滇西澜沧岩群时代归属、物源、古地理位置分析及意义  

Analysis of age, provenance and paleogeographic location of Lancang Group in western Yunnan and its significance

作　　者：黄晓明 牟传龙 彭智敏[2] 丛峰[2] 方广丰[4] Huang Xiaoming;Mou Chuanlong;Peng Zhimin;Cong Feng;Fang Guangfeng(Chengdu University of Technology,Chengdu 610059;Chengdu Institute of Geology&Mineral Resources,China Geological Survey,Chengdu 610081;Key Laboratory of Sedimentary Basins and Petroleum Resources,Ministry of Natural Resources,Chengdu 610081;Research Center of Applied Geology,China Geological Survey,Chengdu 610036)

机构地区：[1]成都理工大学地球科学学院,成都610059 [2]中国地质调查局成都地质调查中心,成都610081 [3]自然资源部沉积盆地与油气资源重点实验室,成都610081 [4]中国地质调查局应用地质研究中心,成都610036

出　　处：《地质科学》2022年第4期1197-1239,共43页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：四川盆地地质结构与深层油气综合调查项目(编号:DD20211210);云南省1:5万文东等3幅区域地质调查项目(编号:DD20160016)资助。

摘　　要：为约束澜沧岩群时代、物源、古地理位置,本文进行碎屑锆石U-Pb年代学研究,并综合以往研究成果。澜沧岩群具统计意义最年轻组年龄为432±11 Ma、436±8.9 Ma、464±3.9 Ma、467±4.3 Ma、541±17 Ma、543±22 Ma、574±19 Ma,且D1643-2样品中有3颗泥盆纪锆石,为383 Ma、393 Ma、410 Ma。物源具亲冈瓦纳大陆和亲扬子大陆性质,碎屑锆石年龄谱峰值主要集中在两个阶段:泛非期(650~500 Ma)、晚格林威尔期(990~900 Ma),次级年龄组(2 500 Ma)。结果表明:澜沧岩群古地理位于冈瓦纳大陆北缘,腾冲—保山地块与思茅—印支地块之间,澜沧岩群时代为寒武—泥盆纪。古特提斯洋具继承性扩张。In order to restrict the age, provenance and paleogeographic location of Lancang Group. In this paper, the U-Pb chronology of detrital zircon of Lancang Group is studied, combined with previous research results. The age of the youngest group of Lancang Group is 432±11 Ma, 436±8.9 Ma, 464±3.9 Ma, 467±4.3 Ma, 541±17 Ma, 543±22 Ma and 574±19 Ma, and there are three Devonian zircons in D1643-2 sample, 383 Ma, 393 Ma and 410 Ma. Its provenance comes from Gondwana and Yangtze continent. The peak of detrital zircon age spectrum is mainly concentrated in two stages: Pan-African period(650~500 Ma), Late Greenville Period(990~900 Ma) and secondary age group(2 500 Ma). Paleogeography is located in the northern margin of Gondwana continent, between Tengchong Baoshan block and Simao Indosinian block. The age of Lancang rock group is Cambrian Devonian. The ancient Tethys Ocean has inherited expansion.

关 键 词：碎屑锆石 澜沧岩群 滇西 物源分析 

分 类 号：P531[天文地球—古生物学与地层学] P597[天文地球—地质学]