Unexpected Geodynamical Perspective Of The Sinai Areay Gps

Résumé: This paper shows the results obtained by the joint analysis of a local GPS network of IH sites, from the Suez Gulf to the Si nai peninsula, and a regional network of 4 permanent GPS stations, from Israel to Cyprus. The analysis of two repeated surveys shows significant displacements at the Sinai sites and Cyprus. A rough estimation of the mean relative velocities gives fo r the Sinai peninsula and Cyprus the highest values of the network with about 3.0 cm/y and 2.4 cm/y respectively. Velocity decreases at about 60% of its value (1.4 -1.8 cm/y) along the Dead Sea - Jordan transform fault. The relative velocity pattern indicates the presence of active creeping along the southernmost part of the Aqaba fault system, while the Dead Sea-Jordan segment, showing insignificant displacements, could be locked. Th e relative displacements detected across the Gulf of Suez area shows a significant compressional component. This geodynamical picture leads to two possible interpretations: the first is that the opening motion of the Gulf of Suez has been entirely transfe rred on the strike-slip motion of the Aqaba-Levant transform fault; the second is that origins exclusively as post-seismic effect. In this context, other GPS surveys are required to really understand the geodynamical style of the Sinai peninsula.

Publié dans la revue: Bulletin des sciences géographiques de l'INCT