Get started
Work

Multi-Data Integration for Delineating Listweanization Alteration Zones and Associated Gold Mineralization in the Um-Khasila Area, Central Eastern Desert, Egypt

Year: 2026
Type: preprint
Abstract: Listweanization of ultramafic rocks commonly results in diagnostic alteration mineral assemblages that serve as key indicators of potentially economic mineralization. This study employed ASTER and Landsat 7 ETM+ multispectral data to delineate listweanization alteration zones. Most alteration mineral spectra were extracted using selective Principal Component Analysis (PCA), while the ASTER thermal infrared band ratio (14:12) facilitated silica isolation. ASTER successfully identified argillic, phyllic, and propylitic alteration alongside carbonates and silica, whereas Landsat 7 identified undifferentiated clays and iron oxides. Remote sensing results were subsequently validated through fieldwork and confirmed by petrographic investigations and X-ray diffraction (XRD) analysis, which proved to be an essential approach to facilitate mineral exploration. Furthermore, a fire assay was carried out on rock chip samples, followed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for Au quantification and confirmation of potential gold mineralization. This revealed that higher Au concentrations (up to 944 ppb) are spatially and genetically associated with highly altered carbonate-silica-iron oxide alteration zones coinciding with talc carbonate and listweanite. In contrast, fresh ultramafic and least-altered serpentinite protoliths have depleted gold concentrations (1-5 ppb). The integrated multispectral satellite datasets (ASTER and Landsat 7 ETM+) with fieldwork, petrography, and laboratory analyses (XRD and ICP-AES) improved the precision of delineating key alteration mineral zones associated with listweanization. This joint workflow provides a reliable framework to rapidly prioritize gold exploration targets in the study area and analogous ophiolite-granite-greenstone terranes globally.
DOI: 10.21203/rs.3.rs-11346330/v1
Language: English
Open Access status: green
OpenAlex ID: W7225752386
Cites:
Cited by:
Related to: