广西花山-姑婆山燕山期花岗岩的地球化学特征及成因研究  

Geochemistry and petrogenesis of the Yanshanian Huashan-Guposhan granites in Guangxi

作　　者：顾晟彦[1] 华仁民[1] 戚华文[1,2] 

机构地区：[1]内生金属矿床成矿机制研究国家重点实验室南京大学地球科学系 [2]中国科学院地球化学研究所,贵州贵阳550002

出　　处：《岩石矿物学杂志》2006年第2期97-109,共13页Acta Petrologica et Mineralogica

基　　金：国家重点基础研究发展规划研究项目(1999CB403209)国家自然科学基金重点资助项目(40132010)

摘　　要：广西花山-姑婆山燕山期花岗岩体以高硅、高钾、富碱、低磷、准铝质为特征,具有较高的 TFeO/MgO 值,富集大离子亲石元素、高场强元素和稀土元素,普遍出现褐帘石,应归属于富钾的钙碱性花岗岩(KCG)系列岩石,相当于高钾钙碱性Ⅰ型花岗岩。产生于后造山陆内挤压向拉张转换的地球动力学背景下,其形成与岩石圈伸展-减薄、亏损地幔岩浆的上涌和富含金云母-钾质碱镁闪石的岩石圈地幔的部分熔融有关。The Yanshanian Huashan-Guposhan granites in Guangxi are characterized by high silicon, high potassium, high alkaline, low phosphor and metaluminous nature, with relatively high FeO^T/MgO ratios and enrichment of LILE, HFSE and REE. In addition, they commonly contain allanites. They can thus be assigned to the high-potassium calc-alkaline granite （or KCG in the classification system of Barbarin, 1999）. They were formed during the conversion of the tectonic setting from compression to extension. The extension-thinning of lithosphere, the upwelling of the depleted mantle, and the partial melting of the lithospheric mantle rich in phlogopite and K-richterite might have served as the principal factors in producing this kind of granitic rocks.

关 键 词：燕山期花山-姑婆山花岗岩体 KCG 含金云母-钾质碱镁闪石的岩石圈地幔 后造山 

分 类 号：P588.121[天文地球—岩石学] P581[天文地球—地质学]