Fluidos asociados a la formación de epidota + (clorita + cuarzo) en las pegmatitas del plutón de La Cabrera (Sistema Central Español)

Abstract

Fluids related to the epidote+chlorite+quartz and calcite (+laumontite) alterations present in the cores of pegmatites from La Cabrera pluton have been determined. Two types of fluids are in volved: a) A low salinity (0.4-4.5 wt% NaCl equiv.) NaCl-H20 fluid is the responsable for the first type of alteration. Temperature was probably close to 3000º b) A moderate to high salinity (15.3-24.5 wt% NaCl equiv.) heterogeneous (liquid + gas) CaCI2-NaCI-H20 fluid was in volved in the second alteration under conditions of Pfluid probably very close to hydrostatic. These alterations probably took place as discrete hydrothermal events of different ages.