Planktonic foraminiferal biostratigraphy in the Equatorial Pacific

Planktonic foraminiferal datums for the Pleistocene of the Equatorial Pacific have frequently been shifted vertically by dissolution and bioturbation. Evolutionary initial appearances and final extinctions are altered to first and last lithostratigraphic occurrences, respectively. Shallow cores with high sedimentation rates are least affected by these processes and provide the most reliable chronostratigraphic resolution. Ten datum levels are proposed for the Quaternary and five for the latest Pliocene, all of which have been dated by palaeomagnetic stratigraphy.