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Early Pliocene (Zanclean) stratigraphic framework for PRISM5/PlioMIP3 time slices

September 15, 2023

Global reconstructions of Pliocene climate provide important insights into how the climate system operates under elevated temperatures and atmospheric CO2 levels. These reconstructions have been used extensively in paleoclimate modeling experiments for comparison to simulated conditions, and as boundary conditions.Most previous work focused on the Late Pliocene interval known as the mid Piacenzian Warm Period (mPWP), the interval originally identified by the U.S. Geological Survey Pliocene Research, Interpretation and Synoptic Mapping Project (PRISM) as the PRISM interval or Mid Pliocene Warm Period. The term Mid Pliocene Warm Period is a misnomer due to changes to the geological time scale, and its use should be discontinued. The Pliocene Model Intercomparison Project (PlioMIP), now in its third phase, is expanding to include a focus on the Early Pliocene (Zanclean). PlioMIP3 experiments will allow comparison of environmental and climatic conditions before and after closure of the Central American Seaway (CAS). PlioMIP3 used the annual insolation pattern at the top of the atmosphere to determine time slices in the Zanclean that have orbital configurations that are most similar to modern. Two have been selected by PlioMIP and adopted by PRISM for inclusion in future studies: PRISM5.1 (4.474 Ma) and PRISM5.2 (4.870 Ma). Here we establish the stratigraphic framework for these Early Pliocene time slices and furnish information to help locate these intervals in proxy records of paleoenvironmental data using oxygen isotope stratigraphy, paleomagnetic stratigraphy, biostratigraphy, and biochronology (calibrated planktic foraminifer and calcareous nannofossil events).

Publication Year 2023
Title Early Pliocene (Zanclean) stratigraphic framework for PRISM5/PlioMIP3 time slices
DOI 10.29041/strat.20.3.02
Authors Harry J. Dowsett, Marci M. Robinson, Kevin M. Foley, Steve Hunter, Aisling M Dolan, Julia C. Tindall
Publication Type Article
Publication Subtype Journal Article
Series Title Stratigraphy
Index ID 70248678
Record Source USGS Publications Warehouse
USGS Organization Florence Bascom Geoscience Center