A-type granite

A-type granite is a particular category of the S-I-A-M or 'alphabet' system which classifies granitoids and granitic rock by their photoliths or source.[1][2] The 'A' stands for Anorogenic or Anhydrous, as these granites are characterized by low water content and a lack of orogenic or transitional tectonic fabric.[3] Other SIAM categories are S, I, and M types.[1]

Alphabet Classification System

In mid 1970's Chappell and White established 2 fundamentally distinctive types of granite: rocks with attributes that could be derived from metasedimentary rock, “S-type” granites and those whose attributes derived from metaigneous rock, “I-type” granites.[4]    The addition of the A-type granitoids was proposed by Loiselle and Wones in 1979 however this type was based on tectonic regime and geochemical characteristics.[4]  The later M-type granitoids were based on their mantle-sourced protoliths and of having particular chemical characteristics.[1]

Occurrence

The A-type granites dominantly form within continental intraplate rifting or uplifting or at regional post-orogeny uplift or collapse.[5] Their formation could be either anorogenic, meaning far from any orogeny, or after orogeny is completed.[5]

Geochemistry

Chemical characteristics of A-type granites include high silica, alkalis, zirconium, niobium, gallium, yttrium and cerium.[2][6] The ratio of gallium to aluminium is high, as is the ratio of iron to magnesium.[2] There are lower levels of calcium and strontium.[6] By using Ga/Al ratio, fractionated felsic I or S-type granites can overlap in apparent composition.[2] Enriched alkalis include sodium, potassium, rubidium and caesium.[2][6] Other depleted elements include barium, phosphorus, titanium and europium.[2]

Subtypes

Subtypes include A1, anorogenic, derived from ocean island basalt; and A2 post-orogenic, derived by crustal melting or crust and mantle mixing.[2]

Sources

The source could be dry granulite left over from the loss of wet magma during orogenies.[7]

References

  1. ^ a b c 1.     Winter, John D. (2014). Principles of igneous and metamorphic petrology (Second; Pearson new international ed.), p. 402. ISBN 9781292021539.
  2. ^ a b c d e f g Eby, G. Nelson (1990-12-01). "The A-type granitoids: A review of their occurrence and chemical characteristics and speculations on their petrogenesis". Lithos. Alkaline Igneous Rocks and Carbonatites. 26 (1): 115–134. doi:10.1016/0024-4937(90)90043-Z. ISSN 0024-4937.
  3. ^ Clemens, J. D., Holloway, John R., White, A. J.R. (1986), Origin of an A-type granite: Experimental Constraints, American Mineralogist, Volume 71, pages 317-324.
  4. ^ a b Chappell, B. W.; White, A. J. R. (August 2001). "Two contrasting granite types: 25 years later". Australian Journal of Earth Sciences. 48 (4): 489–499. Bibcode:2001AuJES..48..489C. doi:10.1046/j.1440-0952.2001.00882.x. ISSN 0812-0099.
  5. ^ a b Barbarin, Bernard (July–December 1990). "Granitoids: Main petrogenetic classifications in relation to origin and tectonic setting". Geological Journal. 25 (3–4): 227–238. doi:10.1002/gj.3350250306.
  6. ^ a b c Clarke, D. B. (1992) Granitoid Rocks, Chapman  & Hall, London.
  7. ^ Whalen, Joseph B.; Currie, Kenneth L.; Chappell, Bruce W. (April 1987). "A-type granites: geochemical characteristics, discrimination and petrogenesis". Contributions to Mineralogy and Petrology. 95 (4): 407–419. doi:10.1007/BF00402202.

Read other articles:

BlackBerry Storm 9500

BlackBerry Storm 9500PembuatResearch In Motion (RIM)JaringanQuad Band 850/900/1800/1900 MHzKetersediaan menurut negaraApril 2009Faktor bentukcandybarDimensi112,5 mm x 62,2 mm x 14 mmBerat155 gSistem OperasiBlackberry OS 5.0.0.419CPUQualcomm MSM 0706164965Kartu ExternalMicroSDBateraiLi-Ion 1400 mAh removable/rechargeable cryptographic lithium cellInputSureType portrait dan multisentuh, QWERTY landscape, QWERTY portraitLayarHigh Resolution 240 x 320 TFT LCD TransmitifKamera3.2 MPKonektivitasBlu...

 

 

Kampanye Utara Jiang Wei

Artikel ini sebatang kara, artinya tidak ada artikel lain yang memiliki pranala balik ke halaman ini.Bantulah menambah pranala ke artikel ini dari artikel yang berhubungan atau coba peralatan pencari pranala.Tag ini diberikan pada Maret 2009. Ekspedisi Utara Jiang WeiBagian dari Tiga KerajaanTanggal247 – 262LokasiTiongkokHasil Tidak dapat disimpulanPihak terlibat Cao Wei Shu HanTokoh dan pemimpin Guo HuaiCao ShuangDeng Ai Jiang Wei Ekspedisi Utara Jiang Wei adalah sembilan invasi yang dilan...

 

 

Tournoi de tennis de Suède

Ne doit pas être confondu avec Tournoi de tennis Nordic Light. Tournoi de tennis de Suède Généralités Sport Tennis Création 1948 1968 Autre(s) nom(s) Nordea Open Éditions 56 (2023) 55 (2023) Catégorie WTA 125 ATP 250 Périodicité Annuelle Lieu(x) Båstad Participants 28 joueurs ou 32 joueuses en simple 16 équipes en double Statut des participants Professionnel Surface Terre battue (ext.) Directeur Sofia Arvidsson Dotation 115 000 $ (2023) 562 815 € (2023) Site...

Usman dan Fodio

First Caliph of the Sokoto Caliphate Uthman ɗan Fodio عثمان بن فوديُShehuAmir al-Mu'minin1st Caliph of the Sokoto CaliphateReign1803–1817CoronationGudu, June 1803PredecessorPosition establishedSuccessorMuhammad BelloBorn15 December 1754Maratta, GobirDied20 April 1817(1817-04-20) (aged 62)SokotoBurialHubbare, Sokoto[1]WivesMaimunaAishaHawa'uHadizaIssue23 children, including:Muhammad BelloNana AsmauAbu Bakr AtikuHausa (Ajami)عُثْمَانْ طَࢽْ ࢻُودِی...

 

 

Gereja Katolik di Wilayah Samudra Hindia Britania

Bagian dari seriGereja Katolik menurut negara Afrika Afrika Selatan Afrika Tengah Aljazair Angola Benin Botswana Burkina Faso Burundi Chad Eritrea Eswatini Etiopia Gabon Gambia Ghana Guinea Guinea-Bissau Guinea Khatulistiwa Jibuti Kamerun Kenya Komoro Lesotho Liberia Libya Madagaskar Malawi Mali Maroko Mauritania Mauritius Mesir Mozambik Namibia Niger Nigeria Pantai Gading Republik Demokratik Kongo Republik Kongo Rwanda Sao Tome dan Principe Senegal Seychelles Sierra Leone Somalia Somaliland ...

 

 

Kiranmoy Nanda

Indian politician Kiranmoy NandaMP of Rajya Sabha for Uttar PradeshIn office3 April 2012 – 2 April 2018Succeeded byVijaypal Singh Tomar, BJPConstituencyUttar PradeshMinister for Fisheries, Aqua-culture, Harbours of West BengalIn office1991–2011Preceded byBhakti Bhushan MandalSucceeded byAbu HenaMLAIn office1977–2011Preceded byPrasanta Kumar SahooSucceeded byconstituency abolishedConstituencyMugberia Personal detailsBorn (1944-05-16) 16 May 1944 (age 79)Contai, Bengal Presi...

Meseta Central

Plateau in Central Iberia A landscape of the Meseta in May. The Meseta Central (lit. 'central tableland', sometimes referred to in English as Inner Plateau) is one of the basic geographical units of the Iberian Peninsula. It consists of a plateau covering a large part of the latter's interior. Developed during the 19th century, the concept of meseta central was handled by Heinrich Moritz Willkomm in lower case, and eventually Salvador Calderón y Arana [es] was reportedly ...

 

 

Халкидонское христианство

ХристианствоБиблия Ветхий Завет Новый Завет Евангелие Десять заповедей Нагорная проповедь Апокрифы Бог, Троица Бог Отец Иисус Христос Святой Дух История христианства Апостолы Хронология христианства Раннее христианство Гностическое христианство Вселенские соборы Н...

 

 

Loch Awe railway station

Railway station in Argyll and Bute, Scotland Loch AweScottish Gaelic: Loch Obha[1]An Oban to Glasgow train approaching Loch Awe stationGeneral informationLocationLoch Awe, Argyll and ButeScotlandCoordinates56°24′08″N 5°02′28″W / 56.4021°N 5.0412°W / 56.4021; -5.0412Grid referenceNN124274Managed byScotRailPlatforms1Other informationStation codeLHA[2]HistoryOriginal companyCallander and Oban RailwayPre-groupingCallander and Oban Railway operat...

Charlottesville, Virginia

Charlottesville redirects here. For other uses, see Charlottesville (disambiguation). Independent city in Virginia, United StatesCharlottesville, VirginiaIndependent cityCharlottesville Downtown Mall SealNicknames: C'ville, Hoo-VilleMotto: A great place to live for all of our citizens.Location in the Commonwealth of VirginiaCharlottesville, VirginiaShow map of VirginiaCharlottesville, VirginiaShow map of the United StatesCoordinates: 38°1′48″N 78°28′44″W / ...

 

 

George Howard (Governor of Maryland)

American politician (1789-1846) George Howard22nd Governor of MarylandIn officeJuly 11, 1831 – January 17, 1833Preceded byDaniel MartinSucceeded byJames Thomas Personal detailsBorn(1789-11-21)November 21, 1789Annapolis, MarylandDiedAugust 2, 1846(1846-08-02) (aged 56)Howard County, MarylandRelativesJohn Eager Howard (father)Peggy Chew Howard (mother) Prudence Gough Ridgely George Howard (November 21, 1789 – August 2, 1846) was the 22nd Governor of the State of Maryland i...

 

 

Gavin Simonds, 1st Viscount Simonds

British barrister and Viscount The Right HonourableThe Viscount SimondsPC1953 photograph of Simonds by Sir Cecil BeatonLord High Chancellor of Great BritainIn office30 October 1951 – 18 October 1954Prime MinisterWinston ChurchillPreceded byThe Viscount JowittSucceeded byThe Viscount Kilmuir Personal detailsBorn28 November 1881 (1881-11-28)Reading, BerkshireDied28 June 1971(1971-06-28) (aged 89)Westminster, LondonNationalityBritishPolitical partyConservativeAlma materNew C...

Carta de los seis

La carta de los seis (en rumano, Scrisoarea celor şase) es una carta abierta firmada por seis altos cargos del Partido Comunista Rumano para criticar las políticas desarrolladas por Nicolae Ceauşescu, presidente de Rumanía. Los firmantes eran seis altos cargos del PCR: Gheorghe Apostol, Alexandru Bârlădeanu, Silviu Brucan, Corneliu Mănescu, Constantin Pîrvulescu y Grigore Răceanu. Luego de que fuese publicada el 11 de marzo de 1989 en la radio internacional de la BBC y en Radio Europ...

 

 

Haywood County, Tennessee

County in Tennessee, United States County in TennesseeHaywood CountyCountyHaywood County CourthouseLocation within the U.S. state of TennesseeTennessee's location within the U.S.Coordinates: 35°35′N 89°17′W / 35.58°N 89.29°W / 35.58; -89.29Country United StatesState TennesseeFounded1823Named forJohn Haywood[1]SeatBrownsvilleLargest cityBrownsvilleGovernment • MayorDavid LivingstonArea • Total534 sq mi (1,380&#...

 

 

Livry-Gargan

Livry-GarganNegaraPrancisArondisemenLe RaincyAntarkomunebelum ada pada 2005 Livry-Gargan merupakan sebuah komune di pinggiran timurlaut Paris, Prancis. Terletak 15.6 km (9.7 mil) dari pusat kota Paris. Livry-Gargan kembar dengan kota: Haringey, Britania Raya Cerveteri, Italia Furstenfeldbruck, Jerman Almunecar, Spanyol Sejarah Tanggal 20 Mei 1869, sebagian teritori Livry-Gargan dipisahkan dan bergabung dengan bagian teritori Clichy-sous-Bois dan sebagian kecil teritori Gagny untuk memben...

CHL Humanitarian of the Year

CHL Humanitarian of the Year AwardSportIce hockeyAwarded forAnnually to the Canadian Hockey League player judged to have made the most notable contribution to his community in a humanitarian senseHistoryFirst award1993Most recentLuke Prokop The CHL Humanitarian of the Year Award is given out annually to the Canadian Hockey League player judged to have made the most notable contribution to his community in a humanitarian sense. It is chosen from the winners of the QMJHL Humanitarian of the Yea...

 

 

Moldau (Region)

Die historischen Regionen, aus denen Großrumänien zusammengesetzt war. Die Westmoldau (Moldova) ist dunkelorange gefärbt Die Moldau (rumänisch Moldova) ist eine historische Landschaft im Nordosten Rumäniens und grenzt im Osten an die Republik Moldau, die jedoch in etwa auf dem Gebiet der historischen Landschaft Bessarabien liegt. Um die in Rumänien gelegene Region Moldau von der Republik Moldau zu unterscheiden, wird sie manchmal auch als Westmoldau bezeichnet. Umgangssprachlich wird he...

 

 

Comtes du Saint-Empire

Comte du Saint-Empire Armoiries d'un comte du Saint-Empire. Titulature Comte impérial Création Xe siècle Transmission Héréditaire ou personnel Assis sur Comté ou Nom de famille Type Titre de la haute noblesse d'empire immédiate modifier  Armorial du Saint-Empire. Un comte du Saint-Empire ou bref comte d'Empire (en allemand : Reichsgraf, en latin : comes imperii) est un comte qui (ou dont les ancêtres) avaient été élevés à ce statut par l'empereur du Saint-Empire r...

Rye

Species of grain Not to be confused with ryegrass. For other uses, see Rye (disambiguation). Rye Scientific classification Kingdom: Plantae Clade: Tracheophytes Clade: Angiosperms Clade: Monocots Clade: Commelinids Order: Poales Family: Poaceae Subfamily: Pooideae Genus: Secale Species: S. cereale Binomial name Secale cerealeL. Synonyms Secale fragile M.Bieb. Rye (Secale cereale) is a grass grown extensively as a grain, a cover crop and a forage crop. It is grown principally in an area f...

 

 

芬妮·白蘭克-柯恩

芬妮·白兰克-柯恩Fanny Blankers-Koen1988年的芬妮·白蘭克-柯恩个人资料出生(1918-04-26)1918年4月26日 荷蘭Lage Vuursche（英语：Lage Vuursche）逝世2004年1月25日(2004歲—01—25)（85歲） 荷蘭霍夫多普身高1.75米（5英尺9英寸）体重63公斤（139磅）运动运动田径俱乐部阿姆斯特丹Sagitta（英语：Phanos）;阿姆斯特丹ADA 奖牌记录 代表  荷蘭 奥林匹克运动会 1948年英國倫敦 100公尺（英语：...