Petrology, Geochemistry and Radioactivity of Durbachites from Třebíč Massif Along the Třebíč FaultArticle PDF
Petrology, Geochemistry and Radioactivity of Durbachites from Třebíč Massif Along the Třebíč Fault
Coarse grained, fine grained durbachites, alterated durbachites and mafic xenoliths were distinguished in the w.-e. profile across the Třebíč batholith. The most remarkable geochemical features are the high concentration of K2O (5.2-6.5%), MgO (3.3-10.4%), Ba (1069-2630 ppm), Cr (198-630 ppm), Ni (63-289 ppm), Zr (174-476 ppm), and low concentration of Na20 (1.3-2.5%). The replacement of plagioclase by K-feldspar and amphibole by biotite are typical features for all rock types. The primary mineralogy and geochemistry of durbachitic rocks and also mafic xenolith were probably affected by replacement processes in the late stages of the crystallization. Durbachites display considerable variation in the concentration of U (5.5-32.1 ppm) and Th (11.2-74.8 ppm).
Kateřina Zachovalová, Jaromír Leichmann, Dept. of Geology and Paleontology, Masaryk University, Kotlářská 2, 611 37 Brno, Czech republic
Jindřich Štelcl, Dept, of Mineralogy, Petrography and Geochemistry, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic