Schematic geography of the major rivers systems in northern and western Africa during the Late Cretaceous (modified from Zellouf and Delfaud 1986, Delfaud 1986, Dutheil 2000). A Kem Kem river system with flow to the north B Kem Kem, paleo-Nile and paleo-Niger river systems. Abbreviations: 1 Meseta 2 Anti-Atlas 3 Ougarta 4 Kem Kem river and delta 5 Paleo-Nile river and delta 6 Paleo-Niger river and delta.