margin of the craton with the Paleoproterozoic ... throughout the Colorado orogen. ref name Sims The Wyoming craton owes its spectacular mountainous ...   more details



  1. Sarmatian craton

    File Ukraine geology.png 250px thumb 10. Sarmatian craton Sarmatian craton is a geology geological and tectonics term for the southern segment region of the East European craton also known as Scythian plateau . The craton contains Archaean rocks 2.8 to 3.7 billion years old. During the Carboniferous Period the craton was rift ed apart by the Dneiper Donets rift . As a result, geomorphologically the cratonic area is split by the Donbass Fold Belt, also known as a part of the large Pripyat Dniepr Donets aulacogen , which transects Sarmatia, dividing it into the Ukrainian Massif or shield on the southwest and the Voronezh Massif to the northeast. Sarmatia is made up of several once independent Archaen land masses that developed at 3.7 2.9, 3.2 3.0, and 2.7 Ga. 2.3 2.1 Ga orogenic belts now separate these land masses. Sarmatia s northwestern margin has an extensive continental magmatic arc dating back to 2.0 Ga. At 200 Ma Sarmatia collided with Fennoscandia. References Bogdanova, Svetlana V. 2005 The East European Craton Some Aspects of the Proterozoic Evolution in its South West. Polskie Towarzystwo Mineralogiczne Prace Specjalne Mineralogical Society of Poland Special Papers, Zeszyt 26, 2005 Vol. 26. Online http www.geo.uw.edu.pl PTMINSP 2005 018.pdf http www.geofys.uu.se eprobe Projects ebridge ep eubr.pdf Svetlana Bogdanova Lund and EUROBRIDGE, Palaeoproterozoic Accretion of Sarmatia and Fennoscandia http www.geol.uniovi.es TDG Volumen25 TG25 06.PDF Dmitry A. Ruban and Shoichi Yoshioka, Late Paleozoic Early Mesozoic Tectonic Activity within the Donbass Russian Platform Category Cratons Category Geography of Ukraine Category Landforms of Europe geology stub pl Sarmacja kraton ru uk ...   more details



  1. Rae craton

    image North america basement rocks.png right thumb 250px North America cratons and basement rock. The Rae craton is an Archean craton located in northern Canada north of the Superior craton . Ungava Peninsula The Ungava Peninsula , situated on the northeast portion of the Canadian Shield , is where the Rae Province connects with the Superior Province. The area is composed of Archean rocks ca. 2.7 2.9 Ga from the Douglas Harbour Domain see Superior craton . The Archean rocks are overlain by Paleoproterozoic supracrustal Sequence geology sequences ca. 1.8 2.1 Ga and intrusion intruded by Paleoproterozoic diabase Dike geology dykes ca.2.0 2.2 Ga . The supracrustal rocks comprise nappe s that form part of the Ungava and Labrador Trough geology troughs . In the zone east of the Labrador Trough axis, the Paleoproterozoic deformation reworked the Archean rocks of the Douglas Harbour Domain, as well as the Paleoproterozoic diabase dykes. The metamorphic conditions which parallel the deformation increase from west to east and from middle amphibolite to granulite facies . uranium lead dating U Pb isotope analyses of zircon yield secondary ages around 1790 Ma. These results are interpreted as the age of metamorphism . They indicate reactivation of the northeastern margin of the Superior craton Superior Province during a Paleoproterozoic tectonic tectono Metamorphism metamorphic event, resulting from probable continent al collision. Madore, 2001 . See also Canadian Shield North American craton References Madore, L., and Y. Larbi. 2001 Regional structural character of the northeastern Ungava Peninsula Connection between the Rae and Superior provinces. St. John s 2001 Technical Programme SS2 Tectonic Integration of Circum Superior Orogens. Online Abstract http gac.esd.mun.ca gac 2001 seven sub program.asp?sess 98&form 10&abs no 118 Category Cratons Category Historical geology Category Geology of the Northwest Territories Category Geology of North America palaeo geo stub ...   more details



  1. Slave craton

    Craton From On Top The Crustal View. Geological Survey of Canada. http www.lithoprobe.ca Contributed ..., Wouter, Bill Davis, Herman gritter, and Alan G. Jones. 2004a The Slave Craton From Underneath The Mantle ...   more details



  1. Gawler craton

    siltstone . Subsequent deformation on the craton has been largely epeirogenic forming shallow fault ... and Spencer Gulf. Physiography The Gawler Craton, or Gawler Block, is a distinct physiographic province ... tectonic zone on the north western flank of the Gawler craton comprising dense, magnetic, highly ... of the craton. Eastern and Central, Gawler Ranges Palaeoproterozoic rocks of the eastern and central Gawler craton are overlain by relatively unmetamorphosed clastic s of the Corunna Conglomerate, the Gawler ..., the Gawler Range Volcanics, which extend from the centre of the craton to its eastern margin, represent ... of the craton as it is seen today. Central Yarlbrinda Shear Zone In the central Craton ... that have been found in the craton include gold , diamond s, copper , nickel , granite , iron ... of Prominent Hill located in the center of the craton. The 70 million tonne Kalkaroo Mine is to the south ... portion of the Kingoonya Palaeochannel system within the southern Gawler Craton. Warrior is the most significant known uranium occurrence in the Gawler Craton. Stellar, 2006 . See also Geology of Australia Australian Shield Western Plateau Pilbara craton Yilgarn craton Ore genesis References reflist ...   more details



  1. Zimbabwe craton

    File Southern African Cratons.svg thumb 300px Southern Africa showing location of Zimbabwe craton The Zimbabwe craton is an area in Southern Africa of ancient continental crust and an example of Early Archaean lithology dating back to 3.5 billion years ago Gigaannum Ga. in the southern Africa n nation of Zimbabwe ref Wilson, J.F., Nesbitt, R.W., Fanning, C.M., 1995. Zircon geochronology of Archaean felsic sequences in the Zimbabwe craton a revision of greenstone stratigraphy and a model for crustal growth. In Coward, M.P., Ries, A.C. Eds. , Early Precambrian processes, vol. 95. Geological Society ... Marginal Zone of the Kaapvaal craton to the Northern Marginal Zone of the Zimbabwe craton ca. 2.8 ... craton. Journal of African Earth Sciences , 34 , 157 166 ref . Granitoids of the same and greater age as the 3.46 Ga Tokwe granitoid gneisses in the south central portion of the Zimbabwe craton are recognised .... This crustal block, also known as the Sebakwe Proto craton, was fully stabilised by around 3.35 Ga ... N Noble, and James F. Wilson. 1999 The Sebakwe Proto Craton An Extensive Early Archaean Crustal Block in Zimbabwe A Reassessment of Craton Formation, Stabilisation and Growth. Journal of Conference ... predominance of these rocks, and occurred ca. 400 Ma after the initial stabilisation of the craton ... an arc accretion origin for the craton ref Blenkinsop, T.G., Martin, A., Jelsma, H.A., Vinyu, M.L., 1997. The Zimbabwe Craton. In de Wit, M.J., Ashwal, L.D. Eds. , Greenstone Belts. Oxford University ... . Ca. 2.5 Ga Wedza and Chilimanzi suites, south eastern Zimbabwe craton The final stage of the cratonization process of the Zimbabwe craton is marked by emplacement of large volumes of monzogranitic and granodioritc ... craton, between the Mutare Odzi greenstone belt and the Northern Marginal Zone of the Limpopo Belt ... and Andreas Schmidt. 1999 Crustal Evolution in the SE Zimbabwe Craton. http www.the conference.com ... craton Limpopo Belt References references Major African geological formations Category Cratons ...   more details



  1. Yilgarn Craton

    The Yilgarn Craton is a large craton which constitutes the bulk of the Western Australia n land mass ... dated as old as 4.4 Ga. TOCright Geology The Yilgarn Craton appears to have been assembled between ... by widespread granite and granodiorite intrusions, which comprise over 70 of the Yilgarn craton voluminous ... greenstone successions in the central Yilgarn Craton, Western Australia. Precambrian Research ... as the emplacement of the vast majority of the craton s endowment in gold mineralisation. These accretion ... fragments separated by pauses in subduction , with renewed activity occurring episodically. The craton ..., at 2.75 2.65 Ga. The craton is one of the distinct physiographic provinces of the Australian ... 2007 08 14 ref . The Western Gneiss Terrane is distinct from the remainder of the Yilgarn Craton ... is exposed along the western half of the northern margin of the Yilgarn Craton as the Narryer Gneiss ... edge of the Yilgarn Craton, partially covered by Phanerozoic sedimentary basins and in faulted ... Craton the Balingup Gneiss Complex is situated inboard from the Early Proterozoic Leeuwin ... substrate upon which the majority of the Yilgarn Craton s c. 2.70 to 2.55 Ga greenstone metavolcanic ... Province is exposed in the western and northern third of the Yilgarn Craton. The Province ... of the craton and the Western Gneiss Belt. The Murchison Province Stratigraphy, after Watkins 1990 ... framework in the northeastern Yilgarn craton was largely shaped by transpression that led to the development .... Southern Cross Province The Southern Cross Province lies in the central area of the Yilgarn craton ... of the Kalgoorlie Terrane, Yilgarn Craton, Western Australia. in, The Archaean Terrains, Processes ... in the Norseman Wiluna Belt, Yilgarn Craton, Western Australia. Precambrian Research, Vol ... Craton is bound on all sides by younger terranes of various ages, but predominantly of Proterozoic ... Archaean events which have involved the Yilgarn Craton. Perth Basin The Yilgarn Craton is bound on the western ...   more details



  1. Kaapvaal craton

    on the countries. The bold outline shows the parameters of the present day Kaapvaal craton. The Kaapvaal craton Limpopo province of South Africa , along with the Pilbara craton of Western ... records from both these craton s, especially of the overlying late Archean sequences, suggest that they were once part of the Vaalbara supercontinent Zegers et al. , 1998 . The Kaapvaal craton covers an area of approximately 1.2 million square kilometers and is joined to the Zimbabwe craton to the north by the Limpopo Belt . To the south and west, the Kaapvaal craton is flanked by Proterozoic orogeny ... rocks associated with the breakup of Gondwana . The Kaapvaal craton formed and stabilized between ... arc related magmatism and sedimentation cycle. The craton is a mixture of early Archean 3.0 3.5 Ga granite ... by a variety of granitic pluton s 3.3 3.0 Ga . Subsequent evolution of the Kaapvaal craton ... sequences were developed. Early Archean crust is well exposed only on the east side of the craton and comprises .... Late Archean metamorphism joined the Southern Marginal Zone of the Kaapvaal craton to the Northern Marginal Zone of the Zimbabwe craton ca. 2.8 2.5 Ga by the 250 km wide orogeny orogenic ... to early Paleoproterozoic succession on the craton were sourced from the 2.65 2.70 ... Ga detrital zircon s. This implies that the Limpopo Complex together with the Zimbabwe craton only became attached to the Kaapvaal craton at 2.0 Ga during formation of the Magondi Mobile Belt which ... in the eastern edge of Kaapvaal Craton. It is well known for its gold mineralisation and for its ... ca 3.2 3.1 Ga . The GMS suite are found over large parts of the Kaapvaal Craton and their emplacement coincides with the first stabilization of the central parts of the craton. The GMS suite in the Barberton ... was halted, perhaps by arrival of a micro craton. The 3.1 Ga Mpuluzi batholith in the Barberton ... Archaean Coppin Gap greenstone belt of Western Australia See Yilgarn craton . Similarities ...   more details



  1. John Craton

    John Douglas Craton is an American classical composer . His works, which have at times been compared favorably to those of Gustav Holst and Ralph Vaughan Williams , have been performed throughout the United States and Europe . While his compositions cover a diverse range, he is best known for his operas and works for classical mandolin . ref http www.operaamerica.org Content Archive Publications index.aspx Opera America, Fall 2007, pp. 46 47. ref Biography Craton was born August 6, 1953, in Anniston, Alabama . Though neither of his parents was musical, his extended family included many musicians, both amateurs and professionals, ref http www.mandolinmagazine.com A Classical Approach New Music ... State University before transferring to Lipscomb University , where he earned his B.A. Craton studied ... Fusner . His graduate degree from Indiana University was in audiology , and Craton practiced as a clinical ... Key by Joel Pierson, H&L, June 2010, volume 6, number 5, pp. 20 23. ref Craton s music is highly ... John Craton, Composer, by Carol Johnson, Bedford Times Mail, March 6, 2006. ref His music has been ... described Craton s music as coming from some other time and planet, stating that although he may be an American ... peace and joy. Many of Craton s works are published by Wolfhead Music . ref http www.tmnews.com ... 29, 2008. ref While in his early years Craton often performed on violin , piano , recorder , and other ... Biber Biber Sonata Representativa string orchestra Craton Lullaby from Four Whimsies string orchestra ... of John Craton . Ann Putnam Overture, Excerpts from The Parliament of Fowls, The Reconciliation ... 08. References references External links http www.craton.net John Craton s Official Website http ... music.shtml Contemporary Music for Mandolin http www.classicalguitar.nl craton john.aspx Classicalguitar ... Craton Operas at AllAboutOpera.com http wolfheadmusic.com comps.htm craton Wolfhead Music Composer Biography DEFAULTSORT Craton, John Category 1953 births Category Living people Category American composers ...   more details



  1. Pilbara craton

    The Pilbara craton the Pilbara province in northwest Western Australia , along with the Kaapvaal craton ... supercontinent , and then believed to have belonged to Ur continent Ur continent. The Pilbara Craton ... Tabba Shear zone Shear Zone is the major division between the East and West Pilbara craton . The Tabba ... Major Tectonic Cycle The Pilbara craton evolved over two approximately 360 annum Ma tectonic cycles ..., but a much greater degree of crustal reworking has occurred in the Pilbara Craton than is required ... and Recycling of Archaean Continental Crust in the Pilbara Craton. Journal of Conference Abstracts ... constraints on the timing of tectonic events in the Archaean Central Pilbara Craton, Western Australia ... archean craton in the north. Granite is exposed in the Hamersley basin as batholiths up to a 100 ... of true TTGs in the Pilbara Craton are restricted to the older 3.44 Ga rocks of the granitic ... for the early Pilbara craton evolution. The geochemical geological and geophysical characteristics ... Craton, Australia. thesis, Geosciences, University of Sydney. Online Abstract http setis.library.usyd.edu.au ... Belt, Pilbara Craton, Australia. Geosciences, University of Sydney. Online Abstract http ... year old greenstone successions in the Pilgangoora Belt, Pilbara Craton, Australia. Journal of Conference ... Group of the craton . Basaltic greenstones range in age from 3.5 to 2.7 Ga. The greenstone ... Dome a non diapiric dome in the Archaean Pilbara Craton, Western Australia. Precambrian Research, Vol ... North Star Basalt in the Marble Bar Greenstone Belt, Archaean Pilbara Craton, Western Australia. thesis ... Pilbara Craton, W. Australia. Journal of Conference Abstracts, Vol. 4, No. 1. Symposium A08, Early ... at different periods in the Mid Archean tectonic evolution of the eastern Pilbara Craton. These we ... of the Pilbara Craton is overlain by the Wyloo Group with a maximum thickness of 10  km. and maximum ... Complex, Pilbara Craton. Physiography The Pilbara craton or Pilbara block , is distinct physiographic ...   more details



  1. Dharwar craton

    The Dharwar craton in South India presents a natural cross section of late Archaean continental crust. There are three main structural zones a root zone of highly heterogeneous petrology from monzonite to granite and texture phenocryst accumulation , a channel zone where evidences of large scale magma ascent can be observed, and a zone of superficial intrusion s, consisting in independent wiktionary Homogeneous homogeneous intrusive bodies. In the root zone, Mantle geology mantle derived magma underwent Fractional crystallization geology fractional crystallisation which was followed by mingling between the residual liquids and melts generated by anatexis of the surrounding gneiss ic Basement rock basement . The term Dharwaar supergroup is now used as synonymous with metamorphosed Archaean sediments and including all the schistose series below the eparchaean unconformity . The Dharwarian rocks are mostly unfossiliferous. Lithology of the Dharwars The rocks of this age show extremely complex nature with clastic and chemically precipitated sediments, volcanic and plutonic rocks all of which show varying degrees of metamorphism. The majority of the rocks are often phyllite s, schist s and slate s. There are hornblende , Chlorite group chlorite , haematite , and magnetite schists, Feldspar felspathic schists quartzite s and highly altered volcanic rocks, like rhyolite s and andesite s turned into hornblende schists abundant and widespread granitic intrusions crystalline limestone s and marble s Serpentine serpentinous marbles steatite masses beds of jasper s and massive beds of Iron oxide iron and manganese oxide s. References Auvrey, Bernard, Mudlappa Jayananda, B Mahabaleswar, Herv Martin and Jean Fran ois Moyen. 1999 From the Roots to the Top of a Granitic Body The Closepet Granite of South India. Journal of Conference Abstracts, Vol. 4, No. 1, Symposium A08, Early Evolution of the Continental Crust. http www.the conference.com JConfAbs 4 140.html Category Cratons regional ...   more details



  1. Superior craton

    rocks of arc affinity dominate the oceanic margins of the Superior craton and indicate that there was widespread ... day Superior craton. However, during the amalgamation collisions, five discrete orogenies are recognized ... host a variety of orogenic gold deposits across the province. Percival, 2006 . The Superior craton has a lithosphere thickness of at least 250  km beneath the craton, and possibly as much as 350 ... Superior proto craton The planet s oldest continental Crust geology crust up to 3.7 Ga occurs ... interpreted as a continental nucleus or proto craton that was created? during assembly of the Superior ... dating U Pb geochronology mapping with SHRIMP results support a ca. 3.0 Ga Superior proto craton ... 2.8 Ga proto craton extend from Manitoba to Ungava with mainly Tonalite Trondhjemite Granodiorite ... sequence . Juvenile Volcano volcanic rocks 2.8 Ga may have been incorporated into the proto craton prior ... in the granite greenstone and metasedimentary belts of the southern part of the craton. The northeastern ... and crustally derived granitoid magmatism. A northern proto Superior craton had continental magmatic ... ages from the Superior, Slave craton Slave , Churchill craton Churchill and Nain Provinces, represent coincidental cooling within individual craton s carrying separate and distinct Accretion geology ...   more details



  1. Arequipa?Antofalla craton

    The Arequipa Antofalla craton or terrane is a basement unit underlying the central Andes in Argentine Northwest northwestern Argetina , western Bolivia , Norte Grande northern Chile and southern Peru . The Arequipa Antofalla craton colided and amalgamated with the Amazonian shield Amazonian craton about 1000 Ma ago during the Suns s orogeny . ref Staci L. Loewy, James N. Connelly and Ian W.D. Dalziel. 2003. An orphaned basement block The Arequipa Antofalla Basement of the central Andean margin of South America ref References reflist SouthAm stub geology stub Category Geology of Argentina Category Geology of Bolivia Category Geology of Chile Category Geology of Peru ...   more details



  1. East European craton

    The East European craton is the core of the Baltica proto Tectonic plate plate and consists of three crustal regions segments Fennoscandia to the northwest, Volgo Uralia to the east, and Sarmatian craton Sarmatia to the south. Fennoscandia includes the Baltic Shield also referred to as the Fennoscandian Shield and has a diversified accretion ary Archaean and Early Proterozoic Crust geology crust , while Sarmatia has an older Archaean crust. The Volgo Uralia region has a thick sedimentary cover, however deep drillings have revealed mostly Archaean crust. There are two shields in the East European Craton the Baltic Fennoscandian shield and the Ukrainian shield. The Ukrainian Shield and the Voronezh ... European craton and marks the Late Paleozoic orogenic collision of the East European craton with the Siberia continent Siberian craton s. The southern margin of the craton is where Sarmatia ... is known as the Trans European Suture Zone and separates the East European craton from the Phanerozoic orogen s of Western Europe . The northwestern margin of the craton is overlaid by the fold and thrust ... aspect of the East European craton is the extensive 3 km and more thick Riphean stage Riphean middle ... thickness fluctuations of the crustal layers. A shield in any craton is the area of exposed crystalline crust while the other part of the craton is the Platform geology platform where the crystalline ... the crustal segments of the East European craton comprise both the Baltic Shield and the Ukrainian shield, and the sedimentary platform basement. Early tectonics The East European craton has a very complex ... EEC EPSL 03.PDF Lithospheric structure, composition, and thermal regime of the East European Craton ... Craton , in Selley, R.C., Cocks, L.R. and Plimer, I.R. Eds Encyclopedia of Geology , Amsterdam London ... www.geo.uw.edu.pl PTMINSP 2005 018.pdf The East European Craton Some Aspects of the Proterozoic Evolution ... East European Craton Category Cratons Category Historical geology Category Economic geology ...   more details



  1. Sao Francisco craton

    signature of the Umburanas greenstone belt, northern S o Francisco craton, Brazil doi 10.1016 ... Geography of South America South American Plate DEFAULTSORT Sao Francisco craton Category Cratons ...   more details



  1. West African craton

    File West African Craton.svg thumb right 300px West Africa The West African craton is one of the five ... , the others being the Kalahari craton , Congo craton , Saharan Metacraton and Tanzania craton . These land ... continent. At one time, volcanic action around the rim of the craton may have contributed to a major ... abstract 30 9 839 title Mantle insulation beneath the West African craton during the Precambrian Cambrian ... Location and composition The craton appears to have formed when three Archean cratons fused Leo Man ... craton docked with the craton around 2,000 Ma. The roots of the combined craton extend to a depth ... 12 26 ref The West African craton stretches from the Little Atlas mountains of Morocco to the Gulf ... 03 15 ref The West African craton underlies the modern countries of Morocco , Algeria , Mauritania , Senegal ... craton is not shown . The Earth formed about 4.6 billion years ago. ref name USGS1997 cite web year ... to reconstruct the early wanderings of the West African craton, but around 1,100 million years ago ..., the Congo craton lay to the west of the Amazonia craton , and the West African craton ... continents Proto Laurasia , the Congo craton and Proto Gondwana . ref aut Torsvik, T.H. 2003 The Rodinia Jigsaw Puzzle , Science 300 , pp. 1379 1381. ref The West African craton may then have combined ... firstsnowball.pdf format PDF ref At the end of this period the edges of the West African craton became ... geology mantle heat that had built up below the craton, insulated by the lithosphere . The volcanic ... covered by ice sheets, forests, marshes or arid desert, the surface of the West African craton has ... South of the mountains, the West African craton is relatively flat, mostly desert or dry savanna apart ... of the West African craton is interrupted by the remains of weathered volcanoes that are younger than the craton itself. Overlaying the Man Shield , the Birimian sequence of metasediments and metavolcanics ... cgi content full 297 1 1 title The boundaries of the West African craton, with special reference ...   more details



  1. East Antarctic craton

    Image Positions of ancient continents, 550 million years ago.jpg thumb 250px East Antarctica with Australia top during the early Paleozoic The East Antarctic craton is an ancient craton that forms most of Antarctica . It was part of the Nena supercontinent Nena supercontinent 1.8 billion years ago. During the early Paleozoic Era East Antarctica joined the Gondwana supercontinent . During the Mesozoic breakup of Gondwanaland, East Antarctica separated from other major continental areas. During and following this breakup the tectonic terranes of West Antarctica were added to form the current continent of Antarctica. References http pangea.stanford.edu research crustal abst.txt Stanford University abstract Continents of the world Category Natural history of Antarctica Category Geography of Antarctica Category Cratons Category Prehistory of Antarctica EAntarctica geo stub Geology stub it Cratone dell Antartide Orientale ja pt Crat o da Ant rtida Oriental ...   more details



  1. North China craton

    The North China Craton is one of the smaller continent al craton s of the Earth . It covers a total area of around 1.7 million square kilometre s 655,500 square miles in the northeast of China , most of Korea and the southern part of Mongolia , and has a shape quite akin to a funnel , with a long east west axis in the western part and two shorter perpendicular axes in the eastern half. Geological history The North China Craton is composed of several major blocks that have been heavily tilted and Fold geology folded over time as a result of collisions with other continent al land masses. The main blocks comprise the Eastern Block , the Western Block and the Central Orogenic Belt . The Central Orogenic Belt runs from western Liaoning through Beijing Municipality of China municipality to western Henan and contains chiefly igneous rock s of Paleoproterozoic age. The Western Block extends west from this region through Shanxi , Shaanxi , Inner Mongolia and northern Gansu . This block is the oldest and most stable part of the Craton and contains some of the oldest and mineralogically most valuable rocks in Asia , especially in Inner Mongolia where huge deposits of coal and iron ore are found. The Eastern Block is unusual for a craton in that it is affected severely by crustal thinning that began in the Mesozoic and is known to have reduced the thickness of the crust from 200 kilometres to as little as 80 kilometres. In the Changbai Mountains and Shandong there has been extensive volcano volcanism in the Tertiary. The crustal thinning of the Eastern Block is believed to be due to high heat flow within the plates especially the Pacific Plate surrounding the North China Craton. Prior to the Triassic , the North China Craton was an independent continent surrounded by oceans. For most ... of Pangaea during the Triassic. Geography The Eastern Block of the North China Craton consists ... DEFAULTSORT North China Craton Category Historical continents Category Cratons Category Geography ...   more details



  1. Río de la Plata craton

    Image Cratons West Gondwana.svg thumb right Approximate location of Mesoproterozoic older than 1.3  Ga cratons in South America and Africa. Image Mapageologico uruguay.jpg thumb right Geology of Uruguay Geological chart of Uruguay , showing the R o de la Plata Craton in central position light brown . The R o de la Plata craton is one of the five craton s ancient nuclei of the South American continent . The other four cratons are Amazonian craton Amazonian , S o Francisco craton S o Francisco , Rio Apa craton R o Apa and Arequipa Antofalla craton Arequipa Antofalla . It outcrop crops out in southern Geology of Uruguay Uruguay and parts of Argentina . Crystalline rock s of the R o de la Plata Craton are dated between 2200 and 1700 million years ago, such as rocks in Uruguay which are dated at 1790 5  Year SI prefix multipliers Ma . ref Cite journal last Halls first H.C. last2 Campal first2 N. last3 Davis first3 D.W. last4 Bossi first4 J. year 2001 title Magnetic studies and U Pb geochronology of the Uruguayan dyke swarm, R o de la Plata craton, Uruguay Paleomagnetic and economic implications journal Journal of South American Earth Sciences ref Dike geology Dikes trending ENE in the same area are dated by argon argon dating at 1727 10  Ma. ref Cite journal doi 10.1016 S0301 9268 98 00087 4 last Teixeira first W. last2 Renne first2 P.R. last3 Bossi first3 J. last4 Campal first4 N. last5 D Agrella Filho first5 M.S. year 1999 title 40Ar 39Ar and Rb Sr geochronology of the Uruguayan dike swarm, R o de la Plata Craton and implications for Proterozoic intraplate activity in Western Gondwana journal Precambrian Research volume 93 pages 153 180 ref The craton has a size of about 20,000 square kilometres . References Cite journal last Rapela first C.W. last2 Pankhurst first2 R.J. last3 Casquet first3 C. last4 Fanning first4 C.M. authors Baldo, E.G. Gonz lez Casado, J.M. Galindo, C. & Dahlquist, J. year 2007 title The R o de la Plata craton and the assembly of SW Gon ...   more details




Articles 1 - 25 of 481          Next


Search   in  
Search for Craton in Tutorials
Search for Craton in Encyclopedia
Search for Craton in Videos
Search for Craton in Books
Search for Craton in Software
Search for Craton in DVDs
Search for Craton in Store


Advertisement




Craton in Encyclopedia
Craton top Craton

Home - Add TutorGig to Your Site - Disclaimer

©2011-2013 TutorGig.com. All Rights Reserved. Privacy Statement