Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Determination of the Geometrical Configuration of Trajectory in Kan-Karaj Area(Central Alborz) using Multiple Inverse Method

Document Type : Original Research Paper

Authors
M. Eliassi 1
S. Ahmadian 2
1 School of Geology, University College of Science, University of Tehran
2 Research Institute for Earth Sciences, Geological Survey of Iran
10.22071/gsj.2009.57825
Abstract
Analysis of paleostress history in Kan_Karaj Area is the main object of this research. Paleostress phases were determined and categorized by numerous mesoscale faults containing slickenside lineations .The results were controlled and supported by some other geological features such as orientation of axial plane of folds, intrusion and stylolitic planes. The orientation of finite principal stress axes and geometrical shape of stress ellipsoid in a 4-D stress space were analyzed  by determination of rotational axis of each sub-area, according to Anderson Theory. Two different stress phases were separated and geometrical configuration of the maximum compressional stress  trajectory were illustrating on the structural map. The resulting trajectory shows north- south trend with an outstanding convergence to the north which reflects incremental intensity of stress in that direction during the fault system activities.
Keywords
Multiple inverse method
Stress trajectories
Reduced stress tensor
Central Alborz
Faulting
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Scientific Quarterly Journal of Geosciences
Volume 17, Issue 67
Winter 2008
Pages 140-149