Tripathi Mahesh Kumar, Govil H, Chattoraj S L
Department of Applied Geology, National Institute of Technology, Raipur, 492010, C.G, India.
Geosciences Department, Indian Institute of Remote Sensing (ISRO), Dehradun, 248001, U.K, India.
Heliyon. 2020 Feb 27;6(2):e03487. doi: 10.1016/j.heliyon.2020.e03487. eCollection 2020 Feb.
Advanced visible infrared imaging spectrometer-new generation (AVIRIS-NG) airborne Hyperspectral data has 5nm spectral resolution which allows us to identify characteristic spectral signatures of the different altered and weathered mineral assemblage. In this study Airborne AVIRIS-NG hyperspectral data were used to identify the different altered, weathered and clay group of minerals in the Jahajpur, Bhilwara, India. In the study area, different hydrothermal minerals such as Montmorillonite, Smectite and Talc were identified. Apart from this, Goethite/Limonite mineral spectral signatures were identified using the AVIRIS-NG data in the VNIR (visible and near infrared) region of the electromagnetic spectrum. Minerals thus identified were verified by the conventional geological analysis viz. petrography and XRD of the field samples collected from the study area. The results of the conventional geological methods and spectroscopy were in good confirmation with the results found through the analysis of the AVIRIS-NG data. Identified minerals show a good indication of the advance argillic alteration in the study area which stand in confirmation with the geology of the area. Spectral analysis of the AVIRIS-NG data reveals that the reflectance spectra of the airborne AVIRIS-NG Hyperspectral data found promising for mineral identification and mapping.
先进的可见红外成像光谱仪新一代（AVIRIS-NG）机载高光谱数据具有5纳米的光谱分辨率，这使我们能够识别不同蚀变和风化矿物组合的特征光谱特征。在本研究中，机载AVIRIS-NG高光谱数据被用于识别印度比勒瓦尔邦贾哈杰布尔地区不同蚀变、风化的矿物以及粘土类矿物。在研究区域内，识别出了不同的热液矿物，如蒙脱石、绿土和滑石。除此之外，利用AVIRIS-NG数据在电磁光谱的可见光和近红外（VNIR）区域识别出了针铁矿/褐铁矿矿物的光谱特征。如此识别出的矿物通过传统地质分析手段进行了验证，即对从研究区域采集的野外样本进行岩相学分析和X射线衍射分析。传统地质方法和光谱分析的结果与通过AVIRIS-NG数据分析得出的结果高度吻合。识别出的矿物很好地表明了研究区域内存在高级泥化蚀变，这与该区域的地质情况相符。AVIRIS-NG数据的光谱分析表明，机载AVIRIS-NG高光谱数据的反射光谱在矿物识别和制图方面很有前景。
