Structural Analysis of the Western Part of Shotori Mountain Range; Eastern Iran

Document Type : Research Article

Authors

1 Ph.D. Candidate, Department of Geology, Faculty of Earth Science, University of Birjand, Birjand, Iran

2 Associate Professor, Department of Earthquake Research, Shahid Bahonar University of Kerman, Kerman, and International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran

3 Associate Professor, Department of Geology, Faculty of Earth Science, University of Birjand, Birjand, Iran

4 Associate Professor, Department of Geology, Shahid Bahonar University of Kerman, Kerman, Iran

5 Professor, Department of Geology, Shahid Bahonar University of Kerman, Kerman, Iran

6 Associate Professor, Department of Earth Sciences, Utrecht University, Utrecht, Netherlands

Abstract

NW-SE trending Shotori range has some structural elements such as folds and fractures (including thrust and strike-slip faults), following almost a similar trend. Based on the plotted stereograms, the predominant mechanism of the region’s faults is thrust with a dextral strike slip component which implies overcoming compressive stresses in the region. On the other hand the strike-slip horizontal component of the faults may also be due to the Nayband fault activities on Shotori and Esfandiar thrust zones. The steep dip of these faults may also be due to some normal faults converted to reverse faults as a result of stress phase change from tensional to compressional. Based on planar axis perpendicular compression or stretching axis σ1= 34, 10 and σ3= 296, 38 were obtained for the study area. striogram axial surface folds  dominantly show  NW-SE direction, which is indicates  compression axis which is equal N53, 12.Aeromagnetic data analysis revealed two magnetic lineaments with the same trends as surveyed lineaments in the field. The relatively high magnetic intensity of these lineaments could be due to basement faults in the region. With regards to obtained stereo plots, trend of the folds’ axis are parallel to the regional thrust faults and folds’ contour diagrams apply asymmetric folds with faulting in the area.

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References

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Journal of Seismology and Earthquake Engineering
Volume 24, 1&2
January 2022
Pages 27-37

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