Chapter 12 - Mineral exploration using multispectral and hyperspectral remote sensing data

Abstract

In many environments where traditional field surveys are difficult and time-consuming, the remote sensing (RS) technology enables quick delineation of mineralized zones over wide areas at minimum cost and effort. Minerals and rocks are identified based on their mineral absorption properties present in the visible, near-infrared (VNIR), shortwave infrared (SWIR) (0.4–2.5μm), and thermal infrared (TIR) (8–12μm) wavelength regions. Iron oxides and hydroxides are charactered in the spectra region of VNIR (0.4–1.1µm) region, whereas the SWIR absorption features (2.0–2.5µm) distinguish the spectra of carbonates, clay minerals, and sulfates. The TIR distinguish the spectra of silicates. Multispectral (e.g., Landsat 7, Landsat 8, ASTER, and Sentinel-2A) and hyperspectral (e.g., AVIRIS and Hyperion) RS data are used for mineral exploration in various environments to delineate structural elements that may have controlled mineralization as well as alteration zones. Mineral exploration in these environments is examined using numerous image processing techniques, such as minimum noise fraction, principal component analysis, band ratio, matched filtering, and image classification. This chapter addresses several mineral exploration techniques and methods including spectral properties of minerals and rocks, and selected case studies.