Tectonics
Sepideh Rezabeyk; Abdollah Saidi; Mehran Arian; Ali Sorbi
Abstract
In the Northern part of Suture Zone (Kermanshah) the deep sea sediments, oceanic crust remnants, platform carbonates, igneous and metamorphosed rock of active margin and carbonate sequence of passive margin are assembled in this studied area. This convergent area has provided a very complicated structural ...
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In the Northern part of Suture Zone (Kermanshah) the deep sea sediments, oceanic crust remnants, platform carbonates, igneous and metamorphosed rock of active margin and carbonate sequence of passive margin are assembled in this studied area. This convergent area has provided a very complicated structural zone. The main purpose of this study is stress characteristic analysis. A great data has gathered from the faults which are appeared within the rocks specially the radiolaritic rocks. The data includes characteristics of fault surface geometry, fault slip and lineation slip related. By using the method Right Dihedral, the position of main stress was obtained. The great number of reverse faults have a NW- SW trend, while the strike- slip faults, show a NE- SW direction. The Normal faults with a different displacements appeared younger than the other faults. The result of this study that we obtained the situation of main stress σ1, σ2 and σ3 respectively is 059, 305 and 195.
R Sadeghi; A Saidi; M Arian; M Ghorashii
Abstract
In this study, separation of paleostress phases in the Khalkhal region has been doneusing paleostress analysis based on heterogeneous fault slip data and related slip lineations.The data have been measured and collected from the Jurassic, Cretaceous and Eocene units.To determine the sense of shear or ...
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In this study, separation of paleostress phases in the Khalkhal region has been doneusing paleostress analysis based on heterogeneous fault slip data and related slip lineations.The data have been measured and collected from the Jurassic, Cretaceous and Eocene units.To determine the sense of shear or slip, indices such as stratigraphic separation across the faults, kinematic indicators on fault surfaces, conjugate fractures, and tensile cracks were used.The data were analyzed with the help of inversion method. The results indicate that strike-slip regime is dominant in the region. Constraining the stress phases and comparison with the field and seismic data revealed that the third stress regime is characterized by avertical σ2and a NE-SW extension related to the modern stress regime, which is also compatible with the seismic data. The first and second phases of stress prevailed along NW-SE and N-S directions related to the paleostress regimes.Various investigations, including rose diagram analysis of faults and arrangement of structures show that the faults in the region are dominantly strike-slip and strike-slip with normal component, and the shape of the stress field in the region is prolate.
