Petrological,Geochemical Characteristics and Geological Significance of the Caledonian Peraluminous Granites in Heihai Region,Eastern Kunlun
Shi Bin
Zhu Yunhai
Zhong Zengqiu
Jian Kunkun
Abstract：Caledonian peraluminous granites (420.5 to 424.0 Ma),is closely related with the development and evolution of the crust.In order to study their composition features and formation mechchanism,petrographical and geochemical investigations were carried out.It consist of biotite tonalite,biotite granodiorite,biotite granite,two-mica granite and muscovite granite in Heihai region.The rock types are of calc-alkali series and high-K calc-alkaline series (SiO2 =65.32%-75.87%,K2 O/Na2 O=0.47-1.52,δ=1.09-3.00),and be-long to peraluminous granites or strongly peraluminous granites (A/CNK=1.02 -1.31).REE display relatively LREE-enriched and HREE-depleted characteristics,with moderate Eu negative abnormality.LILE are of relatively selective enrichment and HFS elements are of relatively depletion.The melting materials of source are metagreywacke and metapelite.Based on regional geology,this paper suggests that Heihai peraluminous granites were formed by partial melting of the alumina-silica crust,which was caused by mantle un-derplating and extension of the southern subduction accretionary complex.
Keywords：eastern Kunlun orogenic beltHeihai regioncaledonianperaluminous granitepetrology
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：20( 35-54 )