Identification of hydrothermal altered/weathered and clay minerals through airborne AVIRIS-NG hyperspectral data in Jahajpur, India

Heliyon. 2020 Feb 27;6(2):e03487. doi: 10.1016/j.heliyon.2020.e03487. eCollection 2020 Feb.

Abstract

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.

Keywords: AVIRIS-NG; Argillic; Clay; Geology; Goethite; Jahajpur; Limonite; Spectroscopy; XRD.