黔南独山下泥盆统丹林组碎屑锆石特征及其地质意义  

Characteristics and Geological Significance of Detrital Zircons from the Lower Devonian Danlin Formation in Dushan County,Southern Guizhou Province

作　　者：韩雪 刘凌云 唐佐其 陈仁 唐婷婷 王琦 HAN Xue;LIU Lingyun;TANG Zuoqi;CHEN Ren;TANG Tingting;WANG Qi(Guizhou Geological Survey,Guiyang,Guizhou 550081;Department of Geoscience,Graduate School of Science,Osaka City University,Osaka,Japan 5588585)

机构地区：[1]贵州省地质调查院,贵州贵阳550081 [2]大阪市立大学理学研究科生物地球系专攻,日本大阪5588585

出　　处：《地质与勘探》2022年第2期352-359,共8页Geology and Exploration

基　　金：中国地质调查局项目(编号:DD20190370-34);贵州省科技支撑计划项目(编号:黔科合支撑[2020]4Y034号);贵州省地质矿产勘查开发局项目(编号:黔地矿科合[2017]29号、黔地矿科合[2018]29号)联合资助

摘　　要：黔南独山县位于江南造山带西南段古生代陆源盆地区,是研究盆地物质来源的良好场所。利用碎屑锆石年代学定量分析下泥盆统丹林组底部碎屑锆石年代学特征,可反映其物质来源;利用锆石较稳定特征定量分析锆石微量元素所代表的地质意义也具有可操作性。结果表明,根据丹林组碎屑锆石年龄分布特征,可将其分为4组:早古生代(427~560 Ma)、新元古代(600~995 Ma)、中元古代(1000~1600 Ma)、及前中元古代(>1600 Ma)。新元古代及其更老锆石源自附近江南造山带,而古生代锆石来自更遥远的华夏造山带;华夏板块西缘与扬子板块聚合俯冲作用相关的岩浆活动至少可以分为三个阶段:寒武纪早期、寒武纪中晚期,以及早志留纪;以丹林组为代表的下泥盆统可能形成于板块俯冲-碰撞相关事件之后的前陆盆地环境。Dushan County is located in the Paleozoic terrigenous basin in the southwestern part of the Jiangnan orogen,and is ideal to study the basin material source.The chronological characteristics of detrital zircons from the Lower Devonian Danlin Formation can be used to trace their material sources.It is also feasible to use stable characteristics of zircons to quantitatively analyze the geological significance recorded by zircon trace elements.The zircon age pattern,morphology,and trace element characteristics suggest that the detrital zircons of the Danlin Formation can be divided into four groups:Early Paleozoic(427~560 Ma),Neoproterozoic(600~995 Ma),Mesoproterozoic(1000~1600Ma),and Pre-Mesoproterozoic(>1600 Ma).Neoproterozoic and older zircons are inferred to be derived from the nearby Jiangnan orogeny.The Paleozoic zircons are inferred to be originated from the more distant Cathaysia orogeny.The magmatic activity related to the aggregation and subduction of the Yangtze Plate and the northern margin of the Cathaysia Plate can be divided into at least three stages:Early Cambrian,middle and late Cambrian,and Early Silurian.The Lower Devonian represented by the Danlin Formation may be formed in a foreland basin environment after the subduction-collision related events on the northern margin of the Cathaysia Plate.

关 键 词：下泥盆统 丹林组 碎屑锆石年龄 岩浆活动 前陆盆地 独山县 黔南 

分 类 号：P534.44[天文地球—古生物学与地层学] P588.21[天文地球—地质学]