宁夏红寺堡盆地地表沙漠化现状及其地质主控因素  

THE CURRENT SITUATION OF DESERTIFICATION IN THE HONGSIBU BASIN,NINGXIA,AND ITS MAIN GEOLOGICAL CONTROLLING FACTORS

作　　者：黄婷[1,2] 李振宏 刘锋[2] 崔加伟[2] 董晓朋 赵杨[2] HUANG Ting;LI Zhenhong;LIU Feng;CUI Jiawei;DONG Xiaopeng;ZHAO Yang(School of Earth Sciences and Resources,China University of Geoscience,Beijing 100083,China;Institute of Geomechanics,Chinese Academy of Geological Science,Beijing 100081,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]中国地质科学院地质力学研究所,北京100081

出　　处：《地质力学学报》2018年第4期505-514,共10页Journal of Geomechanics

基　　金：中国地质调查局地质调查项目(DD20160060)

摘　　要：以landsand-TM遥感影像资料提取为基础,详细解译了宁夏红寺堡盆地近30年来地表沙漠化的进程。进一步结合1∶50000区域地质填图成果,系统建立了红寺堡盆地晚更新世区域地层对比格架,恢复了重要演化阶段的岩相古地理格局,地质与地球化学分析相结合,确立了区域沙漠化的物质来源。研究结果认为:1999年国家实施的西部生态移民战略使红寺堡盆地生态环境恶化得到了有效修复,区域沙漠化整体呈现出了稳中有降的变化趋势,但并未得到彻底的有效根治;地表沙丘沙脊的主体走向呈北西—南东向,与大罗山—牛首山构造带、烟筒山构造的主体走向基本一致,具有带状分布的格局;沙漠化物质来源主要受控于上更新统萨拉乌苏组三段湖退序列的疏松湖相砂,具有原地沙漠化的特征;地表风成沙与萨拉乌苏三段湖相砂在主量元素、微量元素和稀土元素特征上具有比较一致性的变化趋势,进一步说明了二者在成因上具有一定的亲源性。该研究成果对区域土地沙漠化的综合防治具有重要的现实指导意义。Based on the landsand-TM remote sensing images, the desertification evolution history of the Hongsibu Basin in the last 30 years is rebuilt. Combining with the 1：50000 geological mapping, the Late Pleistocene sedimentary frame is systematically built and the lithofacies paleogeography for several important evolutional phases of the Hongsibu Basin is reconstructed. Moreover, the provenance of the eolian sand by detailed geological field and sedimentary geochemical works is traced. According to the primary research, several cognitions can be suggested that Although the desertification had not been eliminated, the ecological migration strategy implemented in 1999 effectively curbed the deterioration of the ecological environment and the range of desertification decreased; The sand ridges at the surface with zonal distribution characteristics mainly extend in NW-SE direction which parallels with the strike of the Daluo Mountain-Niushou Mountain tectonic belts, and Yantong Mountain tectonic belts; The eolian sand piled during the desertification mainly derived from the loosened lacustrine sand deposits, the third part of the Upper Pleistocene Salawusu formation sedimented during the regression, and this process is characterized with in-situ desertification; The similarities of the eolian sand at the surface and the lacustrine sand from the third part of the Salawusu formation in major elements, trace elements, and REE aspects revealed the affinity between these two sets of sands. What’ s more, this study contributes a lot to the comprehensive control for the regional desertification in the Hongsibu Basin, Ningxia.

关 键 词：上更新统 萨拉乌苏组 湖相砂 原地沙漠化 红寺堡盆地 

分 类 号：X141[环境科学与工程—环境科学]