Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Conditions of greisenization at the Sn-W deposit Krásno-Horní Slavkov: constraints from fluid inclusions study
Abstract
A fluid inclusion study was conducted on ore-vein and rock samples collected from Krásno-Horní Slavkov Sn-W ore district. Primary fluid inclusions hosted by quartz, topaz, cassiterite and apatite are aqueous, two-phase (L+V), and exhibit homogenization temperatures mostly between 350 and 400 °C (homogenization mode to liquid, vapour and critical). Salinity of the fluid does not exceed 7 wt. % NaCl equiv. Locally, small admixture of C02 was found (up to 12 mol. %). The formation PT-conditions were located at -350-400 °C and 180-570 bar being comparable to other Sn-W deposits in the Saxothuringian Zone. The absence of high-salinity fluids can be related to mixing of magmatic fluids with low-salinity external waters, or it is artefact of sampling restricted to apical part of the cupola.
