EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Astronomical calibration of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain

Mingsong Li1,2, Timothy Bralower2, Lee Kump2, Jean Self-Trail3, James Zachos4, William Rush4,5,6, and Marci Robinson3
Mingsong Li et al.
  • 1School of Earth and Space Sciences, Peking University, Beijing 100871, China (
  • 2Department of Geosciences, Pennsylvania State University, University Park, PA 16802, USA
  • 3Florence Bascom Geoscience Center, U.S. Geological Survey, Reston, VA 20192, USA
  • 4Department of Earth and Planetary Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, USA
  • 5Department of Earth and Planetary Sciences, Yale University, New Haven, CT 06511, USA
  • 6Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, CO 80309, USA

The chronology of the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma) remains disputed, hampering complete understanding of the possible trigger mechanisms of this event. Here we present an astrochronology for the PETM carbon isotope excursion from Howards Tract, Maryland a paleoshelf environment, on the mid-Atlantic Coastal Plain. Statistical evaluation of variations in calcium content and magnetic susceptibility indicates astronomical forcing was involved and the PETM onset lasted about 6 kyr. The astrochronology and Earth system modeling suggest that the PETM onset occurred at an extreme in precession during a maximum in eccentricity, thus favoring high temperatures, indicating that astronomical forcing could have played a role in triggering the event. Ca content data on the paleo-shelf, along with other marine records, support the notion that a carbonate saturation overshoot followed global ocean acidification during the PETM.

How to cite: Li, M., Bralower, T., Kump, L., Self-Trail, J., Zachos, J., Rush, W., and Robinson, M.: Astronomical calibration of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-3800,, 2023.