LATE NEOGENE CHRONOLOGY - NEW PERSPECTIVES IN HIGH-RESOLUTION STRATIGRAPHY

We present an integrated geochronology for late Neogene time (Pliocene , Pleistocene, and Holocene Epochs) based on an analysis of data from stable isotopes, magnetostratigraphy, radiochronology, and calcareous plankton biostratigraphy. Discrepancies between recently formulated as tronomical chronologies and magneto-chronologies for the past 6 m.y. h ave been resolved on the basis of new, high-precision Ar/Ar ages in th e younger part of this interval, the so-called Brunhes, Matuyama. and Gauss Epochs (= Chrons C1n-C2An; 0-3.58 Ma), and revised analysis of s ea floor anomalies in the Pacific Ocean in the older part, the so-call ed Gilbert Epoch (= Chron C2Ar-C3r; 3.58-5.89 Ma). The magneto- and as trochronologies are now concordant back to the Chron C3r/C3 An boundar y at 5.89 Ma. The Neogene (Miocene, Pliocene, Pleistocene, and Holocen e) and Paleogene are treated here as period/system subdivisions of the Cenozoic Era/Erathem, replacements for the antiquated terms Tertiary and Qua ternary, The boundary between the Miocene and Pliocene Series (Messinian/Zanclean Stages), whose global stratotype section and point (GSSP) is currently proposed to be in Sicily, is located within the r eversed interval just below the Thvera (C3n.4n) Magnetic Polarity Subc hronozone with an estimated age of 5.32 Ma. The Pliocene/Pleistocene b oundary, whose GSSP is located at Vrica (Calabria, Italy), is located near the top of the Olduvai (C2n) Magnetic Polarity Sub-chronozone wit h an estimated age of 1.81 Ma. The 13 calcareous nannoplankton and 48 planktonic foraminiferal datum events for the Pliocene, and 12 calcare ous nannoplankton and 10 planktonic foraminiferal datum events for the Pleistocene, are calibrated to the newly revised late Neogene astrono mical/geomagnetic polarity time scale.