Fracture systems of granites and Quaternary deposits of the area east of Aqaba: Indicators of reactivation and neotectonic activity

摘要

This study is based on measurement of hundreds of fractures (small faults, joints, cracks) in the crystalline rocks (Precambrian) and in Quaternary deposits of the investigated area east of Aqaba. Fault-slip data, joints, and any weakness zone data from the study area were collected from 20 stations. These stations represent wadi cliffs, stream channels, alluvial fans in the Pleistocene to Holocene sediments, and granitic rocks. During this study, it was assumed that any discontinuity in granitic rocks is a plane of weakness neoformed or inherited and reactivated during the successive tectonic phases. Whereas any cracks, joints, or small displacement in the Pleistocene and Holocene deposits are assumed to represent the activity or, more recently, deformation of the local area where they found. This study found the main trends of weakness zones, the kinematics, and the relation to main stress field in the region. Results show that the Late Neoproterozoic structures were reactivated during the Cenozoic and controlled the recent movement along the Dead Sea Rift. The NNE to N-S trend sets explain the reactivation of the late Neoproterozoic structures during Tertiary times. On the other hand, the formation of the Dead Sea Transform during the Miocene occurred along the N-S to NNE-SSW trending fault system, which was reactivated as sinistral fault.