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Resumen:
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The Patricia deposit is a Zn-Pb-Ag polymetallic mineralization located in northeastern Chile, on theborder between the Precordillera and the Western Cordillera of the Andes. The deposit forms part ofthe Paguanta Mining Project which includes two other prospects called Doris and La Rosa. This PhDThesis represent the first scientific study of this deposit and its objective is to characterize, from amineralogical, geochemical and structural point of view, the mineralization of Patricia, to establish ametallogenic model that explains its formation within the regional geodynamic context.In order to achieve the objectives, two field campaigns of one month length each were developed,carrying out an exhaustive lithologic and structural study of the area. This study allowed theelaboration of a geological map, both of the Paguanta Mining Project (1:500), and the mineralizationof the Patricia area (1:100). In addition, it was conducted a representative sampling of the differenttypes of mineralization and lithological units located in the Project area. The techniques used for thesamples study were: optical microscopy of transmitted and reflected light, whole-rock geochemistry,X-ray diffraction, SEM, EPMA, fluid inclusions microthermometry, Raman spectroscopy, LA-ICPMS,stable isotopic analysis of S, Pb, O y H, and U/Pb geochronology.The Patricia mineralization shows a strong structural control, occurring in the form of a system ofsubvertical veins with E-W orientations and embedded in a volcano-sedimentary unit which is mainlyconsisting by breccias and andesitic tuffs with an age of 75 ± 2 Ma (Campanian). Based on structuralcriteria such as vein orientation, presence of sinistral strike-slip faults and sigmoidal structures, it hasbeen concluded that the mineralized veins of Patricia are the result of the progressive deformation of ablock formed between two sinistral strike-slip faults with WNW-ESE orientations. This blockprobably could be part of a pull-apart structure on a larger scale and it could be genetically related tothe Domeyko fault system...
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