| 琼北翁田铝质A型花岗岩的锆石U-Pb年代学、地球化学特征及其地质意义 |
| |
| 引用本文： | 吕昭英,陈沐龙,胡在龙,傅杨荣,魏昌欣,袁勤敏,常振宇,黄武轩.琼北翁田铝质A型花岗岩的锆石U-Pb年代学、地球化学特征及其地质意义[J].华南地质与矿产,2019,35(3):306-316. |
| |
| 作者姓名： | 吕昭英 陈沐龙 胡在龙 傅杨荣 魏昌欣 袁勤敏 常振宇 黄武轩 |
| |
| 作者单位： | 海南省地质调查院,海南海口,570206;海南省资源环境调查院,海南海口,570206 |
| |
| 基金项目： | 中国地调局地质调查项目;中国地调局地质调查项目 |
| |
| 摘 要： | 琼北地区花岗岩出露较少,多零星分布在翁田镇至大致坡镇一带。本次研究选取该区域的翁田岩体为研究对象,通过LA-ICP-MS锆石U-Pb定年,限定该岩体形成时代为245.1±2.4Ma,属于中三叠世。翁田岩体主要岩性为中粒斑状黑云母正长花岗岩,属于高钾钙碱性系列,具有高SiO2(74.57~76.15wt%)、高碱(Na2O+K2O=7.15~8.48wt%)、低MgO(0.19~0.31wt%)的特征,属于准铝质-过铝质花岗岩。岩石轻稀土富集,重稀土亏损,具强的负Eu异常,富集大离子亲石元素如Rb、Th、U、K等,明显亏损Nb、Ta,强烈亏损Ba、Ti、Sr、P,具高10^4Ga/Al、FeOt/MgO、K2O/Na2O比值和高(Zr+Nb+Ce+Y)含量,具有铝质A型花岗岩特征。结合区域资料,翁田铝质A型花岗岩的出现,表明海南岛在中三叠世处于伸展环境。
|
| 关 键 词： | 琼北 翁田岩体 中三叠世 铝质A型花岗岩 锆石U-PB年代学 地球化学 |
Zircon UPb Geochronology,Geochemistry of the Wengtian Aluminous A-type Granites,Northern Hainan Island and Its Geological Implications |
| |
| LYU Zhao-Ying,CHEN Mu-Long,HU Zai-Long,FU Yang-Rong,WEI Chang-Xin,YUAN Qin-Min,CHANG Zhen-Yu,HUANG Wu-Xuan.Zircon UPb Geochronology,Geochemistry of the Wengtian Aluminous A-type Granites,Northern Hainan Island and Its Geological Implications[J].Geology and Mineral Resources of South China,2019,35(3):306-316. |
| |
| Authors: | LYU Zhao-Ying CHEN Mu-Long HU Zai-Long FU Yang-Rong WEI Chang-Xin YUAN Qin-Min CHANG Zhen-Yu HUANG Wu-Xuan |
| |
| Institution: | (Hainan Geological Survey, Haikou 570206, Hainan, China;Hainan Resources Environment Survey Institute, Haikou 570206, Hainan, China) |
| |
| Abstract: | Granite is less exposed in the northern part of Hainan Province, and mostly scattered in the area from Wengtian Town to Dazhipo Town. The Wengtian granite in this area is selected as the research object. Through LA-ICP-MS zircon U-Pb dating, the formation age of the Wengtian intrusion is determined to be 245.1+2.4 Ma, belonging to the Middle Triassic. The main lithology of Wengtian intrusion is medium-grained porphyry biotite syenite granite, belonging to high-K calc-alkaline series, which is characterized by high SiO2 (74.57-76.15 wt%), high alkali(NaO+K2O=7.15-8.48 wt%) and low MgO(0.19-0.31 wt%) and belongs to quasi-aluminous to peraluminous granite. The rocks are enriched in light rare earth, depleted in heavy rare earth, with strong negative Eu anomaly, enriched in large ion lithophile elements such as Rb, Th, U, K, etc., and obviously depleted in Nb, Ta, Ba, Ti, Sr and P. The rocks are characterized by high 10^4 Ga/Al, FeOt/MgO,K2O/Na2O ratio and high (Zr+Nb+Ce+Y) content, and are characterized by aluminous A-type granite. Combined with regional geological characteristics, the occurrence of Wengtian aluminous A-type granite indicates that Hainan Island was in an extensional environment during the Middle Triassic. |
| |
| Keywords: | Northern Hainan Island Wengtian intrusion Middle Triassic aluminous A-type granite zircon U-Pb geochronology geochemistry |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ |
|
