Syrian Arc
The Syrian Arc is a series of
Extent
The furthest west that folds have been attributed to the Syrian Arc deformation phase is in the northern Western Desert near
Geometry
The Syrian Arc has an overall S-shape, with structures trending WSW–ENE in Egypt and Syria and SSW–NNE trending in the intervening section.[2]
The Palmyra fold belt
In Syria the main Syrian Arc structure is the WSW–ENE trending Palmyra fold belt. It extends eastward from the Dead Sea Transform, dying out near the Euphrates Graben. The left lateral offset of the Palmyrides against the other part of the Syrian Arc across the Dead Sea Transform has been estimated as a maximum of about 107 km.[3]
Origin
Two main phases of tectonics were responsible for the formation of the Syrian Arc structures. The first, dominated by extensional tectonics, was associated with the development of a passive margin in northern Africa as the Neotethys Ocean was formed. The second, dominated by contractional tectonics, was associated with the closure of that ocean. Some of the structures were further modified in the Cenozoic during the formation of the Dead Sea Transform and the continued northward movement of the Arabian Plate.[2]
Passive margin formation
During the
Neotethys closure
As part of the overall convergence between the African and Eurasian plates, the Neotethys ocean began to close. This led to a change in the prevailing stress field in the passive margin to one of regional compression, NNW–SSE orientated.[2] This caused reactivation of many of the extensional faults bounding the half-graben basins, inverting them. The first phase of inversion folding appears to have started in the Santonian age.[4] Several further pulses of folding occurred during the Paleogene in the Western Desert.[5]
References
- .
- ^ a b c d El-Motaal, E.A.; Kusky, E. (2003). "Tectonic evolution of the intraplate S-shaped Syrian Arc Fold-thrust Belt of the Middle East Region in the context of Plate Tectonics". 3rd International Conference on the Geology of Africa. pp. 139–157.
- S2CID 129801419.
- . Retrieved 15 May 2010.
- S2CID 133638327.