Abstract
Ajjaj-Qazaz-Hanabiq shear zones (AQH-SZ) are ductile to semi-ductile shear zones that are located within the Midyan terrane in the northwestern part of the Arabian Shield. They expose Neoproterozoic rock assemblages that comprise an elongated ridge of ophiolitic rocks, arc-metavolcanics, and contemporary arc-related intrusions. They are unconformably overlain by the post-amalgamation molasses-type sediments and finally intruded by late- to post-tectonic intrusions. The strain analysis results of the AQH-SZ are consistent with no significant differences. The average of R-sXZ values in the three shears ranges from 2 to 2.22, while the R-sYZ average ranges from 1.7 to 1.9. The average of stretching in the three shears ranges from 34 to 42%, while the shortening ranges from 33 to 37%. The stretching direction is oriented parallel to the shear trends; WNW directions in the Ajjaj and Qazaz shear zones, and NNE direction in the Hanabiq shear zone. The change in direction of stretching is suggested to be due to the exhumation of gneissic cores which also might have caused the presence of a local dextral sense in Hanabiq shear zone. Based on the similarity in the strain analysis results and the absence of overprinting relationships at the conjunction areas of the three shears, it is concluded that the three shears are one major shear.