Magmatic epidote from gabbro

Epidote is traditionally considered a mineral indicating metamorphic and metasomatic genesis of rocks. Recently, the magmatic nature of epidote of many granitoid intrusions has been proved. We present the first data on the magmatic origin of epidote, which is one of the rock-forming minerals of anorthite fassaite and biotite-amphibole gabbros. These rocks form block inclusions in the serpentinite melange plate localized in gneisses of the Proterozoic Selyankino strata of the Il'meny Mountains complex in the South Urals. The holocrystalline structure and cenotypal appearance of the epidote gabbros, their gabbro, porphyritic, and ophitic textures, the induction surfaces of synchronous growth between the hosted minerals, the mineral crystal faceting, and high-temperature paragenesis evidence the magmatic origin of the rocks. (c) 2008, IGM, Siberian Branch of the RAS. Published by Elsevier B. V. All rights reserved.