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@article{207379,
        author = {Aduojo Atakpa and Taiwo Olatunji Qudus and Muhammad Rabiu Dahiru and Abdullahi Mohammed Salihu},
        title = {Cloud-Based Multispectral Analysis for Mapping Hydrothermal Alteration Zones in Zamfara State, Nigeria},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {3},
        pages = {649-657},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=207379},
        abstract = {Hydrothermal alteration mapping is a critical step in mineral exploration reconnaissance, particularly in geologically complex terrains such as the Nigerian Basement Complex. This study applies cloud-based multispectral remote sensing techniques to map and characterize hydrothermal alteration zones in Zamfara State, northwestern Nigeria, using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery processed within the Google Earth Engine (GEE) platform. Dry-season ASTER data were atmospherically corrected using the Dark Object Subtraction (DOS) technique, and targeted band ratio expressions were applied to delineate eleven diagnostic mineral assemblages, including Al-OH minerals (kaolinite, illite-muscovite, montmorillonite, alunite-pyrophyllite), iron oxides and hydroxides (hematite, goethite, jarosite), carbonate and Mg-OH minerals (chlorite, epidote), as well as silica (quartz) and sulfate (gypsum) phases. Results reveal a well-defined spatial zonation of alteration assemblages, with argillic and phyllic minerals (kaolinite, illite-muscovite, jarosite, goethite) concentrated in the southern Maru region associated with the Anka and Maru schist belts, while propylitic assemblages (carbonates, Mg-OH minerals) dominate the northern and central zones. This systematic alteration zoning is consistent with a preserved hydrothermal system suggestive of porphyry copper and epithermal gold environments. The derived mineral maps were validated against existing geological maps and known mineralization occurrences, confirming their spatial coherence with documented schist belt geology. The study demonstrates the effectiveness of Google Earth Engine-hosted ASTER analysis as a cost-efficient, scalable reconnaissance tool for targeting high potential zones in underexplored regions of the West African Craton.},
        keywords = {ASTER, hydrothermal alteration, Google Earth Engine, mineral mapping, band ratios,},
        month = {August},
        }