Petrochemical comparison of redwitzites from the NW part of the Bohemian Massif

 

Pavla Kováříková, Emil Jelínek, Miroslav Štemprok, Václav Kachlík, František Holub, Vratislav Blecha

Geoscience Research Reports 38, 2005 (GRR for 2004), pages 103–106

Full text (PDF, 0.25 MB)

 

Abstract

Variscan redwitzites in the northwestern part of the Bohemian Massif are currently interpreted as igneous rocks formed by magma mixing between mafic (mantle-derived) and felsic (crustal) end members. We used Harker's and Bowen's diagrams to compare chemical compositions of redwitzites as well as to test various models of mixing. The geochemical testing reveals mafic gabbro (presumably olivine-bearing) as possible mafic end-member while the granite of the older suite granite (OIC) is the acid end-member. Various proportions of acid and mafic members explain the continuity of the Harker's diagrams, however, the fractional crystallization may account for some variations between mafic rocks of the redwitzite suite.