滇西北澜沧江结合带的边界断裂和主要特征  

BOUNDARY FAULTS AND MAIN CHARACTERISTICS OF THE LANCANG RIVER SUTURE ZONE IN NORTHWEST YUNNAN

作　　者：王学武 李新仁 严城民[2] 周喜林 王长兵 张子军 朱琳 WANG Xue-wu;LI Xin-ren;YAN Cheng-min;ZHOU Xi-lin;WANG Chang-bing;ZHANG Zi-jun;ZHU Lin(No.209 Geological Team of Yunnan Nuclear Industry,Kunming 650031,China;Regional Geological Survey Team,Yunnan Bureau of Geology and Mineral Resources,Yuxi 653100,Yunnan Province,China)

机构地区：[1]云南省核工业209地质大队,云南昆明650032 [2]云南省地矿局区域地质矿产调查大队,云南玉溪653100

出　　处：《地质与资源》2018年第4期366-370,共5页Geology and Resources

基　　金：中央地质勘查基金项目"云南省维西县海尼地区铀矿普查"(2013531002);昆明市产业创新发展重大项目(2015-2G-01984);云南省高新技术产业发展项目(201704)

摘　　要：澜沧江结合带的东、西边界断裂分别为位于澜沧江西岸的吉岔断裂和位于碧罗雪山主峰的碧罗雪山断裂.澜沧江结合带由上古生界吉东龙组(P1j)、沙木组(P2sm)组成,形成于浅海陆棚-陆棚边缘盆地环境.其中,沙木组上段(P2sm2)的火山岩形成于岛弧环境.沿吉岔断裂出露的超镁铁-镁铁岩划分为2个部分:吉岔超镁铁-镁铁-斜长花岗岩具蛇绿岩特征,很可能属澜沧江洋壳的零星残片,在澜沧江洋消亡过程(早中三叠世?)中迁移定位;维登镁铁岩属阿拉斯加型,是兰坪-思茅中生代沉积盆地消亡过程(白垩纪)中沿吉岔断裂上侵的产物.The eastern and western boundary faults of Laneang River suture zone are respectively Jieha Fault located on the west bank of Laneang River and Biluo Xueshan Fault along the main peak of Bilou Mt. The suture zone, consisting of the Upper Paleozoie Jidonglong and Shamu formations, is formed in the neritie shelf-shelf marginal basin environment, among which the volcanic rocks of upper member, Shamu Formation （P2sm^2） are formed in island-are setting. The uhramafic-mafic rocks outcropped along Jieha Fault can be divided into two parts： One is Jieha ultramafie- mafic-plagiogranite with the characteristics of ophiolite, probably the fragmentary remnants of Laneangjiang oceanic crust, migrated and emplaeed with the extinction of Laneangjiang Ocean （Early-Middle Triassic？ ）; The other is Weideng mafic rocks, belonging to the Alaskan-type, intruding upward along the Jieha Fault during the subduetion of the Mesozoic Lanping-Simao sedimentary basin in Cretaceous period.

关 键 词：澜沧江结合带 碧罗雪山断裂 吉岔断裂 吉东龙组 沙木组 吉岔超镁铁-镁铁-斜长花岗岩 维登镁铁岩 滇西北 

分 类 号：P542.3[天文地球—构造地质学]