Origin of amphibolites within the Konya melange

Metamorphic unit, which is the main subject of this M.Sc. study, is observed as blocks together with serpentinized tectonites within the Hatip ophiolitic melange. The metamorphic unit is represented by amphibolitic rocks. Detailed petrographic studies show that amphibolite, epidote amphibolite, amphibolite schist, actinolite schist, garnet amphibole schist, plagioclase amphibole schist and epidote amphibole schist are the main metamorphic rock assemblages. Geochemical studies carried out on the metamorphic rocks show that these rocks were derived from tholeiitic and alkaline magma types. Trace and rare earth element contents of the tholeiitic and alkaline amphibolites are evaluated to be able to define mantle source characteristics. The alkaline amphibolites is similar to ocean island basalts (OIB), indicating that alkaline amphibolites were resulted from the metamorphism of OIB type basaltic rocks. The tholeiitic amphibolites exhibit close similarity to normal mid-ocean ridge basalts (N-MORB), enriched mid-ocean ridge basalts (E-MORB) and highly depleted mid-ocean ridge basalts. All the evidence show that the amphibolites in Çayırbağ-Hatip (Konya) region formed as a result of dynamothermal metamorphism of distinct basaltic magmatic rocks during intraoceanic thrusting within the evolution of the Neotethyan oceanic basin in Late Cretaceous. Key Wodrs: Neotethys, ophiolite, amphibolite, tholeiitic, alkaline.