First, a thermal anomaly developed in the mantle in the earliest stages of rifting, causing the rise of the asthenosphere and the thinning of the subcrustal continental lithosphere.
This was followed by decompressions, which occurred due to uplift related to the gradual stretching and thinning of the crust as rifting continued.
As the basaltic injections become restricted to a narrow axial zone, true seafloor spreading initiates with the Vine-Matthews-type magnetic anomaly stripes.
While there is a general agreement that the axial trough of the Red Sea originated by seafloor spreading, and therefore is underlain by oceanic crust, the nature of the crust beneath the main trough and coastal plains of the Red Sea is still controversial, leading to the development of a few theories.
All geophysical data from the axial trough reveal seismic velocities typical for oceanic crust.
[5] The rift zone includes the island of Jabal al-Tair, formed by the basaltic stratovolcano of the same name, located northwest of the Bab al-Mandab passage at the mouth of the Red Sea, about halfway between Yemen and Eritrea.