Stable isotope geochemistry of the Ulldemolins Pb-Zn-Cu deposit (SW Catalonian Coastal Ranges, Spain)

Alfonso, P., Canet, C., Melgarejo, J.C., Mata-Perelló, J.M. and Fallick, A.E. (2012) Stable isotope geochemistry of the Ulldemolins Pb-Zn-Cu deposit (SW Catalonian Coastal Ranges, Spain). Geologica Acta, 10(2), pp. 145-157. (doi: 10.1344/105.000001707)

Abstract

The Pb-Zn-Cu deposit of Ulldemolins occurs within the Carboniferous sedimentary series of the southernmost Catalonian Coastal Ranges. It consists of sulphide-bearing calc-silicate assemblages, with epidote, Ca-amphiboles and Ca-garnet, which develop selectively along a dolomicrite bed near the contact with a granite porphyry. Two mineralisation styles can be differentiated: a) banded and b) irregular. Fluid inclusions and stable isotope compositions of sulphur in sulphides (sphalerite, galena and chalcopyrite) and carbon and oxygen in carbonates (calcite and dolomite) were studied in order to constrain the genesis and the source of mineralizing fluids. Fluid inclusions in sphalerite and calcite are aqueous, liquid+vapour and have a salinity between 1.2 and 7.2 wt% NaCl eq. and homogenization temperatures in the range of 273º to 368ºC. The δ34S(V-CDT) values in the banded mineralisation are mostly between –1.5 and +2.1‰, and those from the irregular mineralisation are between –1.1 and +20.5‰. These δ34S values of the banded mineralisation are in agreement with a magmatic origin of sulphur. In addition, the δ18O(SMOW) values of hydrothermal calcite, from +6.9 to +12.5‰, are consistent with a magmatic origin of the fluids that formed the banded ore deposit. Later, a new input of fluids interacted with the previously formed mineral assemblages and modified part of the deposit, leading locally to an irregular skarn mineralisation.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fallick, Professor Anthony
• Authors: Alfonso, P., Canet, C., Melgarejo, J.C., Mata-Perelló, J.M., and Fallick, A.E.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Geologica Acta
• ISSN: 1695-6133
• ISSN (Online): 1696-5728