Estudio preliminar de la composición química y de las inclusiones fluidas en fluoritas hidrotermales de la sierra de Ancasti, Catamarca, Argentina

IRIARTE, MATÍAS; ALTENBERGER, UWE; SARDI, FERNANDO G.; MONTENEGRO, TERESITA

Congreso; XIII Congreso de Mineralogía, Petrología Ígnea y Metamórfica, y Metalogénesis (XIII MinMet ? IV PIMMA).; 2019

In this paper, a preliminary study about thepetrography and thermometric data of fluid inclusions and REE-composition fromhydrothermal fluorite veins from northwestern region of the Ancasti range, Catamarcaprovince (Argentina) is presented. The fluorite of the veins is accompanied by quartz andchalcedony. The veins are hosted by Upper Devonian-Lower Carboniferous granitoids. Thefluid inclusions study was carried out in granular purple fluorite while the REE-compositionwas obtained in five fluorite-samples of three different veins. The fluid inclusions arevariable in size and shape. They are predominantly biphasic (liquid and gas phases) and theaverage homogenization temperature is 126ºC. The REE geochemistry shows a total contentthat varies from 6.70 to 64.33 ppm (average 25.51 ppm). The LREE/HREE relationship isgenerally greater than 1 and Eu/Eu* ratio varies between 0.66 and 0.81. The diagram Tb/Cavs Tb/La in accordance with geological setting and textural-mineralogical features indicate ahydrothermal origin for these deposits. Additionally, these textures show more than onemineralizing pulse and low formation temperatures.