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

Yıl 2025, Cilt: 8 Sayı: 1, 17 - 33, 31.12.2025

Mustafa Ceylan , Gökhan Külekçi

Öz

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..

Anahtar Kelimeler

ASTER , Principal Component Analysis (PCA) , Hydrothermal Alteration , Remote Sensing , Complex Tectonic Terrains

Gümüşhane-Aktutan Bölgesinde Hidrotermal Alterasyon Haritalaması için ASTER Verilerine Temel Bileşen Analizi Uygulaması

Öz

Hidrotermal alterasyon haritalaması, özellikle karmaşık tektonik ve mineralizasyon ortamlarına sahip bölgelerde, mineral arama ve jeolojik yorumlamada temel bir rol oynamaktadır. Bu çalışma, Kuzeydoğu Türkiye'deki Gümüşhane-Aktutan bölgesinde hidrotermal alterasyon bölgelerini belirlemek için Gelişmiş Uzay Tabanlı Termal Emisyon ve Yansıma Radyometresi (ASTER) verilerine Temel Bileşen Analizi (PCA) uygulamaktadır. İş akışı, radyometrik kalibrasyon, IAR Yansıma Düzeltme yöntemi kullanılarak atmosferik düzeltme ve VNIR, SWIR ve TIR veri setlerinin bant istiflemesini içermektedir. Alterasyon indeksleri, bant oranı teknikleri kullanılarak oluşturulmuş, ardından kuvars, serisit, kaolinit ve gelişmiş arjilik fazlar gibi temel minerallerin spektral imzalarını geliştirmek için PCA uygulanmıştır. Özdeğer analizi, alterasyon desenlerini karakterize etmek için RGB kompozitleri kullanılarak görselleştirilen optimal bant kombinasyonlarının seçimine rehberlik etmiştir. Sonuçlar, PCA'nın örtüşen spektral yanıtları ayırt etmedeki etkinliğini vurgulayarak, birden fazla mineralin bir arada bulunduğu karışık alterasyon bölgelerinin tanımlanmasını sağlamaktadır.
Bu araştırma, çok spektrumlu ASTER verilerinin PCA tabanlı entegrasyonunun, jeolojik olarak karmaşık arazilerde hidrotermal alterasyon haritalaması için güvenilir ve uygun maliyetli bir yaklaşım sağladığını göstermektedir. Çalışma, seçici PCA'nın özgün bir vakaya özgü uygulamasını sunarak, Gümüşhane-Aktutan bölgesinin mineralojik çerçevesine dair yeni bilgiler ortaya koymaktadır. Bulgular, ASTER verilerinin hidrotermal sistem tespiti potansiyelini doğrulamanın ötesinde, alterasyon haritalamasının iyileştirilmesinde çok değişkenli istatistiksel yöntemlerin değerini vurgulamaktadır. Gelecekteki çalışmalar, haritalama hassasiyetini daha da artırmak için hiperspektral veri kümelerini, saha doğrulamasını ve makine öğrenimi tabanlı sınıflandırmayı entegre edecektir. Bu katkının özgünlüğü, PCA metodolojisini mineral bakımından zengin ancak yeterince araştırılmamış bir alanda ASTER verilerine uyarlamakta ve bölgesel arama stratejileri ve jeolojide uzaktan algılama uygulamaları için önemli sonuçlar sunmaktadır.

Anahtar Kelimeler

ASTER , Temel Bileşen Analizi , Hidrotermal Alterasyon , Uzaktan Algılama , Kompleks Tektonik Araziler

Kaynakça

• El-Hadidy, S. M., & Youssef, M. A. S. (2024). Exploring geothermal energy prospects through radioelement enrichment zones in Gabal Abu Hashim area in southeastern Aswan by geophysical and remote sensing data integration. Scientific Reports, 14, 77393. https://doi.org/10.1038/s41598-024-77393-8
• Hegab, M. A. E. R., & Abou El Magd, I. (2024). Revealing potential mineralization zones utilizing Landsat-9, ASTER and airborne radiometric data at Elkharaza–Dara Area, Northeastern Desert, Egypt. The Egyptian Journal of Remote Sensing and Space Sciences, 27(4), 100–114. https://doi.org/10.1016/j.ejrs.2024.10.005
• Martial, F. E., Ousmanou, S., & Madeleine, N. M. (2025). Mapping and discrimination of the mineralization potential in the Bonako area (Central Cameroon Domain): Insights from Landsat 9 OLI data, GIS fuzzy modeling techniques and field observations. Geosystems and Geoenvironment. https://doi.org/10.1016/j.geogeo.2024.100347
• Vural, A., Akpinar, İ., Sipahi, F., (2021). Mineralogical and Chemical Characteristics of Clay Areas, Gümüşhane Region (NE Turkey), and Their Detection Using the Crósta Technique with Landsat 7 and 8 Images. Natural Resources Research, 30, 3955–3985.
• Liu, Q., Ye, Z., Zhu, C., Ouyang, D., Gu, D., & Wang, H. (2025). Intelligent Target Detection in Synthetic Aperture Radar Images Based on Multi-Level Fusion. Remote Sensing, 17(1), 112. https://doi.org/10.3390/rs17010112
• Seifi, A., Yousefi, S., Aryafar, A., & Hosseinjanizadeh, M. (2025). Evaluation of decision tree on ASTER statistical data for segregating alteration zones in Darrehzar deposit, Iran. Earth Science Informatics. https://doi.org/10.1007/s12145-025-01984-w
• Kalimuthu, R., Porwal, A., & Pandalai, H. S. (2025). Remote mapping of lineaments and hydrothermal alteration zones related to unconformity-related uranium deposits in the Badami Group of the Western Kaladgi Basin, India. Ore and Energy Resource Geology. https://doi.org/10.1016/j.oreoa.2025.100106
• Akinlalu, A. A. (2025). Exploration of iron ore deposits in parts of Kogi State, northcentral Nigeria: Analyses from airborne magnetic and ASTER datasets. Geosystems and Geoenvironment. https://doi.org/10.1016/j.geogeo.2025.100359
• Olomo, K. O., Mohammed, M. Z., & Olomo, O. K. (2025). Multispectral remote sensing expression of lineaments and alteration minerals in part of crystalline rock units of Southwestern Nigeria: Implication on gold prospecting. Ore and Energy Resource Geology. https://doi.org/10.1016/j.oreoa.2025.100091
• Yousif, T. M., Aromolaran, O. K., & Kheiralla, K. M. (2025). Lineaments and hydrothermal alteration mapping in the Arkawit area, Northeastern Sudan: Insights from remote sensing. Arabian Journal of Geosciences. https://doi.org/10.1007/s12517-025-12222-4
• Vural, A., & Kaya, A. (2020). Study on the natural and artificial radioactivity risk of the Aktutan alteration site (Gümüşhane). In Proceedings of the 5th International Congress of Health Sciences and Management (5. Uluslararası Sağlık Bilimleri ve Yönetimi Kongresi), Kırşehir, Turkey.
• Vural, A. (2024). The relationship between hydrothermal alteration and element accumulation in Sessile Oak (Quercus petraea L.): A case study from the Canca hydrothermal alteration zone (Gümüşhane, Türkiye). Turkish Journal of Analytical Chemistry, 9(1), 45–56. https://doi.org/10.51435/turkjac.1494920
• Akinlalu, A. A. (2025). Exploration of iron ore deposits in parts of Kogi State, northcentral Nigeria: Analyses from airborne magnetic and ASTER datasets. Geosystems and Geoenvironment. https://doi.org/10.1016/j.geogeo.2025.100359
• Kalimuthu, R., Porwal, A., & Pandalai, H. S. (2025). Remote mapping of lineaments and hydrothermal alteration zones related to unconformity-related uranium deposits in the Badami Group of the Western Kaladgi Basin, India. Ore and Energy Resource Geology. https://doi.org/10.1016/j.oreoa.2025.100106
• Bai, Y., Wang, J., Jiang, G., Zhou, K., Zhou, S., Mi, W., & An, Y. (2025). Identification of alteration minerals and lithium-bearing pegmatite deposits using remote sensing satellite data in Dahongliutan area, Western Kunlun, NW China. Minerals, 15(7), 671. https://doi.org/10.3390/min15070671
• El-Hadidy, S. M., & Youssef, M. A. S. (2024). Exploring geothermal energy prospects through radioelement enrichment zones in Gabal Abu Hashim area in southeastern Aswan by geophysical and remote sensing data integration. Scientific Reports, 14, 77393. https://doi.org/10.1038/s41598-024-77393-8
• Yamaguchi, Y., Kahle, A. B., Tsu, H., Kawakami, T., & Pniel, M. (1998). Overview of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). IEEE Transactions on Geoscience and Remote Sensing, 36(4), 1062–1071. https://doi.org/10.1109/36.700991
• Rowan, L. C., & Mars, J. C. (2003). Lithologic mapping in the Mountain Pass, California area using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data. Remote Sensing of Environment, 84(3), 350–366. https://doi.org/10.1016/S0034-4257(02)00127-X
• Fazli, S., Taghipour, B., Moore, F., & Lentz, D. R. (2019). Fluid inclusions, S isotopes, and Pb isotopes characteristics of the Kuh-e-Surmeh carbonate-hosted Zn–Pb deposit in the Zagros Fold Belt, southwest Iran: Implications for the source of metals and sulfur and MVT genetic model. Ore Geology Reviews, 109, 615–629. https://doi.org/10.1016/j.oregeorev.2019.04.006
• Hegab, M. A. E. R., & Abou El Magd, I. (2024). Revealing potential mineralization zones utilizing Landsat-9, ASTER and airborne radiometric data at Elkharaza–Dara Area, Northeastern Desert, Egypt. The Egyptian Journal of Remote Sensing and Space Sciences, 27(4), 100–114. https://doi.org/10.1016/j.ejrs.2024.10.005
• Rajan Girija, R., & Mayappan, S. (2019). Mapping of mineral resources and lithological units: a review of remote sensing techniques. International Journal of Image and Data Fusion, 10(2), 79–106. https://doi.org/10.1080/19479832.2019.1589585
• Olomo, K. O., Mohammed, M. Z., & Olomo, O. K. (2025). Multispectral remote sensing expression of lineaments and alteration minerals in part of crystalline rock units of Southwestern Nigeria: Implication on gold prospecting. Ore and Energy Resource Geology. https://doi.org/10.1016/j.oreoa.2025.100091
• Vural, A. (2015). Assessment of metal pollution associated with an alteration area: Old Gümüşhane, NE Black Sea. Environmental Science and Pollution Research, 22(5), 3219–3228. https://doi.org/10.1007/s11356-014-2907-7
• Fathi, A., Lee, T. & Mohebzadeh, H. Allocating Underground Dam Sites Using Remote Sensing and GIS Case Study on the Southwestern Plain of Tehran Province, Iran. Journal of the Indian Society of Remote Sensing, 47, 989–1002 (2019). https://doi.org/10.1007/s12524-019-00961-3
• Chavez, P. S. (1988). An improved dark-object subtraction technique for atmospheric scattering correction of multispectral data. Remote Sensing of Environment, 24(3), 459–479. https://doi.org/10.1016/0034-4257(88)90019-3
• Clark, R. N., Swayze, G. A., Gallagher, A. J., King, T. V. V., & Calvin, W. M. (2003). The U.S. Geological Survey Tetracorder and expert systems for imaging spectroscopy. Journal of Geophysical Research: Planets, 108(E12). https://doi.org/10.1029/2002JE001847
• Yousif, T. M., Aromolaran, O. K., & Kheiralla, K. M. (2025). Lineaments and hydrothermal alteration mapping in the Arkawit area, Northeastern Sudan: Insights from remote sensing. Arabian Journal of Geosciences. https://doi.org/10.1007/s12517-025-12222-4
• Vural, A. (2015). Assessment of metal pollution associated with an alteration area: Old Gümüşhane, NE Black Sea. Environmental Science and Pollution Research, 22(5), 3219–3228. https://doi.org/10.1007/s11356-014-2907-7
• Külekçi, G. (2024). Madencilik Operasyonlarında Segmentasyon Teknolojileri: Uydu ve Dron Verilerinden Bilgi Çıkarmada Derin Öğrenme Yaklaşımları. International Journal of Advanced Natural Sciences and Engineering Researches, 8(11), 732-740.
• Gillespie, A. R., Rokugawa, S., Matsunaga, T., Cothern, J. S., Hook, S. J., & Kahle, A. B. (1998). A temperature and emissivity separation algorithm for Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images. IEEE Transactions on Geoscience and Remote Sensing, 36(4), 1113–1126. https://doi.org/10.1109/36.700995
• Martial, F. E., Ousmanou, S., & Madeleine, N. M. (2025). Mapping and discrimination of the mineralization potential in the Bonako area (Central Cameroon Domain): Insights from Landsat 9 OLI data, GIS fuzzy modeling techniques and field observations. Geosystems and Geoenvironment. https://doi.org/10.1016/j.geogeo.2024.100347
• Sillitoe, R. H. (2010). Porphyry copper systems. Economic Geology, 105(1), 3–41. https://doi.org/10.2113/gsecongeo.105.1.3
• Maxwell, J. C. (1860). On the Theory of Compound Colours, and the Relations of the Colours of the Spectrum. Philosophical Transactions of the Royal Society of London, 150, 57–84. https://doi.org/10.1098/rstl.1860.0005
• Vural, A. (2015). Contamination assessment of heavy metals associated with an alteration area: Demirören, Gümüşhane, NE Turkey. Journal of the Geological Society of India, 86(2), 215–222. https://doi.org/10.1007/s12594-015-0301-9
• Salem, I. A. N., Kamh, S. Z., & Saleh, G. M. (2024). Enhanced geological and radioactive mapping of Gabal Abu Ashayir-Gabal El Bakriyah area, central Eastern Desert, Egypt, using remotely sensing data. Journal of Umm Al-Qura University for Applied Sciences. https://doi.org/10.1007/s43994-024-00194-2
• Hunt, G. R. (1977). Spectral signatures of particulate minerals in the visible and near infrared. Geophysics, 42(3), 501–513. https://doi.org/10.1190/1.1440721
• Lillesand, T. M., Kiefer, R. W., & Chipman, J. W. (2015). Remote Sensing and Image Interpretation (7th ed.). Wiley.
• Vural, A., 2024. Soil geochemistry survey for gold exploration at Kısacık area (Çanakkale, Ayvacık, Türkiye). Periodico di Mineralogia, 93 (2), 61-83" and " Vural A (2017). Gold and Silver Content of Plant Helichrysum Arenarium, Popularly Known as the Golden Flower, Growing in Gümüshane, NE Turkey. Acta Physica Polonica A, 132(3-II), 978-980., Doi: 10.12693/APhysPolA.132.978
• Vural, A., & Aydal, D. (2020). Determination of lithological differences and hydrothermal alteration areas by remote sensing studies: Kısacık (Ayvacık-Çanakkale, Biga Peninsula, Turkey). Journal of Engineering Research and Applied Science, 9(1), 1341–1357.
• Vural, A., Çorumluoğlu, Ö., & Asri, İ. (2017). Remote sensing technique for capturing and exploration of mineral deposit sites in Gümüşhane metallogenic province, NE Turkey. Journal of the Geological Society of India, 90(5), 628–633. https://doi.org/10.1007/s12594-017-0762-0
• Seifi, A., Yousefi, S., Aryafar, A., & Hosseinjanizadeh, M. (2025). Evaluation of decision tree on ASTER statistical data for segregating alteration zones in Darrehzar deposit, Iran. Earth Science Informatics. https://doi.org/10.1007/s12145-025-01984-w
• Vural, A. (2015). Contamination assessment of heavy metals associated with an alteration area: Demirören, Gümüşhane, NE Turkey. Journal of the Geological Society of India, 86(2), 215–222. https://doi.org/10.1007/s12594-015-0301-9
• Vural, A., & Kaya, A. (2020). Study on the natural and artificial radioactivity risk of the Aktutan alteration site (Gümüşhane). In Proceedings of the 5th International Congress of Health Sciences and Management (5. Uluslararası Sağlık Bilimleri ve Yönetimi Kongresi), Kırşehir, Turkey.
• Vural, A (2015). Biogeochemical characteristics of Rosa canina grown in hydrothermally contaminated soils of the Gümüşhane province, Northeast Turkey. Environmental Monitoring and Assessment. 187, 486. Doi. 10.1007/s10661-015-4708-y
• Satellite Imaging Corporation. (n.d.). ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). Retrieved December 9, 2025, from https://www.satimagingcorp.com/satellite-sensors/other-satellite-sensors/aster/
• Reid, J. S. (n.d.). James Clerk Maxwell’s triumphant legacy. University of Aberdeen. Retrieved December 9, 2025, from https://homepages.abdn.ac.uk/j.s.reid/pages/Maxwell/Legacy/MaxTri.html