Radiometric mapping and spectral based classification of rocks using remote sensing data analysis: The Precambrian basement complex, NW Nigeria

Mapping and litho‐geophysical classification of potential mining areas by spatial remote sensing and helicopter‐borne gamma‐ray spectrometry (Tikirt, Anti‐Atlas, Morocco)

“…A ternary image was made by integrating the maps of the three radioelements into a single red, green and blue image, with the potassium map in red, thorium in green and uranium in blue (Figure 8). The ternary image is a very efficient average in displaying radiometric data (Abd El Nabi, 2013; Aisabokhae & Osazuwa, 2021; Almasi et al., 2014; Ebele et al., 2021; Elkhateeb & Abdellatif, 2018; Grochowski et al., 2019). It allows seeing the distribution of the concentrations of radioactive elements in the different rock units.…”

“…Other authors have pointed out that the combination of remote sensing data with geophysical methods, especially airborne gamma‐ray spectrometry, offers more accurate and better interpreted results due to the influences and correlations of some types of alteration detected by remote sensing (e.g. clay alterations and iron oxides) on the radioactive elements K, eU and eTh distribution (Aisabokhae & Osazuwa, 2021; Badr, 2021; Dentith & Mudge, 2014, pp. 222; Ghoneim et al., 2021; Mamouch et al., 2022; Riahi et al., 2022, 2021).…”

Mapping of favourable mining areas in the Tiouit area by multispectral remote sensing and airborne gamma-ray spectrometry coupled with geochemical data (Eastern Anti-Atlas, Morocco)

“…The identification of hydrothermal alteration zones is an important phase in mineral exploration. The alteration produces distinctive mineral assemblages with specific spectral absorption characteristics in the visible and near-infrared (VNIR), across the wavelength regions of the short-wave infrared (SWIR) (0.4–2.5 μm) and/or thermal infrared (TIR) (8–14 μm) (Sabins 1999; Abrams et al 2002; Ranjbar et al 2011; Beiranvand Pour and Hashim 2014; Chattoraj et al 2020; Aisabokhae and Osazuwa 2021). Porphyry deposits are generally associated with zonation of propylitic, argillic, phyllic, and potassic hydrothermal alteration.…”

“…The used ASTER sensor allows a rapid discrimination and mapping of the settled alteration zones by the visible variants, near, and mid-infrared spectral bands. However, spatial remote sensing cannot detect a potassic alteration characterized by feldspathic minerals (Zoheir and Emam 2014; Hassan and Sadek 2017; Aisabokhae and Osazuwa 2021). Helicopter gamma-ray spectrometry is a passive geophysical method that addresses this problem by measuring the concentration of radioactive elements, potassium (%), uranium (ppm), and thorium (ppm) concentrations (Bierwirth and Brodie 2008; Faruwa et al 2021).…”

“…Thus, the hydrothermal alteration ores (sericite, biotite, K-feldspar) can be detected and tracked using gamma-ray spectrometry. During the intense hydrothermal alterations, the enrichment in 40 K is accompanied by the depletion of 238 U and 232 Th (Sanderson et al 2004; Aisabokhae and Osazuwa 2021). The reports of radioelements in K, U, and Th are applied to provide a better resolution of elemental variations than primary channels.…”