Astrochronology of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain

Mingsong Li; Timothy J. Bralower; Lee R. Kump; Jean Self-Trail; James C. Zachos; William D. Rush; Marci M. Robinson

doi:10.1038/s41467-022-33390-x

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Astrochronology of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain

Mingsong Li·Timothy J. Bralower·Lee R. Kump·Jean Self-Trail·James C. Zachos·William D. Rush·Marci M. Robinson

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Abstract

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.

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Nature Communications Article

Source-reported bounding extent: 36.54494944148322° to 40.463666324587685° latitude; -78.01391601562499° to -73.970947265625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Mingsong Li, Timothy J. Bralower, Lee R. Kump, Jean Self-Trail, James C. Zachos, William D. Rush, Marci M. Robinson. 2022-09-24. Astrochronology of the Paleocene-Eocene Thermal Maximum on the Atlantic Coastal Plain. https://doi.org/10.1038/s41467-022-33390-x

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