Document Type : Original Research Paper

Authors

1 M. Sc. Student, Department of Geology, Tarbiat Modares University, Tehran, Iran

2 Associate Professor, Department of Geology, Tarbiat Modares University, Tehran, Iran

3 M.Sc., Exploration Directorate, National Iranian Oil Co., Tehran, Iran

Abstract

The NW-SW trending Garmsar Anticline is located in the Abardej area in northwestern part of the Garmsar city, 110 km east of the Tehran province. The aim of this paper is to investigate folding style of the Garmsar Anticline and its relationship with the Kavir thrust and also the influence of tectonic regime inversion on the structures of the study area. Furthermore, the study aims at determining spatial development of the structures based on field observations and subsurface data interpretation. The presence of a thrust fault along the southern limb of the Garmsar anticline suggests that this anticline is a fault-related fold, whose specifications are characteristic of faulted-detachment folding style. The existence of the Lower Red Formation evaporates as a ductile horizon has influenced folding style in the Garmsar Anticline, which is clearly observed in seismic lines. The anticline axis is also cross-cut by secondary strike-slip faults that are the youngest structures in the area. Fold amplifications during compressional regime has resulted in development of this set of strike-slip faults across the axis of the Garmsar Anticline.

Keywords

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