豫西太山庙地区大西沟锡矿LA-MC-ICPMS锡石U-Pb年龄及地质意义  

LA-MC-ICPMS U-Pb Geochronology of Cassiterite from the Daxigou Tin Deposit in the Taishanmiao Area, Henan Province, and its Geological Significance

作　　者：何玉良[1,2] 李开文 杜保峰 王小娟[1] 李肖龙[1,2] 方怀宾[1] HE Yu-liang;LI Kai-wen;DU Bao-feng;WANG Xiao-juan;LI Xiao-long;Fang Huai-bin(Henan Institute of Geological Survey,Zhengzhou 450001,China;Henan Key Laboratory for Metal Mineral Ore-forming Geological Process and Utilization of Resource,Zhengzhou 450001,China)

机构地区：[1]河南省地质调查院,郑州450001 [2]河南省金属矿产成矿地质过程与资源利用重点实验室,郑州450001

出　　处：《矿物岩石地球化学通报》2020年第2期319-326,共8页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：河南省地质调查院青年科技创新基金项目(豫科创[2019]KC-06号);中国地质调查局整装勘查项目(DD20190159-23)。

摘　　要：为研究豫西太山庙岩体与产于其与熊耳群火山岩外接触带的大西沟锡矿之间的关系,利用LA-MC-ICPMS锡石U-Pb测年方法,对大西沟锡矿进行了年代学研究。结果获得的锡石207Pb/206Pb-238U/206Pb谐和年龄为(122.10±0.71)Ma (MSWD=1.8),该年龄与太山庙岩体的末期岩浆侵位年龄120 Ma相一致,成岩与成矿年龄的一致性表明大西沟锡矿的成矿作用可能主要受控于太山庙岩体的岩浆侵入作用。结合东沟钼矿的形成时代(117~114 Ma)和康达萤石矿的成矿年龄(123±9.1 Ma),认为太山庙岩体周边的成矿作用可能形成于统一的构造岩浆过程,其动力学背景为中国东部中生代120 Ma左右的大规模岩石圈减薄事件。In this paper, the LA-MC-ICPMS U-Pb dating of cassiterite from the Daxigou tin deposit, occurred in the contact zone between the Taishanmiao granitoids and volcanic rocks of the Xiong’er Group in the taishanmiao area in Henan Province, has been carried out in order to study the relationship between tin mineralization of the Daxigou deposit and the Taishanmiao granitoids. The results show that the 207Pb/206Pb-238U/206Pb concordia age of cassiterite samples, which is 122.10±0.71 Ma(MSWD=1.8), is consistent with the obtained age of 120 Ma for the latest magma emplacement of the Taishanmiao granitoids. The age consistency of the granitic diagenesis and tin mineralization indicates that the tin mineralization in the Daxigou deposit could be controlled by the latest granitic magma intrusion of the Taishanmiao granitoids. Combining with the mineralization age of the Donggou molybdenum deposit(117-114 Ma) and the Kangda fluorite deposit(123±9.1 Ma), it is believed that various kinds of mineralization occurred around the Taishanmiao granitoids could be formed in a unitive tectonic and magmatic process under the geologic dynamic background of the Mesozoic large-scale lithospheric thinning event around 120 Ma in the eastern China.

关 键 词：大西沟锡矿 锡石U-Pb年代学 太山庙 豫西 

分 类 号：P618.44[天文地球—矿床学]