Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Dynamic Analysis of Fractures in North of Torud – Moalleman Area (Central Iran, East South of Damghan)

Document Type : Original Research Paper

Authors
A. Keynezhad 1
M. Pourkermani 2
M. Arian 1
A. Saeedi 3
M. Lotfi 3
1 Faculty of Basic Sciences, Islamic Azad University, Research and Science Campus, Tehran, Iran
2 Islamic Azad University, North Tehran Branch, Tehran, Iran
3 Research Institute of Earth Sciences, Geological Survey of Iran, Tehran, Iran
10.22071/gsj.2010.54577
Abstract
Detailed geological and structural analysis of north of Torud-Moalleman area (Central Iran), between Anjilu fault in north and Torud fault in the south, led to tectonic elements of this limit such as fractures and relative of their mechanism with left lateral sheared zone of two main faults. This study provides a movement system of Chalu, Gandi and Hafez faults in this shear zone. On the basis of kinematics findings and using general methods of fault slip analysis (orientation of slip plane, slip vector, shape of stress ellipsoid and angle of internal friction) region stress field were calculated after determining the angle of internal friction for each one of fault limits. Then, the main stress orientation determinates for combination data that values of ،وwere 195/10, 339/78 and 104/07 respectively. The shape of stress ellipsoid was defined on the basis of shape factor, [R= (-) / (-)], (Angelier, 1975). The R-value for whole studied regions was about 0.5 and deformation type was mainly left lateral transpressional with reverse component. Such results are evident from N-NE (N195) trending  in the region and northward movement of the lithosphere. These finding are in line with field research results of fractures, faults and mechanism in this general shear zone.
Keywords
fracture
Dynamic analysis
Torud
Stress
Central Iran
Moalleman
References
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Scientific Quarterly Journal of Geosciences
Volume 20, Issue 78
Autumn 2011
Pages 3-16