摘要
一、成因类型划分:1.宏观特征:包括第四纪堆积物展布的地貌特征、岩性特征和岩层结构特征。2.微观特征:包括重矿物分析、差热分析、石英砂颗粒表面结构电镜扫描和δO^(18)值的古气候研究以及各种年代测定等。二、地层层序:1.全新统:主要为河流冲积物,其次为洞穴堆积物和一些沼泽淤积物等。2.上更新统:主要为广泛分布于漓江两岸,组成一级阶地的冲积层和零散分布的类黄土堆积物。3.中更新统:晚期为洪积物,分布于尧山山麓。早期为冰积物.呈岗垅状蜿蜒展布,主要为紫红色泥砾。
Ⅰ .Genetic types.
1 .Macroscopic characteristics, including the distribution, lithology and structure of the Quaternary sediments.
2 .Microscopic characteristics, including those given by heavy mineral analysis and differential thermal analysis, surface structures of quartz sand grains by scanning electron microscope ( SEM ), paleoclimate study by δ18O analysis and different kinds of age determination, etc.
Ⅱ .Stratigraphical sequence.
1 .Holocene, consisting mainly of fluvial sediments, with minor cave deposits and swamp deposits.
2.Upper Pleistocene, consisting mainly of widespread alluvium that constitutes the 1st-order terrace along both banks of the Lijiang River, and sporadic loessial soil.
3.Middle Pleistocene, consisting of diluvium of the late stage and glacial deposits of the early stage. The former is distributed along the piedmont of the Yaoshan Mt., while the latter mainly composed of violet -red boulder-clay is distributed in the form of hillocks and mounts.
出处
《中国岩溶》
CAS
CSCD
北大核心
1989年第4期291-299,共9页
Carsologica Sinica
