Caracterización de los fluidos en sucesivas fases de fracturación en las Cadenas Costero Catalanas y su registro en los filones de Ba-F de baja temperatura

Abstract

In the F-Pb-Zn Berta mine (Catalonian Coastal Ranges), fluid inclusion, stable and radiogenic isotope data have allowed to recognize two different and temporally separated hydrothermal events. The first is characterized by mixing of two fluids of contrasting salinities (from 3 to 20% NaCl eq.) and temperatures (80 to 200°C). The fluid having the lower salinity and higher temperature has a 8 wO around -7,2%o, suggesting a surficial origin. The second event is dominated by low salinity (up to 5% NaCl eq.) and low temperature (120°C) meteoric waters, chemically similar to the nearby La Carriga-Samalus geothermal waters. Strontium isotopes in fluorites suggest a relationship of the hydrothermal episodes to rifting periods of Triassic-jurassic and Miocene age respectively