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Jiří Zachariáš – Marta Pudilová400Pseudosecondary350Primary300Th-tot (°C)250200PS-SS7bS7aTrend BS?S3SecondaryTrend AS1150100S5-S450Trends "C"00 1 2 3 4 5 6 7 8 9 10Salinity (wt% NaCl eq.)Fig. 6. Salinity vs. total homogenization temperature diagram of primary (P), pseudosecondary (PS) and secondary (S) inclusions. Primary (squaresymbols) and pseudosecondary (diamond symbols) inclusions with vapour, liquid and critical total homogenization are shown by open, black-filledand grey-filled symbols, respectively. Individual groups of secondary inclusions with T FM ~ –32 °C and –49°C to –56 °C are highlighted by open andfilled ellipses, respectively, and by thick lines labelled trend A and trend B, respectively.Th-CO 2 : +11.0 to +28.3 °C (always to L, Fig. 2), Th-tot:+300 to +257 °C (to V), +251 to +215 °C (to L) and +237°C (to C).The microthermometric characteristics of secondaryinclusions are summarized in Table 1. Individual inclusionpopulations, represented by data for each individual secondaryplane, are relatively homogeneous (Fig. 6).Oxygen isotopesTwo samples of vein quartz (quartz-1, massive typefrom vein core) with wolframite were analysed for oxygenisotopes. The measured δ 18 O (SMOW) compositions ofquartz-1 are quite homogeneous (+13.8 and +13.7‰),while that of wolframite slightly varies (+7.6 and +8.0‰).There are three different fractionation factor curves forquartz-wolframite mineral pairs known to date: Landis andRye (1974), Zheng (1992) and Zhang et al. (1994). Ofthese only the theoretical equation of Zheng (1992) givesreasonable estimated temperatures for our quartz and wolframitedata – 360 ±20 °C. [That of Landis and Rye (1974)is not applicable because of small ∆ qtz-wolf difference of6‰ only. Experimental equation of Zhang (1994) yieldedtoo high temperature of 500 ±20 °C that is not supportedby our fluid inclusion data from cogenetic quartz.]The estimated fluid composition (δ 18 O) is +8‰SMOW at 360 °C. If temperatures obtained from primaryfluid inclusion (Th-tot: 350–225 °C) are combined withthe quartz-isotope data, then the δ 18 O composition of correspondinghydrothermal fluid would lie in the interval of+8 to +3‰ SMOW.Discussion of a hydrothermal modelfor the Kasejovice districtThe precipitation of the quartz gangue (quartz-1) is relatedto low salinity aqueous-carbonic fluids (P and PS inclusions),oxygen isotopic signatures (δ 18 O fluid : +8 to162

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