Distribución de la alteración hidrotermal y mineralización (Ag-Pb-Cu-Zn) en la sección 53303350 del depósito Loma de La Plata, distrito Minero Navidad, Chubut

MERCADO MAXIMILIANO; PONS M. J.; FRANCHINI M. ; RAINOLDI A. L.

Córdoba

Congreso; XIII Congreso de Mineralogía, Petrología Ígnea y Metamórfica, y Metalogénesis; 2019

Asociación Mineralógica Argentina, Asociación Geólógica Argentina, y COMPETRO

The mineralization of the epithermal deposit Loma de la Plata is mainly hosted in permeable autobreccia and vesicle-rich andesite facies of the Jurassic Cañadón Asfalto Formation. The analyzed section records the evolution of the hydrothermal activity through three episodes, two of them are barren (E1 and E3) and one responsible for the Ag-Cu (Zn, Pb) mineralization (E2) possibly given by fluid mixing. Early hydrothermal alteration minerals suggest that oxidizing CO2-bearing neutral to alkaline fluids interacted with the host rock. Late illite-smectite to smectite zonation from fault zones indicates a strong structural control for descending CO2-bearing near neutral steam heated waters. This deposit shares mineralogical and textural characteristics with Valle Esperanza, other example of distal mineralization style, and significant differences with Loma Galena, with proximal style mineralization.