Recent tectonics of East (Iranian) Azerbaijan from stress state reconstructions

Abstract

Abstract Iranian (East) Azerbaijan (E-Azerbaijan), in northwestern Iran, is characterized by relatively complex active tectonics. The area is shaped like a lozenge and is bordered by strike-slip faults. This region includes three fold and thrust belts, the Arasbaran, Ghoshe Dagh and Bozkosh mountain ranges, and includes a set of N–S trending compressive thrusts and folds and a set of E–W trending compressive structures. The stress inversion analysis and separation of stress tensors performed in this study indicate that the region is characterized by N–S to NE–SW (N018°) thrusting compression and NW–SE (N287° and N155°) strike-slip compression. The first stress system was responsible for the development of the three fold and thrust belts, while the second system formed the N–S striking structures, such as those in the Talesh, Salavat, Moro and Kiamaki Ranges. The stress reconstructions indicate that E-Azerbaijan is colliding with the South Caspian Basin and the Lesser Caucasus in the NE and N due to the compressive stress (S2) and with the Central Iranian Block and western Alborz in the southeast and east, respectively, due to the strike-slip stress mode (S3 and S1, respectively).