基于数字剖面的河流阶地与新构造运动研究——以内蒙古西拉木伦河河流阶地为例  

River terraces and neotectonic movement based on digital sections——A case study of terraces of the Xar Moron River,Inner Mongolia,China

作　　者：周文孝[1] 葛梦春[2] 于庆文[3] 李超岭[4] 赵温霞[2] 谢德凡[2] 

机构地区：[1]中国地质大学研究生院,湖北武汉430074 [2]中国地质大学地球科学学院,湖北武汉430074 [3]中国地质调查局,北京100037 [4]中国地质调查局发展研究中心,北京100037

出　　处：《地质通报》2008年第7期995-1001,共7页Geological Bulletin of China

基　　金：中国地质调查局<1:25万林西县幅;锡林浩特市幅区域地质调查>项目资助

摘　　要：野外调查发现在内蒙古东部西拉木伦河流域存在12级阶地序列。利用数字剖面野外系统对该河流阶地剖面的记录完成全程数字化采集,并进行数字剖面桌面系统厚度自动计算和剖面图、柱状图自动生成,发现该阶地序列中T7、T8、T9保存完好,而时代最为古老的T12,根据基座玄武岩形成于上新世—早更新世的年龄,其形成时代应为上新世—早更新世。通过计算新构造运动抬升速率,将其形成、演化过程划分为6个阶段。数据表明,自中新世以来,该地区新构造运动存在一定的周期性,在总体上新构造运动的强度逐渐趋于缓和。During field investigations, 12 terraces were found in the Xar Moron RAver basin, eastern Inner Mongolia. Whole-course digital gathering of records of the river terraces was completed using the digital section field system and thickness automatic calculation and automatic production of sections and columns were performed using the digital section desktop system. The results show that ter- races TT, Ts and T9 in this terrace sequence are well preserved. As the substrata of the terraces--basalts--formed in the Phocene to ear- ly Pleistocene, the oldest T,2 should form. According to the uplift rate of the neotectonic movement, the process of its formation and evolution may be divided into six stages. Since the Miocene, the neotectonic movement of this area showed certain periodicity and generally the intensity of the neotectonic movement weakened gradually.

关 键 词：数字剖面 西拉木伦河 河流阶地 新构造运动 

分 类 号：P623.1[天文地球—地质矿产勘探]