RODINGITES OF THE EASTERN PART OF THE JORDANÓW - GOGO ÓW SERPENTINITE MASSIF, LOWER SILESIA, POLAND

ELZBIETA DUBINSKA
Institute of Geochemistry, Mineralogy and Petrography, Faculty of Geology, Warsaw University, al. wirki i Wigury 93, 02-089 Warsaw, Poland

Abstract

Rodingites from the Jordanów-Gogo ów massif (Lower Silesia, southwestern Poland) formed from two types of protolith, mafic rocks and albitites or plagiogranites. The formation of Ca- silicates predates that of the CaMg-silicates. The formation of the Ca-silicates is probably related to low-temperature ocean- floor metamorphism, whereas the CaMg-silicates seem to be products of younger greenschist-facies continental metamorphism (possibly of Variscan age). Calc-silicate rocks from the "leucocratic zone" at Jordanów are unusual metarodingites, since their formation included rodingitization of plagiogranite, thermal metamorphism or metasomatism of an apophysis of Variscan granite, several episodes of brittle deformation involving cementation of older rocks by newly formed minerals, and late Variscan as well as post-Variscan alteration.

Keywords: rodingite, ophiolite, ocean-floor metamorphism, continental metamorphism, eastern Sudetes, Poland.