The Ablah succession of Saudi Arabia (dating and geological significance)

The Ablah sedimentary succession represents a molasse basin in the Neo-Proterozoic Shield of Saudi Arabia. A rhyolite flow interbedded in the succession has been dated by the Pb/Pb method at 641± 1 Ma, indicating that the basin is a local expression of Panafrican tectonism in the south of the shield. Consequently, the Panafrican phase that has previously been described in the north can now be extrapolated to the south of the shield. This age determination also enables post-Panafrican events, which differ between the south and the north, to be analysed over the entire shield. (authors)