Lithology and planktic foraminifera biostratigraphy of Aptian–Albian boundary as encountered in Jebel Sidi Salem (northeastern Tunisia)

The Aptian–Albian boundary has long been difficult to identify along the foreland basin of the Tunisian Atlas, although ammonites occur in the Fahden Formation. The revision of Aptian–Albian series from Jebel Sidi Salem, in the northeastern part of the Tunisian Ridge, provides new data for the recognition of this boundary. The Jebel Sidi Salem section contains a rich succession of planktic foraminifers’ index species which document a complete marine record of Aptian–Albian boundary with no sign of redeposition. Six zones of planktic foraminifera have been identified through the late Aptian to middle Albian; including Globigerinelloides algerianus Zone, Hedbergella trocoidea Zone, Planomalina cheniourensis Zone, Paraticinella eubejaouensis/Ticinella roberti Zone, Hedbergella planispira Zone and Ticinella primula Zone.