Services on Demand
Journal
Article
Indicators
Cited by SciELO
Access statistics
Related links
Cited by Google
Similars in SciELO
Similars in Google
Share
Boletín de Ciencias de la Tierra
Print version ISSN 0120-3630
Abstract
ALVARAN ECHEVERRI, MAURICIO; NARANJO SIERRA, EDWIN and ZAPATA CARDONA, ELISELDER. CU SKARN IN RÍO FRÍO MINE: MINERALOGICAL, METALOGRAPHIC AND MICROTHERMOMETRIC CHARACTERISTICS. Bol. cienc. tierra [online]. 2011, n.29, pp.7-20. ISSN 0120-3630.
The Cu skarn-type mineralization in the Rio Frio mine seems to be related to Jurassic-Cretaceous rocks (Stock of Payandé) that intrude Triassic limestones belonging to Payandé Formation. Ore-body mapping, shows several zones, whose boundaries are gradual and the garnet color is controlled by the distance up to intrusive contact: the first zone corresponds to a fresh tonalite-cuarzodiorite, the second one corresponds to the endoskarn, the third one corresponds to the exoskarn: a prograde stage, characterized by garnet and pyroxene in lesser extent, and a retrograde stage, with the mineralization (iron oxides, iron and copper sulfides), actinolite-tremolite, euhedral quartz and calcite. Finally the marble zone with wollastonite and garnet. The most important textural relationships, between ore minerals are the martitization textures, exsolution textures, pseudo-eutectic textures and selective replacement textures. Fluid inclusions data from prograde garnet indicate a fluid with salinities of 25.76-26.12% NaCl and homogenization temperatures (Th) >580°C. Primary fluid inclusions in quartz, from the retrograde stage, indicate a fluid with salinities between 14.15-16.52% NaCl and homogenization temperatures between 270°-320°C. This is consistent with the presence of cubanite exsolved in chalcopyrite (geothermometer), indicating, according to Ramdorh (1980), temperatures between 250°-300°C. The minimal theoretical pressure is 211-230 bars, which correspond to minimal depths 800-1100m and minimal temperatures of formation of 300°-330°C for the retrograde skarn
Keywords : Cu Skarn; Stock of Payandé; fluid inclusions; cubanite; geothermometers; Tolima; Colombia.