Document Type : Original Research Paper

Author

Assistant Professor, Department of Geology, Natural Sciences College, Tabriz University, Tabtiz, Iran

Abstract

Iranian Azerbaijan is a region in Northwest of Iran where has large active deformation and seismicity. It is located between two orogeny, Zagros in the south and Lesser Caucasus in the north. In this research geological structures and tectonic stress state of area are studied to search connection the tectonic and neotectonic of Azerbaijan. In this study the analytical method of Angelir, 2002, is used to analising the stress tensors. Also his methods, 1984 and 2004, are used to separation of stresses. Firstly it is collected seismic and field data of faults and analyzing their stress states. Then 2nd order stress field of Azarbaijan microplate is reconstructed by stress separation analysis. Also remote sensing methods helps to study of imbricate structures in the northern and southern parts of Azarbaijan microplate. The stress analysis results in this study (by analytical method, for seismic and field data) shown there are two compressional stresses (NE-SW and NW-SE directions). First stress system by NE-SW directions cause developing of three tectonic grains as Arasbaran, Ahar (Goshe Dagh) and Bozkosh fold thrust belts. But the second one (NE-SE direction stress system) cause developing of thrusts in N-S direction. Reconstruction of first order stress in relation with the tectonic grains, and structures, reduced the tectonic model of Azerbaijan plateau. In this model the (East) Azerbaijan plateau is in collision with Lesser Caucasus in north, South Caspian basin in east, and Central Iranian block in south and west. In this way reconstructed compression induced the conter-clock wise rotation to the Azerbaijan plateau.

Keywords

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