西藏林周盆地中侏罗统却桑温泉组碎屑锆石U-Pb年代学及地质意义  

Detrital zircon U-Pb chronology and geological significance of the Middle Jurassic Quesang Hot Spring Formation in Linzhou Basin,Tibet

作　　者：周豫 杨文光[1] 朱利东[1] 密文天[2,3] 解龙[1] 钟摇 麦源君 张洪亮 李楠 ZHOU Yu;YANG Wenguang;ZHU Lidong;MI Wentian;XIE Long;ZHONG Yao;MAI Yuanjun;ZHANG Hongliang;LI Nan(Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;School of Mines,Inner Mongolia University of Technology,Hohhot 010051,China;Key Laboratory of Mineral Resources in Western China(Gansu Province),Lanzhou University,Lanzhou 730000,China;School of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学沉积地质研究院,四川成都610059 [2]内蒙古工业大学矿学院,内蒙古呼和浩特010051 [3]兰州大学甘肃省西部矿产资源重点实验室,甘肃兰州730000 [4]成都理工大学地球科学学院,四川成都610059

出　　处：《沉积与特提斯地质》2023年第4期747-758,共12页Sedimentary Geology and Tethyan Geology

基　　金：国家自然科学基金项目(41972118);冈底斯-喜马拉雅铜矿资源基地调查项目(DD20160015);兰州大学西部矿产资源重点实验室开放基金(MRWCGS-2019-01)。

摘　　要：林周盆地位于冈底斯板块中部,对其进行盆地分析将为理解冈底斯板块构造演化过程提供重要的沉积学证据。本文以林周盆地中侏罗统却桑温泉组为研究对象,开展岩石学和碎屑锆石U-Pb年代学研究,结果显示却桑温泉组岩屑石英砂岩最年轻碎屑锆石年龄为169Ma,存在620~540Ma,1220~1055Ma等年龄峰值,其中最年轻碎屑锆石年龄是对特提斯洋壳俯冲引发的岩浆事件的响应。碎屑锆石区域对比研究表明却桑温泉组物源主要来自冈底斯中部唐加-松多造山带,为特提斯洋向北俯冲、向南增生过程的沉积记录。The Linzhou Basin is located in the middle of the Gangdese Plate.Basin analysis of the Linzhou Basin will provide important sedimentological evidence for understanding the tectonic evolution process of the Gangdese Plate.This paper takes the Middle Jurassic Quesang Hot Spring Formation in the Linzhou Basin as the research object,and conducted petrology and detrital zircon U-Pb chronology.The results show that the youngest detrital zircon age of the lithic quartz sandstone of the Quesang Hot Spring Formation is 169 Ma,with age peaks such as 170-200 Ma,540-620 Ma,and 1055-1220 Ma.The youngest detrital zircon age is the response to a magmatic event triggered by the subduction of the Tethys oceanic crust.Regional comparative studies of detrital zircons show that the source of the Quesang Hot Spring Formation is mainly from the Tanga-Songduo orogenic belt in central Gangdese,which is a sedimentary record of the northward subduction and southward accretion of the Tethys Ocean.

关 键 词：林周盆地 中侏罗统 却桑温泉组 碎屑锆石 物源分析 

分 类 号：P597.3[天文地球—地球化学]