Tectonic evolution of the gulf of Aqaba-Dead Sea transform fault system

Abstract

Neogene tectonic phases related to stresses which created the Gulf of Aqaba-Dead Sea transform fault system were recorded from evidence in the central part of the Wadi Araba. The chronological sequence of deformation stages is as follows: 1. (1) Epeirogeny (latest late Eocene-Oligocene). 2. (2) Faulting and warping (?Oligocene-Middle Miocene). 3. (3) Folding striking between north-northeast and northeast, E-W trending and N-S shear faulting, and NW-SE normal faulting (Miocene). 4. (4) Uplift and faulting (Pliocene-Pleistocene). 5. (5) Faulting with volcanic activity (Pleistocene). 6. (6) Sinistral movement along the major shear fault in the Wadi Araba. Indications are that this phase is still active (Pleistocene-Recent). The re-strain phases recognised are clues for the investigated area and the entire region to the understanding of the tectonic evolution of the Gulf of Aqaba-Dead Sea transform. Structural features contributing to evidence of strike-slip movement are: drag folds, reverse and normal flower structures, alternation of the downthrown side along the fault trace, gently waved vertical fault planes, horizontal slickensides, transpressive and transtensional pressure ridges and rhombs, linear fault traces without marked vertical throw, and fault plane ridges. A sinistral offset of 40 km along the N-S Al Quweira Fault was deduced from the displacement of distinctive andesitic rocks found on both sides of the fault. For the E-W Salawan Fault, a dextral movement of at least 7 km was determined from the offset of formation boundaries. North-northeast-striking deformed belts containing monoclinal to recumbent en-echelon folds can be seen in the Gulf of Aqaba-Dead Sea transform fault zone. The axial planes of the folds dip southeast and face northwest. These structural elements indicate local SE-NW compressional stress.