LiDAR技术在活动构造研究中的应用

LiDAR Survey in Active Tectonics Studies:An Introduction and Overview

沿断裂带的大比例尺地貌填图是活动构造研究的重要基础。传统方法一般通过遥感、航片解译以及典型地点的实地测量进行详细填图。因此传统方法一般只能获得二维变形特征,或者局部的三维变形。激光雷达测量(Light Detection And Ranging-LiDAR)技术优势为对地貌的高精度、全方位、三维直接测量,可以为活动构造研究提供沿整条断裂带的高精度地貌高程基础数据。基于LiDAR数据的量化分析是未来活动构造研究的趋势。目前,美国、欧洲、日本以及我国台湾地区等均已经开展沿主要活动断裂带的大规模机载LiDAR测量。与传统方法相比,LiDAR技术在森林覆盖区和城区的活动断裂填图中具有巨大的优势,在沿断裂位错测量上也更精准,更有效。并且震前与震后LiDAR数据对比也是研究同震变形特征、探索断裂发震模式的重要手段。本文综述LiDAR技术在活动构造研究中的主要应用,介绍LiDAR技术在活动构造研究中的优势与前景。分析表明,激光雷达技术在活动构造研究中的应用势在必行,沿国内主要活动断裂带的机载LiDAR测量将成为未来国内活动断裂研究基础数据获取的重要手段。

The active fault mapping is the basis of active tectonics studies. Traditionally, the mapping is conducted by combining of interpretations of remote sensing images and aerial photographs, and field survey at typical sites along the fault. However, these methods are time consuming, and could only obtain the deformation patter along the fault at some typical sites, not along the whole fault strand. The light detection and ranging （LiDAR） survey can directly measure the elevation of the bare ground surface with high precision, which could provide the highest resolution data for active fault mapping along the entire fault strand so far. Recently, LiDAR surveys along major active faults are widely conducted in American, Europe, and Japan, even in Taiwan province of China. In active fault mapping, LiDAR method has advantages over traditional field investigations especially in forestry and cities. Moreover, displacement measurements is efficient, accurate and of high precision based on high resolution LiDAR data; differencing pre-and post-earthquake LiDAR data is efficient in detecting co-seismic deformation pattern along the seismogenie faults. In this paper, we review the major researches of LiDAR surveys in active tectonics researches; and introduce the major advantages and prospect of LiDAR survey. In future, statewide airborne LiDAR survey along the major active faults will be imperative in China; hence, LiDAR data will be the major data source for active tectonics studies.