Peraluminous rock - Wikipedia
网页Peraluminous rocks are igneous rocks that have a molecular proportion of aluminium oxide higher than the combination of sodium oxide, potassium oxide and calcium oxide. [1] This contrasts with peralkaline in which the alkalis are higher, metaluminous where aluminium oxide concentration is lower than the combination, but above the alkalis, and ...
Peraluminous I-type granites - ScienceDirect
网页2012年11月15日 · Almost half (49.3%) of the I-type granites for which bulk chemical compositions are available are peraluminous — those peraluminous granites are known to be I-type because of their close association in space and character with less felsic metaluminous I-type granites.
Different melting conditions and petrogenesis of peraluminous …
网页2019年7月15日 · Detailed study of these peraluminous granites, which are the products of crustal melting, will give insights into the melting process and petrogenesis of peraluminous magmas and will further constrain the regional geological evolution.
Structure, geochronology, and petrogenesis of Permian …
网页2022年9月1日 · Peraluminous granites, whose distinguishing feature is high alumina saturation index (ASI = molar Al 2 O 3 /(CaO + Na 2 O + K 2 O) > 1.0), widely occur within orogenic belts worldwide and provide essential clues for crustal rheological and thermal evolution (Sylvester, 1998).
The Origins of Strongly Peraluminous Granitoid Rocks
网页2019年7月15日 · Strongly peraluminous granites (SPAGs), with 1.20 < A/CNK < 1.30, are relatively rare rocks. They contain significant modal abundances of AFM minerals such as Bt-Ms-Crd-Grt-And-Toz-Tur-Spl-Crn of potentially magmatic, peritectic, restitic, and xenocrystic origin. Determining the origin of a SPAG depends to a large extent on establishing the ...
Peraluminous granite related to tin mineralization formed by …
网页2022年11月1日 · Relative to the metaluminous monzogranites, the peraluminous tin-bearing rocks exhibit more evolved geochemical compositions with higher Si and lower Ca, P, Mg, Fe, and Ti and stronger depletion in Eu, Ba, Sr, Zr, Hf, and rare earth elements.
Strongly Peraluminous Granites across the Archean–Proterozoic ...
网页2019年6月7日 · Peraluminous granites are those that include corundum in their CIPW norms (Shand, 1927). This translates into excess Al 2 O 3 in their bulk composition that cannot be accommodated in feldspar by coordinating with Ca, Na, and K.
过铝质岩 - 百度百科
网页过铝质岩（peraluminous），氧化铝过饱和的 岩石。. 过铝质为N (Al2O3)＞N (Na2O)+N (K2O)+N (CaO) (分子数),标准矿物中出现刚玉 (C),特征矿物是原生白云母、黑云母、刚玉、电气石、黄玉、石榴子石、红柱石、堇青石。. [1] 过铝质岩（peraluminous），氧化铝过饱和 …
Peraluminous A-type granites formed through synchronous …
网页2023年6月5日 · The Mesoproterozoic peraluminous A-type KG pluton formed through multistage synchronous mixing, fractionation, and mingling with coeval evolved alkaline ME magma pulses concomitant with partial assimilation of country rocks, at mid crustal depth (± 4.5 kbar or ~ 17 km).
General Classification of Igneous Rocks - Tulane University
网页If there is an excess of Alumina over that required to form feldspars, we say that the rock is peraluminous. This condition is expressed chemically on a molecular basis as: Al 2 O 3 > (CaO + Na 2 O + K 2 O)