基于DEM的内蒙古狼山地貌参数提取及其构造抬升的差异性分析

EXTRACTION OF TECTONIC GEOMORPHOLOGIC PARAMETRES BASED ON DEM AND ANALYSIS OF DIFFERENCE ON TECTONIC ACTIVITY ABOUT LANGSHAN MOUNTAIN,INNER MONGOLIA

基于30 m分辨率DEM数据,利用Arc GIS10.0对内蒙古狼山东南坡河流流域地貌参数进行提取,精确计算了其中15条规模较大的北西—南东向河流的面积-高程积分值（HI）,并据此对河流发育阶段以及构造运动进行分析。研究结果显示有8条河流的HI值处于0.3~0.6之间,属于河流发展的壮年阶段;7条河流的HI值大于0.6,为幼年期,未出现老年期河流。狼山西南部河流河谷V1—V14的HI值变化平缓,波动幅度不大,构造运动呈现出先增强后减弱的态势;中北部河流V14—V22的HI值变化较剧烈,尤其是V14—V19,呈明显上升趋势,河流受侵蚀后残存体积增多,构造运动活跃性下降;V19以北HI值持续下降,其构造运动的活跃性增加。由此认为狼山从西南到东北总体呈现增强—减弱—增强的差异性运动状态,该结论与前人所做山前构造地貌研究结果较为一致。

This paper extracted the drainage basins of 15 rivers on the southeast slope of Langshan Mountain and narrowly calculated their HI values using Arc GIS10. 0 based on 30 meter resolution DEM data,then analysed the tectonic activities and geomophological evolutions in this region. The results showed that the HI values of 8 rivers were between 0. 3 and 0. 6,indicating that these rivers were in their mature stage; the HI values of 7 rivers were greater than 0. 6,stating clearly that these rivers were in their juvenile stage. Moreover,there were no rivers in old age. The HI values of V1 ~ V14 changed gently,with the tectonic movement first increasing and then decreasing. The area-altitude points of V14 ~ V22 changed tempestuously,especially rivers V14 ~ V19,which showed a clear upward trend and the river eroded remnant volume increased in the result the tectonic activity decreased. HI values the rivers north of V19 continued to decline,and its tectonic activity increased. The Langshan Mountain was suggested in enhanced-weakening-enhanced diversity state of motion from the southwest to the northeast with the conclusion of previous work in tectonic geomorphology of the consistent results.