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Title: Solar System chaos and the Paleocene–Eocene boundary age constrained by geology and astronomy
Astronomical calculations reveal the Solar System’s dynamical evolution, including its chaoticity, and represent the backbone of cyclostratigraphy and astrochronology. An absolute, fully calibrated astronomical time scale has hitherto been hampered beyond ~50 million years before the present (Ma) because orbital calculations disagree before that age. Here, we present geologic data and a new astronomical solution (ZB18a) showing exceptional agreement from ~58 to 53 Ma. We provide a new absolute astrochronology up to 58 Ma and a new Paleocene–Eocene boundary age (56.01 ± 0.05 Ma). We show that the Paleocene–Eocene Thermal Maximum (PETM) onset occurred near a 405-thousand-year (kyr) eccentricity maximum, suggesting an orbital trigger. We also provide an independent PETM duration (170 ± 30 kyr) from onset to recovery inflection. Our astronomical solution requires a chaotic resonance transition at ~50 Ma in the Solar System’s fundamental frequencies.  more » « less
Award ID(s):
1658023
PAR ID:
10133086
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Science
Volume:
365
Issue:
6456
ISSN:
0036-8075
Page Range / eLocation ID:
926 to 929
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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