La Esperanza mining prospect, new indications of a Cu-Mo-Au porphyry, Sigchos-Cotopaxi
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Abstract
The investigation presents data related to new porphyry located in the northcentral part of the Western Cordillera, north of Ecuador, La Cocha de San Isidro sector, Sigchos Canton. The geology of the area corresponds to volcanosedimentary rocks, andesitic lavas of oceanic crust attributed to the Macuchi Formation of the Eocene. It presents tertiary intrusions type: tonalitas, diorites and granodiorites related with the mineralization. For the identification of this prospect, a statistical reinterpretation and treatment of geochemical data of historical river sediments and rock samples from outcrops in first and second order drains was performed; identifying anomalies of copper, molybdenum, gold and silver. In the study area, I have identified similar three areas of mineral interest called San Isidro, San Miguelito and La Chalá, related to dioritic, quartz-dioritic and tonalitic intrusives, which presents strong silicification and propylic alteration, local potassium alteration in the core of system, associated with stockwork phases of Qz + sulfides. Important copper values of up to 0.43% are reported; in molybdenum 0.04%, and in gold up to 0.86 g / t. Based on the geological data and laboratory results of the samples, it can be interpreted that these areas correspond to a copper-molybdenum-gold porphyry deposit.
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