Application of Principal Component Analysis to ASTER Data for Hydrothermal Alteration Mapping in the Gümüşhane–Aktutan Region

Authors : Mustafa Ceylan, Gökhan Külekçi

Pages : 17-33

View : 99 | Download : 112

Publication Date : 2025-12-31

Article Type : Research Paper

Abstract :Hydrothermal alteration mapping plays a fundamental role in mineral exploration and geological interpretation, particularly in regions with complex tectonic and mineralization settings. This study applies Principal Component Analysis (PCA) to Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data for delineating hydrothermal alteration zones in the Gümüşhane–Aktutan area, Northeastern Turkey. The workflow included radiometric calibration, atmospheric correction using the IAR Reflectance Correction method, and band stacking of VNIR, SWIR, and TIR datasets. Alteration indices were generated through band ratio techniques, followed by PCA to enhance spectral signatures of key minerals such as quartz, sericite, kaolinite, and advanced argillic phases. Eigenvalue analysis guided the selection of optimal band combinations, which were visualized using RGB composites to characterize alteration patterns. The results highlight PCA’s effectiveness in differentiating overlapping spectral responses, enabling the identification of mixed alteration zones where multiple minerals coexist. This research demonstrates that PCA-based integration of multispectral ASTER data provides a reliable and cost-efficient approach for hydrothermal alteration mapping in geologically intricate terrains. The study offers an original case-specific implementation of selective PCA, presenting novel insights into the mineralogical framework of the Gümüşhane–Aktutan region. Beyond confirming the potential of ASTER data for hydrothermal system detection, the findings emphasize the value of multivariate statistical methods in refining alteration mapping. Future work will integrate hyperspectral datasets, field validation, and machine learning-based classification to further enhance mapping precision. The originality of this contribution lies in adapting PCA methodology to ASTER data in a mineral-rich yet underexplored area, offering significant implications for regional exploration strategies and remote sensing applications in geology..
Keywords : ASTER, Temel Bileşen Analizi, Hidrotermal Alterasyon, Uzaktan Algılama, Kompleks Tektonik Araziler

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