北秦岭蟒岭花岗岩体岩浆演化及源区:来自矿物学和Sr-Nd-Hf同位素证据  

Magmatic Evolution and Origin of Mangling Granitic Pluton in North Qinling,China:Evidence from Mineralogy and Sr-Nd-Hf Isotopes

作　　者：杨阳[1] 柯昌辉[2] 王晓霞[2] 李金宝[1] 吕星球 聂政融 YANG Yang;KE Chang-hui;WANG Xiao-xia;LI Jin-bao;LYU Xing-qiu;NIE Zheng-rong(School of Earth Science and Resources,Chang'an University,Xi'an 710054,Shaanxi,China;MNR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;No.214 Geological Party,Hunan Geological&Mining Organization for Non-ferrous Metals,Zhuzhou 412007,Hunan,China;Henan New Road&Bridge Group Motorway Management Co.,Ltd.,Zhengzhou 450018,Henan,China)

机构地区：[1]长安大学地球科学与资源学院,陕西西安710054 [2]中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室,北京100037 [3]湖南省有色地质勘查局二一四队,湖南株洲412007 [4]河南新路桥集团高速公路管理有限公司,河南郑州450018

出　　处：《地球科学与环境学报》2022年第4期658-674,共17页Journal of Earth Sciences and Environment

基　　金：中国地质调查局地质调查项目(1212010012012);国家自然科学基金项目(41972094,42172065)。

摘　　要：蟒岭花岗岩体位于北秦岭构造带黑沟—栾川断裂和乔端—瓦穴子断裂之间,是由3期岩浆侵入形成的岩浆杂岩体,其岩石类型从早到晚依次为含辉石黑云母闪长岩、二长花岗岩和黑云母正长花岗岩。在详细的野外调查和岩相学观察基础上,对蟒岭花岗岩体中的前两期岩石进行了系统的矿物学和Sr-Nd-Hf同位素研究。结果表明:蟒岭花岗岩体以I型花岗岩为主,从早到晚(含辉石黑云母闪长岩→二长花岗岩→黑云母正长花岗岩),其岩石成因类型具有从I型向I-A过渡型花岗岩变化的趋势;含辉石黑云母闪长岩和二长花岗岩中黑云母形成于较高氧逸度环境,其结晶温度分别为675℃~740℃和550℃~675℃;蟒岭花岗岩体是古老地壳物质部分熔融形成的长英质岩浆与可能起源于幔源的基性岩浆混合而成的产物。Mangling granitic pluton is located between Heigou-Luanchuan fault and Qiaoduan-Waxuezi fault in North Qinling.It is a magmatic complex formed by 3 stages of magmatic intrusion,including pyroxene-bearing biotite diorites,monzogranites and biotite syenogranite from early stage to late stage.Based on detailed field survey and petrographic observation,the mineralogy and Sr-Nd-Hf isotopes of the first two rocks in Mangling granitic pluton were systematically studied.The results show that Mangling granite pluton is mainly I type granite;from early stage to late stage(pyroxene-bearing biotite diorites→monzogranites→biotite syenogranites),the petrogenetic type of granite has a tendency of changing from I type to I-A transitional type;the biotites from the first two rocks are formed in high oxygen fugacity,and their crystallization temperatures are 675℃-740℃and 550℃-675℃,respectively;Mangling granite pluton is a mixture of felsic magma formed by partial melting of ancient crust and mafic magma possibly derived from mantle.

关 键 词：花岗岩 矿物学 黑云母 SR-ND-HF同位素 岩浆演化 源区 北秦岭 

分 类 号：P597[天文地球—地球化学] P57[天文地球—地质学]