初论堰塞湖溃坝沉积相特征  

Discussion on Characteristics of Sedimentary Facies of Dammed-lakes Outburst Deposits

作　　者：崔之久[1,2] 张梅[3] 崔鹏[4] 陈剑[5] 魏明建[6] 葛永刚[4] 陈艺鑫[1] 李川川[1] 

机构地区：[1]北京大学城市与环境学院,北京100871 [2]北京大学深圳研究生院,广东深圳518055 [3]北京师范大学环境演变与自然灾害教育部重点实验室,北京100875 [4]中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [5]中国地质大学(北京)工程技术学院,北京100083 [6]首都师范大学资源环境与旅游学院,北京100048

出　　处：《山地学报》2015年第2期129-140,共12页Mountain Research

基　　金：国家自然科学基金重点项目(41230743)~~

摘　　要：堰塞湖溃坝类型包括冰川、冰碛,火山和多种块体地貌（滑坡、崩塌、泥石流等）过程,而溃坝堆积相的种种特点以后者所造成的最具代表性。堆积体平面展布范围大（几平方公里~几十平方公里）,剖面规模也大（高几十米）,层次（层理）和结构全剖面均一,无超大的砾石;微观上有部分泥石流堆积特点,显示是高密度流,搬运介质是水。堆积体很少细砂和粘土物质。在平面上可划分出：扇顶（上游）、扇中（中游）、扇缘（下游）等微相。According to their dam modes of origin,dammed-lakes outburst deposits can be devided into glacierdammed-lakes and moraine-dammed-lakes,lava-dammed-lakes and mass movements（ landslide,collapse,debris flow）- dammed-lakes. Furthermore,characteristics of sedimentary facies which are caused by mass movements are most representative. Our preliminary research and reference to others＇ work on mass movements-dammed-lakes outburst deposits of several typical regions（ Xuelongnang,Yinchanggou,Tangjiashan and the source region of Minjiang） demonstrate that spreading areas of many accumulated body are enormous ranging from several square kilometers to dozens of square kilometers; section sizes are also massive with heights of dozens of meters; layers（ beddings） and structures in the whole profile are homogeneous without oversized gravels. Microscopically,certain features of accumulated body are similar to debris flow such as current of higher density with water as transporting media. Microfacies of accumulation body can be divided into fanhead（ upstream）,middle fan（ midstream） and fan fringe（ downstream）.

关 键 词：溃坝堆积 冰川-冰碛 火山堆积 块体运动堆积 混杂堆积 

分 类 号：P512.2[天文地球—地质学] P931