Implications of new hyperspectral satellites for raw materials exploration

Abstract

Hyperspectral remote sensing already is important in geoscientific research in the fields of geology, soil, exploration and mining. New hyperspectral satellite systems are already in operation (e.g. PRISMA and DESIS; Caporusso et al. 2020; Alonso et al. (Sensors 19(20):4471–4515, 2019)) and more systems are planned e.g. the European Copernicus Next Generation Hyperspectral Satellite CHIME (Nieke and Rast 2018). The German system EnMAP was successfully launched into space on 1st of April 2022 (DLR 2022). The potential of hyperspectral airborne and satellite borne data for mining-related applications is discussed. Investigated are the information contents of hyperspectral data for exploration target recognition and their dependency on spatial resolutions of different sensor platforms. Airborne data offer high spatial resolution of 2.5 m with limited areal data acquisition, whereas hyperspectral spaceborne sensors guaranty nearly worldwide data availability with the same spectral characteristics but medium spatial resolution (30 m). The aspects of high spectral resolution and high versus medium spatial resolution targeted mineral mapping is investigated. The methodological concept includes processing aspects, standardized data availability for mineral mapping and mineralization targeting for operational application, to maintain/allow application of hyperspectral data even for non-remote sensing experts. Based on hyperspectral airborne data acquired in the Aggeneys region in South Africa, spaceborne hyperspectral data are simulated following the EnMAP specifications, and the concept for targeted mapping of surface alterations of a lead zinc deposit is discussed.

Eliminating the interference of water for direct sensing of submerged plastics using hyperspectral near-infrared imager

“…With the aim of detecting plastics from space using hyperspectral sensors, several satellite products have been recently launched. The PRecursore IperSpettrale della Missione Applicativa (PRISMA) mission carries a hyperspectral sensor with spectral coverage of 400–2500 nm and resolution of < 15 nm, which is fitted well to the sensitive range for plastics 50 , with a relatively coarse ground resolution of 30 m. Sensors with similar spectral coverage and ground resolutions were launched aboard the Environmental Mapping and Analysis Program (EnMAP) mission (420–2450 nm; 30 m) and the Gaofen-5 mission 39 , 51 – 53 . The Hyperspectral Imager Suite (Hisui) sensor that was launched to the International Space Station in 2019 provided global coverage in addition to the coverage features mentioned above (400–2500 nm, 20–30 m) 54 .…”

Imaging Spectroscopy for the Mining Life Cycle: A Guide for Drone Applications

“…Hyperspectral remote sensing has traditionally been employed in mineral exploration, and the exploration sector is responsible for the majority of published case studies over the past decades [8,12,[98][99][100]. This has been accomplished mainly by using airborne hyperspectral and/or satelliteborne multispectral datasets at regional scale, with a limited number of studies focused on mineral mapping at a deposit scale prior to drilling.…”

“…They integrated the results with geochemical, geophysical and geological evidence maps using the fuzzy logic to generate a drilling favourability map. The new generation of spaceborne hyperspectral imaging such as PRISMA, EnMAP, and GaoFen-5 (GF-5) are also predominantly used for mineral exploration and alteration/lithologic mapping purposes [98,[104][105][106][107]. Yet, the high spectral resolution (<10nm) and high SNR (>400:1) of these imaging systems can find numerous applications within the mining sector, as outlined in this paper.…”

Spectral Library of European Pegmatites, Pegmatite Minerals and Pegmatite Host-Rocks – the GREENPEG project database

“…PRISMA (Precursore Iperspettrale della Missione Applicativa) is an Italian Earth observation satellite launched in March 2019 that has a spectral range of 400-2500 nm (Guarini et al, 2018), and EnMAP (Environmental Mapping and Analysis Program) is a German hyperspectral satellite launched in April 2022 that has a spectral range of 420-2450 nm (Chabrillat et al, 2022). Both satellite products have a spatial resolution of 30 m and are expected to be used for a wide range of applications, including land use and land cover mapping as well as mineral and resource exploration (Cardoso-Fernandes et al, 2022a;Lazzeri et al, 2021;Santos et al, 2022a;Schodlok et al, 2022;Vangi et al, 2021;Wocher et al, 2022). To make such applications more successful, it is fundamental to provide researchers and other users with mineral and rock reference spectra in an open, ready-to-use format.…”