Late Cenozoic Faulting at Ziar Area in Central Alborz

Document Type : Research Paper

Authors

Department of Geology, Tarbiat Modares University, P. O. Box: 14115-175, Tehran, Iran

Abstract

Field investigation and structural mapping of faults cut Mezozoic to Late Cenozoic (PlioceneQuaternary) rocks in Ziar area of Central Alborz have led to identification of the NW- and NE- trending
fault sets. Slickenlines, fault steps and riedel shear fractures are mainly applied as kinematic indicators
for analysis of the faults mechanisms. The NW-trending reverse faults with left-lateral strike-slip
kinematics and positive flower structure geometry (such as Golezard Fault) is the first set. This set cut
through all rock formations up to Plio-Quaternary are proposed to develop during the northeastern
oblique transpression deformation governs the Alborz during the final collision of the Arabian- Eurasian
plates in Late Cenozoic (Pliocene). The NE-trending strike-slip faults with normal kinematics that crosscut the Damavand Quaternary volcanic rocks as well as the first faults set are the youngest faults in the
region. This fault set development have attributed to the northwestern movement of the South Caspian
block in Quaternary, which led to an extension in Central Alborz. These young faults mapped for the
first time in this work constrain the Late Cenozoic (Quaternary) faulting of Central Alborz zone, referred
as a result of the range major faults reactivation, previously. 

Keywords

Main Subjects


Article Title [Persian]

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