Mylonitic gneisses of the Bulgarian and Greek Rhodope were deformed under medium pressure‐type metamorphism. The kinematic information contained in these gneisses shows that shear‐deformation occurred during development of a nappe complex. Lithologies and metamorphic histories allow a lower (footwall) and an upper (hanging wall) terrane to be distinguished that define a crustal‐scale duplex. As oceanic crust is involved, collision between two continental units with subsequent crustal thickening is inferred. The blocks would be Moesia to the north, and the Lower‐Rhodope promontory to the south, which collided in the Mesozoic to early Cenozoic. The nappe complex is characterized by south to southwestward (foreland directed) piling‐up and is associated with both coeval and subsequent extension. The late extension is associated with the establishment of a high temperature‐low pressure metamorphic gradient and plutonism that predates, but makes a transition to, the lithospheric extension of the Aegean Arc.

No abstract

The Strandja Massif (Sakar-Strandja Zone) forms an important link between the Balkan Zone (external Balkanides) of Bulgaria, which is commonly correlated with the Variscan orogen in Central Europe, and the Western Pontides of Turkey. The Bulgarian part of the massif is composed of a metamorphic basement (various granite gneisses, paragneisses, and schists) traditionally interpreted as having Precambrian age, Triassic-Jurassic metasedimentary cover, and Upper Cretaceous volcanosedimentary sequences. The basement is intruded by large granitic plutons of Variscan age that are widespread mostly across Turkish territory. New LA-ICP-MS data support the suggestion of Variscan granitoid magmatism in the studied area but do not confirm the presence of Precambrian rocks. Furthermore, two stages of magmatism are determined in relation to the Variscan metamorphism and deformation. The first one (301.9 ± 1.1 Ma) is represented by strongly deformed metagranites and thus is interpreted as syntectonic, while the second one is relatively younger (293.5 ± 1.7 Ma) and postmetamorphic.

No abstract

We report on the field occurrence and isotopic compositions of metamafic rocks exposed in the Serbo-Macedonian (Volvi and Therma bodies) and western Rhodope (Rila Mountains) massifs of Bulgaria and Greece. These metamafic units consist of high-and low-Ti gabbroic and basaltic rocks, whose Nd-Sr-Pb isotopes are compatible with mantlederived MORB and OIB components with a small amount of crustal material involved in their melt source. These isotopic features combined with the field observations are consistent with an intra-continental rift origin of the metamafic rocks protolith, and are comparable to those of the Triassic riftrelated mafic rocks in the northern Aegean region.