A-type granites: geochemical characteristics, discrimination and petrogenesis

Whalen, J B; Currie, K. L.; Chappell, B. W.

doi:10.1007/bf00402202

Cited by 4,653 publications

(2,890 citation statements)

References 39 publications

Supporting

108

Mentioning

2,583

Contrasting

Unclassified

196

Order By: Relevance

“…Collins et al, 1982;Eby, 1992;Jiang et al, 2002;Whalen et al, 1987). The Tiantangshan quartz porphyries also show similar geochemical characteristics of A-type granites affinity.…”

Section: Origin Of the Intrusionsmentioning

confidence: 73%

See 1 more Smart Citation

Petrogenesis of the Early Cretaceous Tiantangshan A‐type Granite in northwestern Guangdong province, SE China and tectonic implications

Jia

Wang

Geng

et al. 2017

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

“…Collins et al, 1982;Eby, 1992;Jiang et al, 2002;Whalen et al, 1987). The Tiantangshan quartz porphyries also show similar geochemical characteristics of A-type granites affinity.…”

Section: Origin Of the Intrusionsmentioning

confidence: 73%

“…Turner et al 1992), or partial melting of specific crustal sources (e.g. Whalen et al 1987). The Early Cretaceous Tiantangshan A-type granites have Nd isotopic compositions that are distinct from the Early Cretaceous mafic rocks.…”

Section: Origin Of the Intrusionsmentioning

confidence: 99%

Petrogenesis of the Early Cretaceous Tiantangshan A‐type Granite in northwestern Guangdong province, SE China and tectonic implications

Jia

Wang

Geng

et al. 2017

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

“…A-type granites are commonly found in within-plate anorogenic settings or in the final stages of an orogenic event (e.g. Collins et al 1982, Clemens et al 1986, Whalen et al 1987, Eby 1990, 1992, Dall'Agnol et al 1994. The melting of the lower crust associated to mantle plume action or extensional thinning of the lithosphere associated with stress release-stages and generation of faults or mega-fractures are some of the tectonic models for A-type granites production (e.g.…”

Section: Discussionmentioning

confidence: 99%

“…Collins et al 1982, Clemens et al 1986, Whalen et al 1987, Eby 1990, 1992. On the Zr+Nb+Ce+Y versus 10 4 Ga/Al diagram, the samples plot in the A-type granites field (Fig.…”

Section: Petrographymentioning

confidence: 97%

K'Mudku A-type magmatism in the southernmost Guyana Shield, central-north Amazon Craton (Brazil): the case of Pedra do Gavião syenogranite

Souza

Dantas

et al. 2015

Braz. J. Geol.

View full text Add to dashboard Cite

<p>The Mesoproterozoic K'Mudku event (1490 - 1147 Ma) is represented by a britlle-ductile shear belt that cuts across the Paleoproterozoic units in the southernmost Guyana shield, central-north Amazon craton. This event produced mylonitization and cataclasites at low/medium- to high-grade metamorphic, and local within-plate magmatism. In the Amazonas State, Brazil, A-type magmatism chronologically associated to K'Mudku has been reported for the Pedra do Gavião and Samaúma syenogranites. However, the spatial relationship between K´Mudku event and A-type magma generation are not yet adequately clarified in the region. The Pedra do Gavião syenogranite is a high-K alkaline, metaluminous, reduced A-type granite with a post-collisional to within-plate geochemical signature. It has U-Pb zircons crystallization age of 1218 Ma and inherited zircons with ages between 1820 and 1720 Ma, which, together with the Sm-Nd data, suggest melting of Paleoproterozoic basement rocks of the Cauaburi Complex (1810 - 1780 Ma) regional unit. These data demonstrate that the effects of the A-type magmatism associated to the end of the Grenvillian-Sunsas orogeny, reported primarily in the southwestern margin of the Amazon craton, may also be extended for the central-northern part of the Amazon craton. Probably the generation or emplacement mechanisms of A-type magma occurred with some degree of involvement in the final stages of the K´Mudku event. However, this tectonic framework conception still needs more geological and geophysical investigations. Therefore, these news data should instigate to the return of geological research in the region, as well as to debate on the tectonic evolution and A-type granites production during the Ectasian-Stenian period in the central-north Amazon craton.</p>

show abstract

“…High contents of Zr, Nb, Y, Ga and Rb and low contents of Ba and Sr for rocks of both groups (cf. Leitzke et al 2015) are characteristic of acid magmatism with alkaline affinity (Pearce et al 1984, Whalen et al 1987, Nardi 1991.…”

Section: Whole-rock Geochemistrymentioning

confidence: 99%

Zircon U-Pb geochronology, Sm-Nd and Pb-Pb isotope systematics of Ediacaran post-collisional high-silica Acampamento Velho volcanism at the Tupanci area, NW of the Sul-Rio-Grandense Shield, Brazil

et al. 2017

View full text Add to dashboard Cite

ABSTRACT:We present new U-Pb zircon ages and Sm-Nd-Pb isotopic data for volcanic and hypabyssal acid rocks from the northernmost exposure of the Acampamento Velho Formation in the NW portion of the Sul-Rio-Grandense Shield, Brazil. The first volcanic episode, grouped in the high-Ti rhyolites from the Tupanci hill, shows age of 579 ± 5.6 Ma, which is in agreement with the post-collisional Acampamento Velho Formation volcanism in the Bom Jardim Group of the Camaquã Basin. A poorly constrained age of 558 +/-39 Ma was obtained for rhyolites from the low-Ti group at the Picados Hill, which may indicate a younger acid volcanism, or a greater time span for the volcanism of the Acampamento Velho Formation in southernmost Brazil. Regarding magmatic sources, Sm/Nd isotopic data coupled to Pb isotopes and a review of trace element geochemistry indicate different amounts of Paleoproterozoic (Dom Feliciano, Pinheiro Machado Suite) to Neoproterozoic (Rio Vacacaí terrane) lower crust melting. Our data, coupled with literature data, contribute to a better understanding of the stratigraphic evolution for the Neoproterozoic post-collisional volcanic successions of the Camaquã Basin in the Sul-Rio-Grandense Shield. KEYWORDS:Volcanism; Acampamento Velho Formation; Camaquã Basin; Tupanci; Geochronology. RESUMO: Novas idades obtidas por meio do método U-Pb em zircão e dados isotópicos Sm-Nd-Pb são apresentados para as rochas vulcânicas e hipabssais ácidas da exposição mais setentrional da Formação Acampamento

show abstract

A-type granites: geochemical characteristics, discrimination and petrogenesis

Cited by 4,653 publications

References 39 publications

Petrogenesis of the Early Cretaceous Tiantangshan A‐type Granite in northwestern Guangdong province, SE China and tectonic implications

Petrogenesis of the Early Cretaceous Tiantangshan A‐type Granite in northwestern Guangdong province, SE China and tectonic implications

K'Mudku A-type magmatism in the southernmost Guyana Shield, central-north Amazon Craton (Brazil): the case of Pedra do Gavião syenogranite

Zircon U-Pb geochronology, Sm-Nd and Pb-Pb isotope systematics of Ediacaran post-collisional high-silica Acampamento Velho volcanism at the Tupanci area, NW of the Sul-Rio-Grandense Shield, Brazil

Contact Info

Product

Resources

About