摘要
柯岛群分布于长春-延吉构造带东部的开山屯—汪清地区,开山屯地区出露的柯岛群缺少化石依据,其时代归属依旧存疑。在柯岛群上部及下部分别采集代表性样品进行碎屑锆石U-Pb(LA-ICP-MS)测年,上部细碎屑岩锆石年龄介于252~2304Ma之间,下部粗碎屑岩锆石年龄介于260~713Ma之间,并分别形成2个相近的峰值年龄;前者2个峰值年龄分别为263±2Ma、460±4Ma;后者2个峰值年龄分别为266±3Ma、463±4Ma,反映沉积碎屑物主要来源于奥陶纪及二叠纪地质体;最年轻的锆石为252Ma,其余相对年轻的锆石年龄集中于晚二叠世早期。结合柯岛群沉积建造组合特征及区域对比,认为其形成时代应为早三叠世,是古亚洲洋闭合后,造山带快速隆升形成的山间类磨拉石沉积。
Kedao Group is distributed in Ka shantun-Wang qing area at th e east end of Ch an g chun-Yanji tectocropped Kedao Group in Kaishantun area lacks fossil basis, and hence its age assignment isstill in doubt. In this study, representativesamples were collected in the upper ad lower part of Kedao Group, and the detrital zircon U-Pb ducted. The ages of the upper fine detrital zircon are 252？ 2304Ma and those of the lower crude spectively forimng two similar peak ages. The former two peak ages are 263±2Ma and 460±4Ma whereas the latter two peak ages are 266±3Ma and 463±4Ma,suggesting that clastic sediments were mainly derived from the geological body of Ordovician and Permian. The youngest zircon is 252Ma in age while the rest ages relative to the youngest zircon ages are concenAccording to combinational sedimentary fornat ion asemblage characteristics of Kedao Group and regional correlation,it is conclud-ed that the age should be Early Triassic, and they are intermontane quasi-molasse sedimentary rocks due to the rapid uplift of the oro- genic belt after the closure of the Paleo-Asian Ocean.
作者
付俊彧
杨晓平
杨帆
汪岩
那福超
钟辉
于宏斌
孙巍
宋维民
FU Junyu;YANG Xiaopin;YANG Fan;WANG Yan;NA Fuchao;ZHONG Hui;YU Hongbin;SUN Wei;SONGWeimin(Shenyang Institute of Geology and Mineral Resources,Shenyang 110034,Liaoning,China;Jilin Institute of Regional Geology and Mineral Survey,Changchun 130012,Jilin,China)
出处
《地质通报》
CAS
CSCD
北大核心
2018年第6期1037-1049,共13页
Geological Bulletin of China
基金
中国地质调查局项目<国家地质数据库建设与整合(东北)>(编号:121201207000171401)
<东北基础地质综合调查与片区总结>(编号:1212011220435)和<古亚洲构造域东段构造格局
演化历史研究及250万构造图编制>(编号:DD20179402-01)
