首页 | 本学科首页   官方微博 | 高级检索  
     检索      

柴达木盆地北缘乌兰县牦牛山组碎屑锆石U-Pb定年及其地质意义
引用本文:冯乔,秦宇,付锁堂,柳益群,周鼎武,马达德,王立群,任军虎,王晨瑜.柴达木盆地北缘乌兰县牦牛山组碎屑锆石U-Pb定年及其地质意义[J].沉积学报,2015,33(3):486-499.
作者姓名:冯乔  秦宇  付锁堂  柳益群  周鼎武  马达德  王立群  任军虎  王晨瑜
作者单位:1.山东科技大学地球科学与工程学院 山东青岛 266590;
摘    要:应用LA-ICP-MS单颗粒锆石U-Pb定年方法, 对柴达木盆地北缘乌兰县上泥盆统牦牛山组两组砂岩样品开展了碎屑锆石U-Pb年代学研究。测年结果显示年龄值分布较宽, 可以划分为5个峰值年龄区间。在这些碎屑锆石中, 最小的年龄为407.9 Ma, 属于岩浆成因, 限定了该套地层的沉积下限, 为不早于早泥盆世末期, 结合区域地质与古生物资料, 该套地层为晚泥盆世。碎屑锆石的年龄分布表明本区可能存在五期区域性地质构造事件, 其中早古生代最为突出, 其次为新元古代和古元古代早期-新太古代晚期, 暗示这三期岩浆活动和变质作用较为活跃, 并为本套地层提供了主要的锆石来源, 具有多时代混合物源特征。样品中少量太古代碎屑锆石的谐和度较好, 为研究区附近可能存在太古宙古老地层提供了一定证据, 但仍需进一步研究。

关 键 词:碎屑锆石    U-Pb定年    构造件事    晚泥盆世    牦牛山组    柴达木盆地北缘
收稿时间:2014-05-20

U-Pb Age of Detrital Zircons and Its Geological Significance from Maoniushan Formation in the Wulan County,Northern Margin of Qaidam Basin
Institution:1.College of Geological Science and Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590;2.Geology Department/State Key Laboratory of Continental Dynamics, Northwest University, Xi'an 710069;3.Qinghai Oilfield Branch PetroChina, Dunhuang, Dunhuang, Gansu 736202
Abstract:This paper studied the age distribution of detrital zircons of sandstone in Maoniushan Formation of Upper Devoion of Wulan country from northern margin of Qaidam Basin using LA-ICP-MS U-Pb isotopic age of zircons. The results show that the detrital zircons of sandstone has a wide range of zircon age, which can be divided into 5 peak interval. This sequence of the strata possibly was deposited in the Late Devonian and not earlier than the end of Early Devonian according to the regional geological correlation and paleontological data. The age distribution of detrital zircons indicate that there may be events of five regional geological structure in this area, and the most prominent is the Early Paleozoic, followed by Neoproterozoic and Early Paleoproterozoic-Late New Archean, which imply that the three periods of metamorphism and magmatic activity is relatively active and provide the main source of zircon for this strata with a mixture of multi-source characteristics. The obtained age data indicate the multi-provenance of the sandstone. In addition, there are less Archean detrital zircon having a high degree of harmony, which has provided some basis for the possible existence of Archean old strata, but needs further research.
Keywords:detrital zircons  U-Pb dating  tectonic events  Late Devonian  Maoniushan Formation  northern margin of Qaidam Basin
本文献已被 CNKI 万方数据 等数据库收录!
点击此处可从《沉积学报》浏览原始摘要信息
点击此处可从《沉积学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号