[01] Ghasem Ghorbani Rostam, Department of Physics, Sciences Faculty, Islamshahr Branch, Islamic Azad University, Islamshahr, Iran. [02] Seyed Reza Sakhaei, Sama College, Islamic Azad University, Islamshahr Branch, Islamshahr, Iran. [03] Naser Ebadati, Department of Geology, Sciences Faculty, Islamshahr Branch, Islamic Azad University, Islamshahr, Iran.

We can be considered the Oman Line in the south of Iran as transition zone of two completely different seismotectonic zone, Makran subduction zone in the east and Zagross continental collision zone in the west. Studies of the stress and strain fields are very important in geodynamic analysis. So in this study, the stress and strain fields are considered in around of Oman Line to analyzing this region in terms of geodynamic. To achieve this purpose, amount of stress and their directions calculated by iterative joint inversion. From the east to the west of Oman Line, with transition from Makran to Zagross, the azimuth of maximum horizontal stress, reduced from 4.8° to 2.43°. In the previous studies, the direction of maximum stress is obtained N28° in the Arabian plate and N8° in the Iran. This amount in the world stress map approximated N31° for the Arabian plate. In this research direction of stress resulting from inversion obtained about N8° in the Zagross-Makran transition zone. It seems Zagross collision zone acts as a geodynamic boundary that changes the stress from N31° to N5°. Due to the direction of stress obtained in this study (about N5°) and trend of ZMP fault system (N160°), transpressional mechanism for ZMP is expected. Also mechanism of Sabzevaran-Jiroft -Kahnooj (SJK) fault system with an approximately north-south trending would be strike-slip mechanism. To surveying the strain field, considered the GPS data for finding the velocity vectors. Maximum difference between velocity vector and azimuth of maximum horizontal stress is obtaining 10 degrees in the BABS station, which it is in of transition zone. This cab is a reason for the existence of crushed zone in the Zagross-Makran transition zone. Also, in both sides of transition zone, the azimuth of velocity vector reduced from the west to the east.

Stress Field, Strain Field, Inversion of Focal Mechanism, Oman Line

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