Discrimination of Different Erosion Levels of Porphyry Cu Deposits using ASTER Image Processing in Eastern Iran： a Case Study in the Maherabad, Shadan, and Chah Shaljami Areas

• Published in: Acta geologica Sinica (Beijing) Vol. 88; no. 4; pp. 1195 - 1213
• Main Authors: KARIMPOUR, Mohammad Hassan, MAZHARI, Nazi, SHAFAROUDI, Azadeh Malekzadeh
• Format: Journal Article
• Language: English
• Published: Richmond Blackwell Publishing Ltd 01.08.2014; Wiley Subscription Services, Inc; Research Center for Ore Deposit of Eastern Iran, Ferdowsi University of Mashhad, P.O.Box 91775-1436, Mashhad, Iran
• Edition: English ed.
• Subjects: Alterations; ASTER; Blocking; Copper; DEPOSITION; Discrimination; EROSION; Image processing; Lut block; MICA; MTMF; Porphyry copper deposits; PORPHYRY ORES; SAM; Spectra; 伊朗; 侵蚀程度; 斑岩型铜矿床; 斑岩铜矿床; 水; 浅成低温热液; 遥感影像; Lut block; Porphyry copper deposits; MTMF; ASTER; SAM
• ISSN: 1000-9515; 1755-6724
• DOI: 10.1111/1755-6724.12283

The Lut block, eastern Iran, is one of the most extensive Cenozoic magmatic rocks, that show suitable targets for porphyry Cu-Au and high-sulfidation epithermal Au related to porphyry Cu-Au mineralization. In this study, Advanced Spaceborne Thermal Emission and Reflection Radiometer （ASTER） was used to identify different erosion levels of three porphyry Cu deposits, including Maherabad, Shadan, and Chah Shaljami, located in the Lut block volcanic-plutonic belt. Alteration minerals, including kaolinite, dickite, alunite, jarosite, epidote, chlorite, montmorillonite, muscovite, biotite, orthoclase, gypsum, and quartz, are selected to map different alteration zones and erosion levels. Distributions of end-members are mapped by using the SAM and MTMF in VNIR and SWIR of ASTER bands and the results are evaluated against the field studies. For some end-members, the results of SAM processing are more reliable compared to the MTMF because the latter looses field spectra. The use of angle threshold in the SAM, and MF-score and infeasibility value in the MTMF or low abundance of some end-members, and finally comparison of output images of spectral processing show good correlation with alteration maps. Differentiation and explanation of various erosion levels of porphyry Cu deposits are done successfully by using the ASTER sensor data.