THE STRUCTURAL SETTING OF THE RED-SEA AXIAL VALLEY AND DEEPS - IMPLICATIONS FOR CRUSTAL THINNING PROCESSES

A lineamental analysis of the bathymetry in the nothern Red Sea axial valley, in conjunction with reflection seismic models, shows a poor geometric correlation between the axial valley and the Red Sea margins. However, there is good accordance with the lineamental patterns of the bordering continental plates. We conclude that the present axial tectonics of the nothern Red Sea is a rejuvenation of an inherited continental structure in a regime of weak distension. The distension appears distributed rather than focussed except at some points where the crust has been torn, or collapsed to form deeps. These areas have become starting points for limited crustal oceanization. Based on these conclusions, we discuss some models of crustal thinning with continental volume conservation. This process assumes a role for ascendant "decontinentalisation" of the basement.