Late Cenomanian–Early Turonian ammonites of the southern Tethys margin from Morocco to Oman: Biostratigraphy, paleobiogeography and morphology

摘要: Abstract The Cenomanian–Turonian ammonite biostratigraphical framework for the southern Tethys margin (North Africa, Middle East and Arabian Peninsula) is becoming better understood. A first attempt at a synthetic range chart presented, with 85 taxa precise correlations ammonites along west–east transect from Morocco to Oman, inclusive of Trans-Saharan Seaway as far south northern Nigeria. On basis critical review taxonomy, 13 bioevents can be identified in interval Late Cenomanian Early Turonian (c. 3.5 myr) each bioevent corresponding time approximately 270,000 years, on average. They are consistent throughout several regions margin, though some gaps remain, least stage boundary. These correlated zonation defined stratotype (GSSP) base Western Interior (USA). paleobiogeographic distribution reveals endemism but predominant picture that homogeneous fauna area, even distinct Boreal (Atlantic domain) marine influences evident. An interpretation evolution conch morphology ornamentation through zones Cenomanian–Early proposed.