Mineralogical-Petrographical Record of Melt-Rock Interaction and P–T Estimates from the Ozren Massif Ophiolites (Bosnia and Herzegovina)

The Dinaride Ophiolite Belt formed from the Jurassic part of Neotethys. investigated Ozren ophiolite complex in Bosnia and Herzegovina consists peridotites, plagioclase plagiogranites, troctolites other gabbroic rocks, fewer basalts. Lherzolites harzburgites contain corroded ortho- clinopyroxene1 porphyroclasts enclosed olivine matrix. boundaries between aggregates pyroxene1 spinel1 are infilled by medium-grained undeformed clinopyroxene2, less orthopyroxene2, spinel2, often clinopyroxene3-spinel3 symplectites. These textures indicate final crystallization peridotite subsolidus conditions. Partial dissolution deformed coarse-grained most likely occurred due to their reaction with rest melt present grain boundaries. Al decrease pyroxene2 3, or Cr increase spinel2 3 is characteristic. Peridotites associated inferred remnants a gabbro-dolerite layer, whereas basalts radiolarites occur as rare dm-size fragments an ophiolitic breccia. Troctolites display interstitial plagioclase, clinopyroxene, Na-Ti-rich amphiboles, phlogopite olivine-spinel matrix, indicating replacive character impregnating within dunite layers. Clinopyroxene-plagioclase-ilmenite-±amphibole basaltic dykes peridotites subridge extension, mantle thinning, deeper melting. Iron-enriched olivines peridotite-dyke interfaces troctolites. Hydrated ultramafics mafics biotite, phlogopite, clinozoisite, epidote, chlorite aggregates. Estimated magmatic T two-pyroxene thermometry 1000–850 °C, for spinel facies. Ca-in-orthopyroxene1 provided 1028–1068 Ca-in-orthopyroxene2 gave 909–961 °C at estimated P 1.1–0.9 GPa. However, dyke was constrained 1200–1100 0.45–0.15 GPa single clinopyroxene thermobarometry. obtained P–T conditions environment formation than crosscutting dykes. thrust-sheet hanging wall obduction-related accretionary wedge were amphibolites 620 0.85 Ti-in-amphibole amphibole-plagioclase 300 0.5 determined exhumation shear zone using combination Si-in-phengite barometry.