Abstract: With the development of photogrammetry technology and the popularity of unmanned aerial vehicles (UAVs)technology in recent years, using UAV photogrammetry technology to rapidly acquire high precision and high resolution topographic and geomorphic data on the fault zone has gradually become an important technical means. This paper first summarizes the basic principle and workflow of a new digital photogrammetry technology, SfM (Structure from Motion), which is simple, efficient and low cost. Using this technology, we conducted aerial image acquisition and data processing for a typical fault landform on the northern of Caka Basin in Qinghai. The digital elevation model (DEM)with 6.1cm/pix resolution is generated and the density of point cloud is as high as 273 points/m². The coverage area is 0.463km². Further, the terrain and slope data parallel to the fault direction are extracted by topographic analysis method, and combined with the contour map and the slope diagram generated by the DEM, a fine interpretation and quantitative study of complex multilevel geomorphic surfaces is carried out. Finally, based on the results of sophisticated interpretation of geomorphology, we got the vertical displacements of the T₁ terrace to the T₃ terrace as (1.01±0.06)m, (1.37±0.13)m and (3.10±0.11)m, and the minimum vertical displacements of the T₄ terrace and the T₅ terrace as (3.77±0.14)m and (5.46±0.26)m, respectively, through the topographic profile data extracted by DEM. Such vertical displacement parameters are difficult to obtain directly by traditional remote sensing images, which shows the great application prospect of UAV photogrammetry technology in the quantitative study of active tectonics.

Key words: UAVs, photogrammetry technology, DEM, faulted geomorphology, active tectonics

摘要： 近年来，随着摄影测量技术的发展以及无人机技术的普及，利用无人机摄影测量技术快速获取断裂带上高精度和高分辨率的地形地貌数据已成为1种重要的技术手段。文中首先介绍了1种简单高效且成本较低的新型数字摄影测量技术——SfM（Structure from Motion）方法的基本原理与作业流程，并选取青海茶卡盆地北缘断裂上1个典型的断错地貌点进行了无人机航空影像数据的采集和处理，最终生成了空间分辨率为6.1cm的高分辨率数字高程模型（DEM），点云密度高达273点/m²，覆盖面积达0.463km²。其次，利用地形剖面分析方法提取了平行于断层方向的地形剖面和坡度剖面等数据，结合基于DEM生成的等高线图和坡度图，对复杂的多级地貌面进行了精细的解译和定量研究。最后，基于地貌精细解译的结果，通过DEM提取的地形剖面数据确定了T₁—T₃阶地的垂直位移分别为（1.01±0.06）m、（1.37±0.13）m和（3.10±0.11）m，T₄和T₅阶地垂直位移的下限分别为（3.77±0.14）m和（5.46±0.26）m，获取了通过传统遥感影像难以直接获得的垂直位移信息，展示了无人机摄影测量技术在活动构造定量研究中广阔的应用前景。

关键词: 无人机, 摄影测量技术, DEM, 断错地貌, 活动构造