The Fariman Complex in northeastern Iran plays an important role in deciphering the geodynamic evolution of Palaeotethys and the Cimmerian orogeny in Central Asia. The Late Permian to Triassic rocks of the Fariman area consists of mafic to ultramafic cumulate rocks, pillow basalts, turbidite succession, limestones, and metapelites. Our detailed structural analysis demonstrates two deformation phases. The earliest deformation (D1), a synmetamorphic progressive deformation which occurred in brittle-ductile conditions, is characterized by pervasive foliation, reverse and thrust faults, refolded folds, and amphibolite facies metamorphism. The thrust sheets have Permian allochthonous masses emplaced in the highlands of the Fariman Mountains. The D2 deformation is represented by dextral strike-slip faults, which affected the region after a period of sedimentation and erosion. Our fault-slip data demonstrates recent slip sense inversion from reverse dip-slip to dextral strike-slip in response to the D2 tectonic event. From the geodynamic point of view, the convergence between the Iran and Turan plates during the Early Cimmerian event generating a progressive deformation (D1) and metamorphism of Triassic and older rocks. In Late Cenozoic times, the tectonic regime change resulted in the dextral tectonic regime activity (D2), which affected the pre–existing structures. Combined with other published data, we conclude that the Fariman Complex as a fragment of an oceanic plateau, which was accreted in the Paleotethys suture zone.

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