Palynology of Cretaceous/Tertiary Boundary Sediments in West Africa

An estimated 60 to 80 percent of all living species were affected by the Cretaceous/Tertiary (K/T) boundary mass extinction event, which continues to be studied in great detail in order to understand its overall effects. Although several mid to high latitude studies have yielded information on regional paleofloral response to this event (e.g., the fern spike), very few similar low latitude studies have been undertaken. Seventy-seven samples from the ALO-1 well in the Anambra Basin, Nigeria and Ocean Drilling Program (ODP) Hole 959D in the Côte d'Ivoire-Ghana Transform Margin provide information on the response of tropical paleofloras to this extinction event. The ALO-1 K/T sediments are from the Nsukka (Upper Maastrichtian – Lower Paleocene) and Imo (Paleocene) formations and represent dominantly clastic deposition in prodeltaic and shallow marine environments, respectively. In the ODP Hole 959D this interval consists of black claystone deposited in a bathyal environment. Statistical techniques (cluster analysis, range through, rarefaction) yield palynological data for interpreting biodiversity patterns in these study areas. Comparisons of pollen and spore records in these sediments to tropical South American data help with evaluating the similarities and differences between the two regions during this time period. Preliminary data suggests that during the Paleocene similar genera such as Proxapertites, Longapertites, Mauritiidites, Echitriporites, and Spinizonocolpites were present in both areas. -->