Plio-Pleistocene planktonic foraminifera biostratigraphy and biochronology

Planktonic foraminifera have one of the most complete fossil records, and thanks to their overwhelming abundance in the oceans, they provide great means for dating and correlation of marine sediments. Effective use of planktonic foraminifera requires a good knowledge of species biostratigraphic ranges with reliable age calibrations for their evolution and extinction. The current biochronology combines data from a small number of localities and in many cases relies on age-calibrations from a single site. Studies from multiple sites and various regions are required to test reliability of these calibrations and to replace them with new regional ages if necessary. The deep-sea drill cores recovered during recent International Ocean Discovery Program (IODP) expeditions to the Indo-Pacific (Exp. 363) and South Atlantic (Exp. 390/393), contain abundant and well-preserved assemblages of planktonic foraminifera. Reliable magneto-stratigraphic age control throughout Plio-Pleistocene sedimentary sequences, provides great opportunity to re-address and re-calibrate many of the bioevents. Our initial study of the sampled material led to description of a new species of fossil planktonic foraminifera and allowed the identification of a number of bioevents with timing contrasting from published ages. Results of ongoing research will provide new high-resolution data, improving global biostratigraphy and biochronology of Plio-Pleistocene planktonic foraminifera.