| 浙江龙泉地区变质基性岩年代学、地球化学特征及构造意义 |
| |
| 引用本文： | 刘远栋,刘风龙,张建芳,李翔,徐磊,温旭斌,倪伟伟.浙江龙泉地区变质基性岩年代学、地球化学特征及构造意义[J].地质学报,2021,95(2):413-426. |
| |
| 作者姓名： | 刘远栋 刘风龙 张建芳 李翔 徐磊 温旭斌 倪伟伟 |
| |
| 作者单位： | 浙江省地质调查院,杭州,311203;浙江省工业环保设计研究院有限公司,杭州,311203 |
| |
| 基金项目： | 本文为浙江省基础性公益性战略性地质工作项目(编号\[省资\]2018007、\[省资\]2018006)、中国地质调查局项目(编号12120114043101)资助成果。 |
| |
| 摘 要： | 浙西南龙泉地区集中出露一套中深变质岩系,是华夏地块的重要组成部分,对其形成时代和成岩构造属性等问题历来存在争议。本文通过对龙泉变质岩中变质基性岩的地球化学研究,认为这些岩石的原岩成岩环境至少有两类:Ⅰ类岩石稀土配分曲线、微量元素蛛网图特征均显示与IAB的相似性,微量元素比值和图解判别均指示这套岩石形成于与俯冲有关的岛弧构造环境;Ⅱ类岩石稀土配分曲线和微量元素蛛网图均与OIB有相似性,微量元素比值和图解判别也指示这套岩石形成于与俯冲无关的OIB构造环境。多种不同构造属性的岩石共生,佐证了原龙泉岩群变质岩系为一形成于早古生代的俯冲增生杂岩。变质基性岩锆石U-Pb测年获得其峰期变质时间为404~402Ma。龙泉俯冲增生杂岩的厘定对重新认识丽水-余姚断裂带构造属性、区域构造格架的建立以及进一步分析华夏造山系物质组成与结构提供了新资料。
|
| 关 键 词： | 变质基性岩 地球化学 俯冲增生杂岩 早古生代 龙泉 |
| 收稿时间： | 2020/2/20 0:00:00 |
| 修稿时间： | 2020/4/27 0:00:00 |
Geochronological and geochemical characteristics of the metamorphic basic rocks and their tectonic implications in the Longquan area, Zhejiang Province |
| |
| LIU Yuandong,LIU Fenglong,ZHANG Jianfang,LI Xiang,XU Lei,WEN Xubin,NI Weiwei.Geochronological and geochemical characteristics of the metamorphic basic rocks and their tectonic implications in the Longquan area, Zhejiang Province[J].Acta Geologica Sinica,2021,95(2):413-426. |
| |
| Authors: | LIU Yuandong LIU Fenglong ZHANG Jianfang LI Xiang XU Lei WEN Xubin NI Weiwei |
| |
| Institution: | 1) Zhejiang Institute of Geological Survey, Hangzhou, 311203;2) Zhejiang Province Industrial EP Design & Research Institute Co. Ltd, Hangzhou, 311203 |
| |
| Abstract: | The formation age,diagenetic,and tectonic attributes of a set of medium-deep metamorphic rock series exposed in the Longquan area,southwestern Zhejiang Province,an important component of the Cathaysian massif,remains controversial.Based on petrogeochemical studies of the metabasites from the Longqun metamorphic rocks,the diagenetic tectonic environments of these rocks can be divided into at least two types.TypeⅠrocks have the same REE distribution curves and spider diagram of trace element with IAB.The trace element ratio and discrimination diagrams indicate that these rocks were formed in an island arc setting which was related to subduction.TypeⅡrocks have the same REE distribution curves and spider diagram of trace element with OIB.The trace element ratio and discrimination diagrams indicate that these rocks were formed in a within-plate tectonic environment which were not relevant to the subduction.The rocks symbiosis of different tectonic attributes proves that the original Longquan Group is a subduction accretion complex.The zircon U-Pb dating of metabasites yielded the peak metamorphic ages between 404~402 Ma.This provides new data for reevaluatingthe tectonic attributes of the Lishui-Yuyao fault zone,the establishment of the regional tectonic framework,and the further analysis of the material composition and structure of the Cathaysian orogenic system. |
| |
| Keywords: | metabasites geochemistry subduction- accretion complex Early Paleozoic Longquan |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ |
| 点击此处可从《地质学报》浏览原始摘要信息 |
| 点击此处可从《地质学报》下载免费的PDF全文 |
|
