Neogene block rotation in central Iran: Evidence from paleomagnetic data

Paleomagnetic results from Oligocene– Miocene sedimentary units in central Iran are used to reconstruct the history of Neogene tectonic deformation of this region. Paleo magnetic data show that in central Iran, crustal blocks bounded by sets of rikeslip faults are rotated to accommodate NNESSW shortening related to Arabia-Eurasia convergence. Counterclockwise rotations of 20°–35° have been measured in the Tabas and Anarak areas, south of the Great Kavir fault, characterized by the presence of N-S to NNW-SSE right-lateral strike-slip faults. Conversely, in the Great Kavir and Torud areas, where ENE-WSW left-lateral strikeslip faults have been recognized, paleomagnetic results are less conclusive because the small amount of measured clockwise rotation shows a statistical uncertainty, which also includes the possibility of no rotation. Some of these faults have been active during the Quaternary up to present day, suggesting the possibility that block rotation is still occurring in central Iran.