福建屏南牛洋晚石炭世片麻状花岗岩地球化学特征及其地质意义  

Geochemical Characteristics and Geological Significance of Late Carboniferous Gneiss Granite in Niuyang,Pingnan County,Fujian Province

作　　者：林云志[1] Lin Yunzhi(The northern gelolgical party of Fujian,Fuzhou,350001)

机构地区：[1]福建省闽北地质大队,福州350001

出　　处：《福建地质》2025年第1期1-12,共12页Geology of Fujian

基　　金：福建省自然资源厅项目“福建1∶5万屏南县、棠口幅区域地质调查”。

摘　　要：屏南牛洋花岗岩发育片麻状、眼球状构造,岩石地球化学特征表明,该侵入岩属于钙碱性岩系列的高钾过铝质酸性侵入岩;稀土元素配分模式呈往右倾斜的“海鸥型”曲线,说明轻稀土富集,轻、重稀土分馏程度高。利用LA-ICP-MS锆石U-Pb测年法,获得(314.0±2.1)Ma、(318.0±2.6)Ma的结晶年龄,将侵入岩时代划为晚石炭世。综合分析认为,该侵入岩显示沉积岩熔融形成的S型花岗岩特征,形成于碰撞挤压的构造背景下,为陆内造山作用的产物。The Niuyang granite in Pingnan develops gneissic and augen-shaped structures.The lithogeochemistry characteristics indicate that the intrusive rocks belong to the high potassium peraluminous acidic intrusive rocks of the calcium alkaline rock seriess.The REE distribution pattern shows a rightward inclined"seagull-shaped"curve,indicating enrichment of light rare earth elements,high fractionation degree of light and heavy rare earth elements.Using the LA-ICP-MS zircon U-Pb dating method,crystallization age values of(314.0±2.1)Ma and(318.0±2.6)Ma were obtained,and the age of the intrusive rock was classified as the Late Carboniferous.Comprehensive analysis suggests that the intrusive rock exhibits characteristics of S-type granite formed by the melting of sedimentary rocks,formed under the tectonic background of collision and compression,and is a product of intracontinental orogeny.

关 键 词：晚石炭世 岩石地球化学 S 型花岗岩 陆内造山 屏南牛洋 

分 类 号：P588.3[天文地球—岩石学]