Structural evidence of tear faults in Kamarmahdi anticline, Tabas block, Iran

Many examples of tear faults are observed in Tabas block. These faults are usually seen in belts with active folds. In this research, an example of the mentioned faults has been studied. The axis of the Kamarmahdi anticline has a north-south trend. In the north of Kamarmehdi anticline, there is a fault with an approximate trend of N75E which does not have a clear shear sense on the ground, and the geological structures on both sides of this fault are also different. This research has been done to determine the shear direction of the said fault. For determining the shear sense of this fault, a geological map with a scale of 1:1000, was prepared and the boundary of the rock units and the folding axis are taken as a guide to calculate the fault shear direction. The amount of heave (143m) and throw (331m) of fault was determined after preparing the geological cross sections on both sides of the tear fault, using AutoCAD software. By determining the movement direction of the fault, the existence of the tear fault and its displacement has been proven, and the movement pattern of the formation of the tear fault has been presented.