陕晋蒙三角地带能源基地风沙沙源物质的初步研究

本文从堆积风沙物质的空间条件、风沙物质的类型及分布、风沙物质的演变及其区域分异规律四个方面论述区内土地沙漠化的物质基础。区内现代地貌及其营力特征表现为风与流水的交替作用。主要的风沙沙源物质为基岩风蚀和基岩风化壳的分选搬运;河湖相松散堆积物;河流阶地堆积物以及古风沙、风尘堆积物。初步将沙黄土分为粉沙质沙黄土和细沙质沙黄土。风沙物质的演变具有多旋回性、继承性、改造性以及演变因素的复杂性。自Q_2以来至少经历了14个风沙活动旋回。风沙物质的空间分布具有扩散性和交错分布的模式及镶嵌环带结构,即库布齐和毛乌素沙地两个核心,围绕这两个核心的是细沙质沙黄土环带。

A PRELIMINARY STDY ON THE SOURCE-SEDIMENT OF SHIFTING SAND IN THR TRI-BOUNDARY REGION AMONG SHAANXI PROV., SHANXI PROV., AND INNOR MONGOLIA AUTONOMOUS REGION

Based on four aspects, i. e., the landforms, the types, the evolutons and the distribution patterns of the source sediments of the wind sand, this paper deals with the material conditions of the desertification in the area. The interaction of the wind and water is one of the main features of the geomorphical processes. The source sediments of the shifting sand are the wind erosion. and weathering and transportation materials of the basic rock, the fluvio-lacustrine deposits, alluvial deposits,and paleao-eolian deposits which can be divided into 3 parts: silt-sand sandy loess, fine-sand sandy loess and windy sand. There have been at least 14 cycle processes of desertification since the earlier Q_2. The source deposits are cross distributed and expand- ed in two distribution heart terrains that are Mu us sandy land and Qubqi desert and an arch sandy loess belt which orients it self to the south east of the area.