The Jurassic ophiolite complex of the Dinarides consists predominantly of graywackes, shales, and cherts, in which are included large massifs of lherzolite with subordinate gabbro, diabase, spilite, and amphibolite. Contacts between peridotite massifs and adjacent rocks are for the most part tectonic. However, metamorphosed country rocks with primary intrusive relations are preserved in many places around larger ultramafic massifs. Two main groups of metamorphosed rocks can be distinguished:

  1. High-grade amphibolite and eclogite occur in relict zoned aureoles around the larger ultramafic bodies, and suggest metamorphism in the upper mantle. The zonation is best shown by variation of both plagioclase and amphibole composition; amphibole is mostly pargasite with variation in Mg and Fe, and the plagioclase composition varies from anorthite to oligoclase.

  2. Low-grade amphibolite with greenschist occurs in narrow zones along the borders of diabase masses adjacent to large ultramafic massifs. The changes from diabase to low-grade amphibolite are in some places gradational. The mineral assemblages include al-bite-oligoclase, tremolite-actinolite or green hornblende, chlorite, epidote, and relict clinopyroxene.

P,T-stabilities of the all mineral parageneses are discussed in detail and correlated with the data of experimental petrology. The genesis and the evolution of the Dinaridic peridotites are interpreted in terms of plate tectonics.

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