Description
| - Kateřinohorský granit tvoří peň o průměru asi 100 m 2 km záp. od Hora svaté Kateřiny. Intrudoval ve dvou pulsech: 1. středně zrnitý neporfyrický biotitický granit tvoří převážnou část pně, a 2. jemnozrnný řídce drobně porfyrický leukogranit. Chemická charakteristika granitů odpovídá A-typu taveniny: granity jsou jen nepatrně peraluminické (ASI=1.05), obohacené o fluor (kolem 0.5 % F), Rb (900-1200 ppm), Nb (60-80 ppm), Ta (10-15 ppm), Th (30-50 ppm), Zr (100-160 ppm), Y (74-157 ppm) a Be (5-19 ppm.), a ochuzené fosforem (0.1 wt% P2O5). Oba granity obsahují krystaly pertitu v základní hmotě složené z křemene, K-živce, albitu a Li-annitu. Běžnými magmatickými akcesoriemi jsou fluorit, magnetit a zirkon. V menším množství je přítomen topaz, beryl, xenotim, monazit, thorit, kasiterit, kolumbit a další Nb,Ta,U-fáze. Černovit, rhapdophan, bastnäsit a Ce- oxyfluoridy jsou spolu s Fe-oxidy and hydroxidy produkty intenzivní hydrotermální alterace.Přibližné stáří granitu je 310+- 14 Ma. (cs)
- The Hora Svaté Kateřiny granite forms a small stock in the Krušné Hory / Erzgebirge Mts. Granite emplacement proceeded in two pulses: (i) Equigranular medium-grained biotite granite; (ii) Fine-porphyritic fine-grained leucogranite. Chemical features correspond to an A-type character of the granite. Rock is slightly peraluminous (ASI=1.05), rich in fluorine (about 0.5 wt% F), Rb (about 900-1200 ppm), Nb (60-80 ppm), Ta (10-15 ppm), Th (30-50 ppm), Zr (100-160 ppm), Y (74-157 ppm) and Be (5-19 ppm.), and poor in P (0.1 wt% P2O5). Both granite types contain phenocrysts of perthitic K-feldspar in groundmass composed of quartz, K-feldspar, albite and Li-bearing annite. Magmatic accessory phases comprise fluorite, magnetite, zircon, topaz, beryl, xenotime, monazite, thorite, cassiterite, and columbite. Chernovite, rhabdophane, bastnäsite, and Ce-dominated oxyfluoride are products of intensive hydrothermal alteration. The Th-U-total Pb age of monazite yielded the age of 308 +- 14 Ma.
- The Hora Svaté Kateřiny granite forms a small stock in the Krušné Hory / Erzgebirge Mts. Granite emplacement proceeded in two pulses: (i) Equigranular medium-grained biotite granite; (ii) Fine-porphyritic fine-grained leucogranite. Chemical features correspond to an A-type character of the granite. Rock is slightly peraluminous (ASI=1.05), rich in fluorine (about 0.5 wt% F), Rb (about 900-1200 ppm), Nb (60-80 ppm), Ta (10-15 ppm), Th (30-50 ppm), Zr (100-160 ppm), Y (74-157 ppm) and Be (5-19 ppm.), and poor in P (0.1 wt% P2O5). Both granite types contain phenocrysts of perthitic K-feldspar in groundmass composed of quartz, K-feldspar, albite and Li-bearing annite. Magmatic accessory phases comprise fluorite, magnetite, zircon, topaz, beryl, xenotime, monazite, thorite, cassiterite, and columbite. Chernovite, rhabdophane, bastnäsite, and Ce-dominated oxyfluoride are products of intensive hydrothermal alteration. The Th-U-total Pb age of monazite yielded the age of 308 +- 14 Ma. (en)
|