小型机载高光谱成像仪在高山峡谷地区遥感地质岩性解译应用

The application of a small airborne hyperspectral imaging spectrometer on remote sensing geology and lithology interpretation in alpine canyon regions

【研究目的】水利工程项目通常位于地势险峻的山区,交通不便、环境恶劣,勘察工作十分艰苦。同时,视界限制使地质人员不能整体上掌握地质体的面貌,尤其在高山峡谷地区,人力、物力及时间成本耗费巨大。高光谱遥感技术在地质领域中的应用主要集中在地物分布反演方向,通过未知地物与已知矿物之间相同的特征吸收峰来判定地物种类,利用其极高的光谱分辨率、空间分辨率和“图谱合一”的特性,可对高山峡谷区的地物目标进行精细分类,从而提高地质调查工作的效率,降低风险。【研究方法】中水北方勘测设计研究院利用中国地质调查局南京地质调查中心自主研发的高效率小型机载高光谱成像光谱仪,首次对位于甘南藏族自治州迭部县高山峡谷地带的工作区进行高光谱遥感对地探测,获取了工作区航空高光谱影像数据。采用最小噪声分离法、波段比值分析法对高光谱遥感数据进行岩性解译。【研究结果】结果表明:以白龙江为界,以北大部分为板岩及第四系黄土,以南则大部分为灰岩。解译结果与已知区域地质图岩性分布一致。【结论】本次研究验证了国产高光谱成像仪的可靠性与实用性,同时提高了水利工程前期地质勘查工作的效率和水平,并提供了险要地形地质勘察的一手资料。

This paper is the result of geological survey engineering.[Objective]Water conservancy projects are usually located in mountainous areas with steep terrain,inconvenient transportation and harsh environment,so that the survey work is very difficult.Meanwhile,the limitation of horizon makes it impossible for geologists to grasp the features of geological units as a whole,especially in high mountain and canyon areas.The application of hyperspectral remote sensing technology in the geological field mainly focuses on the extraction and identification of geological composition.The types of surface features are determined by similarity of spectral features between unknown geological units and known mineralsand rocks.Using its extremely high spectral resolution,spatial resolution and the advantage of union of imagery and spectrum,the technology can be applied on fine classification of rock types in alpine and canyon areas,so as to improve the efficiency of geological survey and reduce costs and risks.[Methods]This paper introduces Bei Fang Investigation,Design&Research Co.,Ltd.adopting the SSMAP-II small short-wave infrared imaging system independently developed by the Nanjing Center,China Geological Survey in the project of"Research on Remote Sensing Geological Interpretation Methods Based on Hyperspectral Image Data",taking a helicopter as platform to carry out hyperspectral ground-based remote sensing surveys in Diebu County,Gannan Tibetan Autonomous Prefecture.The surveys aerial hyperspectral image data of the study area,then used MNF minimum noise fraction(MNF)method and band ratio analysis method to interpret the lithology.[Results]The interpretation result is basically consistent with the lithology distribution of the known regional geological map,providing first-hand information for the water conservancy projects of the dangerous areas.[Conclusions]This research improves the work efficiency and the level of geological exploration,meanwhile it also verifies the reliability and practicability of the domestic hyperspectral imaging spectrometer.