Nd-Sr-Pb isotopes geochemistry of the Circum-Rhodope belt ophiolitic suites, Greece-Bulgaria: a synthesis

This study documents Nd-Sr-Pb isotopic compositions of the Jurassic Kassandra-Sithonia ophiolites and associated Jurassic Chortiatis arc suite of the western Circum-Rhodope Belt (CRB), which are compared with the same isotopes of the Jurassic arc-related Evros ophiolite of the eastern CRB in the northern Greece and southern Bulgaria. Nd-Sr-Pb isotopes are compatible with dominant mantle-derived Mid-Ocean Ridge Basalt (MORB) component mixed with a detectable amount of crustal material and/or sediment involved in their melt source in the subduction zone. These isotopic features are consistent with arc/back-arc origin of the Kassandra-Sithonia ophiolites and Chortiatis arc suite whose isotope systematics is comparable to Nd-Sr-Pb isotopes of the Evros ophiolite and the counterpart mafic rocks from the Mandritsa unit in the eastern CRB. Overall, the Nd-Sr-Pb isotopes systematics revealed mantle-crust interaction caused by mantle wedge magmatic process in the eastern Vardar zone-CRB Jurassic arc/back-arc systems.