Paper Info
Title
Lithological and Hydrothermal Alteration Mapping of Epithermal, Porphyry and Tourmaline Breccia Districts in the Argentine Andes Using ASTER Imagery.
Abstract
The area of interest is located on the eastern flank of the Andean Cordillera, San Juan province, Argentina. The 3600 km(2) area is characterized by Siluro-Devonian to Neogene sedimentary and igneous rocks and unconsolidated Quaternary sediments. Epithermal, porphyry-related, and magmatic-hydrothermal breccia-hosted ore deposits, common in this part of the Frontal Cordillera, are associated with various types of hydrothermal alteration assemblages. Kaolinite - alunite-rich argillic, quartz - illite-rich phyllic, epidote - chlorite - calcite-rich propylitic and silicic are the most common hydrothermal alteration assemblages in the study area. VNIR, SWIR and TIR ASTER data were used to characterize geological features on a portion of the Frontal Cordillera. Red-green-blue band combinations, band ratios, logical operations, mineral indices and principal component analysis were applied to successfully identify rock types and hydrothermal alteration zones in the study area. These techniques were used to enhance geological features to contrast different lithologies and zones with high concentrations of argillic, phyllic, propylitic alteration mineral assemblages and silicic altered rocks. Alteration minerals detected with portable short-wave infrared spectrometry in hand specimens confirmed the capability of ASTER to identify hydrothermal alteration assemblages. The results from field control areas confirmed the presence of those minerals in the areas classified by ASTER processing techniques and allowed mapping the same mineralogy where pixels had similar information. The current study proved ASTER processing techniques to be valuable mapping tools for geological reconnaissance of a large area of the Argentinean Frontal Cordillera, providing preliminary lithologic and hydrothermal alteration maps that are accurate as well as cost and time effective.
Year
DOI
Venue
2018
10.3390/rs10020203
REMOTE SENSING
Keywords
Field
DocType
ASTER,geology,hydrothermal alteration,mineralization,epithermal,porphyry,magmatic-hydrothermal breccia pipe
Aster (genus),Remote sensing,Epidote,Geochemistry,Igneous rock,Propylitic alteration,Sedimentary rock,Geology,Silicic,Breccia,Lithology
Journal
Volume
Issue
Citations 
10
2
4
PageRank 
References 
Authors
0.51
6
4
Name
Order
Citations
PageRank
Francisco J. Testa140.51
Cecilia Villanueva240.51
David R. Cooke340.51
Lejun Zhang47815.62