Kinematic and dynamic analysis of North-Tehran tectonic wedge formed in south central Alborz, Iran

摘要

To answer the question “Whether the North-Tehran tectonic wedge is a dynamic tectonic wedge or not?” we applied paleostress techniques to investigate fault slip data. The mean reduced stress tensor is defined for all stabilized stress regions. Unscaled Mohr’s circles drawn for fault slip data were used to obtain the relative slip tendency of clusters on diagrams. It showed that the slip tendency in the vicinity of fault junction is much lower than expected. The meanσ1 defined for a combination of fault slip data trends N14°E nearly parallel with the overall pressure in Iranian crust at the latitude of Central Alborz. This trend suggests the least effect of boundary faults and the wedge between them on stress orientations inside the wedge. Finally, the stress trajectory map was prepared showing the configuration and relative intensity of σ1. The map did not illustrate any convergence in σ1 trajectories and the consequent concentration of stress and seismic potential in fault junction. That is a direct evidence for disagreeing the dynamicity of this tectonic wedge.