老挝巴莱地区混杂岩的发现及地质意义  

Discovery and Geological Significance of Mélange in Parklai District,Laos

作　　者：王婷 李雁龙[1] 聂飞[3] WANG Ting;LI Yan-long;NIE Fei(Panxi Geological Party,BGEEMRSP,Xichang,Sichuan615000;The 106th Geological Team,BGEEMRSP,Chengdu611130;Chengdu Center,CGS,Chengdu610081)

机构地区：[1]四川省地质矿产勘查开发局攀西地质队,四川西昌615000 [2]四川省地质矿产勘查开发局一〇六地质队,成都611300 [3]中国地质调查局成都地质调查中心,成都610081

出　　处：《四川地质学报》2021年第4期551-554,561,共5页Acta Geologica Sichuan

基　　金：中国地质调查局成都地质调查中心老挝1∶20万巴莱幅、孟根陶幅地质填图项目(编号:DD20160107-10)。

摘　　要：老挝西部沙耶武里巴莱地区位于墨江-黎府火山弧带上,与思茅-彭世洛中新生代盆地的相接,常被认为发育史密斯地层。经调查发现该区域系由以浅变质陆源细碎屑岩、硅泥质岩、基性-中酸性火山岩为主的基质和以浅变质粗-细碎屑岩、基性火山岩、碳酸盐岩等为主的构造岩块组成的混杂岩系。本文在野外地质观察、岩相学、古生物化石研究基础上,归纳和总结了混杂岩系的物质组成、时代,初步阐述了巴莱西班波混杂岩对难河-程逸洋演化的指示意义。结果表明,巴莱西波班混杂岩是一套半深海-滨浅海相浅变质混杂地层,具有水道碎屑流沉积、滑塌沉积和同变形沉积混杂特征;异地同沉积灰岩中的双壳、珊瑚化石和上覆地层接触关系表明混杂岩形成于晚三叠世时期。这一发现为进一步探讨难河-程逸缝合带的空间配置和重塑东南亚构造古特提斯演化历史提供重要依据。The Parklai District of Sayaboury in West Laos is located in the Mojiang-Loei volcanic arc zone and is connected with the Mesozoic-Cenozoic Simao-Phitsanulok basin.It is often considered to be a place where Smith stratum is developed.A set of mélange series consisting of epimetamorphic terrigenous fine clastic rock,siliceous argillaceous rock,basic-intermediate acid volcanic rock and carbonatite are developed in the this area.The study indicates that the mélange in the western Parklai District is an epimetamorphic bathyal-littoral facies strata characterized by mélange consisting of channel clastic flow deposit,sloughing deposit and syn-deformed deposit.Bivalves and coral fossils in allochthonous synsedimentary limestone and contact relation with overlying strata indicate that the mélange was formed during the Late Triassic which provides an important basis for further studying the space allocation of the Nan Uttaradit structure and reconstructing the evolution of the Tethys in Southeast Asia.

关 键 词：混杂岩 物质组成 生物化石 晚三叠世 老挝 

分 类 号：P581[天文地球—岩石学]