数字高程模型在地表过程研究中的应用

Application of digital elevation model to surficial process research

数字高程模型(DEM)是人们研究地表过程、构造地貌的一种行之有效的方法和手段。DEM是地形表面的数字表达,易于三维可视化和统计分析。DEM作为一种空间数据,可以进行各种空间分析,编制平均高程图、山顶面图、谷地面图、局部地形图、平均坡度图和剖面图,从而有效地显示地形特征,预测地表侵蚀量和地形发展趋势。特定盆地充填面的DEM分析是探讨特定地质时期(新生代)以来地表由沉积转入侵蚀、沉积之后隆升过程、隆升速率和剥蚀量、剥蚀速率等地表过程的有效手段,它与大地构造、深部地球物理相结合,可以揭示隆升机制和大陆动力学背景。低起伏侵蚀面的DEM分析有利于定量揭示山脉夷平面分布,结合基岩地质等其他资料综合分析,可揭示侵蚀面的成因,揭示大地构造与地表过程相互关系是未来研究的主要目标之一。

Digital elevation model (DEM) analysis is one of the most effective methods for studying surficial processes and geomorphology. DEM is a digital expression of landform surface, and is of great advantage to three-dimensional visualization and statistical analysis. Different spatial analyses can be obtained, such as summit level map, base level map, local relief, average slope and profile views can be made using DEM as spatial data. DEM data help to display topographic features, and forecast erosional capacity and topographic trends. The DEM analysis of basin fill surface is an effective method to probe into the transition from sedimentation to erosion, uplift after deposition, uplift rate, and erosional capacity and rate. Combined with tectonics and geophysics, it can provide insights into uplift mechanisms and continental dynamics. The DEM analysis of low-relief erosion surface also helps to understand the distribution of planation surfaces in mountainous terrains. DEM analysis, combined with other data, is very useful tool to look into the relationship between tectonics and surficial processes.