Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Edvín Pivec, Jiří K. Novák

The Mariánské Lázně granite: Petrology and geochemistry, western Bohemia

Journal of the Czech Geological Society, volume 41 (1996), issue 1-2, 15 - 22

The porphyritic, coarse- to medium-grained granitoids of the Mariánské Lázně body vary in composition from monzogranite to to quartz monzonite. New data on the chemistry of the main minerals, similar modal compositions and whole-rock analyses show correspondence to the Bor monzogranite. Both granitoids studied are medium fractionated with low to medium K/Rb (118-197 and 183-252, respectively), high Rb/Sr (1.16-1.36 and 0.87-1.85, respectively), and an increased Zr content. The proportion of TiO₂ and other „femic suite“ constituents in Haberland's dioritic facies (Haberlandt 1929) indicate some stage of assimilation of adjacent rocks rather than a fractionation trend. Considering these data, we suggest that the Mariánské Lázně granitoid body is not a part of the surrounding Karlovy Vary Pluton (Hejtman 1984), but a northern elongation of the Bor Massif.