Planktic foraminiferal turnover and δ13C isotopes across the Paleocene-Eocene transition at Caravaca and Zumaya, Spain
Abstract Biostratigraphic and faunal analysis of planktic foraminifera and benthic foraminiferal isotopes at Zumaya and Caravaca sections in Spain indicate that Zumaya has a continuous record with high sediment accumulation rates across the Paleocene-Eocene transition whereas Caravaca has a hiatus with the uppermost Zone P4, Zone P5 and the lower part of Zone P6 missing. Both sections contain nearly continuous and expanded records of the global δ13C excursion at Zumaya and Caravaca respectively. The δ13C excursion is associated with dark grey shale deposition in a dysaerobic benthic environment. This δ13C event is associated with a major planktic foraminiferal turnover marked by the gradual extinction and evolution of 33% and 18% of the species respectively. A rapid change in the relative abundances of these taxa occurs at the δ13C excursion coincident with the extinction of 50% of the small benthic foraminiferal taxa. The entire water column was affected by this faunal turnover (surface, intermediate, deep dwellers), but in contrast to benthic foraminifera there was no net loss of habitats since species extinctions of planktic foraminifera were largely replaced by originations.