Fluid evolution associated with the early Proterozoic Rauhala Zn-Cu-Pb sulphide deposit in Ylivieska, Western Finland
European Journal of Mineralogy Volume 4 Number 5 (1992), p. 1069 - 1078
published: Oct 14, 1992
manuscript accepted: Mar 3, 1992
manuscript received: Jun 12, 1991
ArtNo. ESP147050405008, Price: 29.00 €
Abstract The results of a fluid inclusion study of massive and disseminated ores from the Rauhala deposit, western Finland, show three different fluid inclusion types: (1) CO2-CH4 (<22 mol% CH4), (2) CH4, (3) H2O (0.4-21 eq.wt.% NaCl), and an additional type-E ("empty") inclusion. Fluid inclusion geothermobarometry shows that the ores were remobilized between 2.7-1.2 kb and 460-300 °C in a fluid environment varying from a saline (15-21 eq.wt.% NaCl) aqueous solution to a retrograde CH4 fluid. Evolution of gaseous fluids is mainly attributed to metamorphic and deformational processes.