Kontrastní typy fluid v inkluzích křemenů z alpské parageneze z oblasti sobotínského masivu
Roč.18,č.2(2011)
Vernířovice and Krásné u Hraběšic as famous sites with quartz crystals are located in the Silesicum, in close proximity, respectively inside the Sobotín Massif. Occurences of low-temperature mineral association, connected with metamorphism of the Late Variscan age, are known at the both sites. Quartz crystals were studied using fluid inclusions. Complex aqueous systems up to 5 mass % NaCl with CO2 were recorded at both locations. Due to the petrography – distinct ratios of aqueous solution and CO2 of fl uid inclusions can be assumed that the crystals were formed from a heterogeneous fluid. The temperature and pressure of crystal forming were estimated at cca 240–310 °C and 40–110 MPa with respect to the Thtot in the range 220–315 °C. The presence of high saline solution with CaCl2 in inclusions is most likely interpreted as secondary fluids trapped in quartz. This type of fluids is defined as Post Variscan in the region.
Silesicum; quartz; fluid inclusions; fluids
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