Orbicular monzodiorites from the NW part of the Plana pluton – preliminary results

Abstract

New for Bulgaria, orbicular rocks among monzodiorite from the NW part of the Plana pluton are presented. They comprise a central core of mafic segregation with gabbro composition (mainly of amphibole and plagioclase), surrounded by pyroxene and plagioclase-rich “shells” or rims, with the outer rim in sharp contact with the monzodiorite matrix.