Low temperature Thermochronometry and Structural constrains on evolution pattern of the Bozgoosh and Chehel-Nour Mountains intersection, NW Iran

Located at the Arabia-Eurasia collision zone, the E-W trending Bozgoosh Mountain aligned perpendicularly to N-S trending Chehel-Nour Mountain in the northwest of the Iranian Plateau. There is not any thermochronometry study has been performed to determine the initial time of their uplift and exhumation. Our low-temperature Thermochronometry analysis in the apatite U-Th/He (AHe) system in combined with previously unpublished data set at central Bozghush Mountains and structural data show that the onset of the Late Cenozoic uplift and exhumation of the Bozgoosh Mountain (~19-25 Ma) is a bit older than Chehel-Nour - Gaflankuh Mountain (~15 Ma). It seems that deformation of the Bozgoosh Mountains started at with respect to middle Miocene unset time of deformation at Chehl-Nour and Gaflankuh Mountain. Then it can be concluded that these two perpendicular maountain ranges have not been formed in a single phase of partitioned deformation. On the other hand N-S trending Chehel-Nour and Ghaflankuh Mountains have similarly deformedsynchronous with the N-S trending part of the southern Talesh Mountains in its eastern border. Our results have also document that the Bozgoosh and Chehl-Nour mountains intersection is actually a part of Bozgoosh mountain.