Post-Messinian evolution of the Florence Rise area (Western Cyprus Arc) Part II: Experimental modeling

The Florence rise is located southwest of the island of Cyprus and belongs to the western part of the Cyprus arc. The Florence rise is an accretionary prism, with some amount of strike slip, where the thick layer of evaporitic Messinian decouples deformation in the post-Messinian cover from that in the pre-Messinian “basement.” The basement structural highs, whether presently active or inactive, influence the deformation and displacement patterns of the salt and its overburden.Our first experiment focused on the presence, in nature, of normal faults located above basement thrusts. Deformation of the salt layer and its overburden was influenced by several processes. On one hand, the entire model was subjected to regional shortening, and basement thrusts formed. On the other hand, the local vertical rise associated with basement thrusts created local slopes down which the salt and overburden glided gravitationally, in some places leading to the formation of normal faults in an otherwise compressional regional setting.Our second experiment was designed to model the buttressing effect of the Florence rise and the Eratosthenes Seamount on thin-skinned displacement patterns during regional gravity spreading of the Nile cone. Results indicate that in the Northeastern distal region, buttressing by these two basement highs forced the salt and its overburden to flow northeastward, as a lateral escape toward the free boundary of the region.

► Models show how deep-seated and salt tectonics interact in a accretionary prism.
► Thrusting creates basement slope, thus causing local thin-skinned gravity gliding.
► Gravity gliding allows formation of grabens locally, despite regional shortening.
► Passive buttress reoriented spreading direction of the Nile deep-sea fan.
► Passive buttress generated salt/overburden lateral escape in the Florence rise area.