Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)
Potassic and ultrapotassic rocks in the so-called Benešov-type granitoid body, Central Bohemian Plutonic Complex
Abstract
The so-called Benešov granodiorite body in the NE part of the Central Bohemian Plutonic Complex (CBPC) comprises several petrographically and geochemically distinct groups of granitoids accompanied with subordinate mafic rocks. Among them, ultrapotassic rocks occur being represented by small masses of mafic amphibole-biotite melasyenites and more widespread melagranites grading into more common potassic granites. Geochemical data suggest origin of these granitoids by hybridization of granitic magmas with mafic, mantle-derived ultrapotassic melts. Their occurrences fit into the zone of variable ultrapotassic plutonic rocks dominated by the durbachitic suite that is typical for the eastern marginal parts of the CBPC and for the Moldanubian Unit.
