Abstract
Both the Chicxulub and Boltysh impact events are associated with the K-Pg boundary. While Chicxulub is firmly linked to the end-Cretaceous mass extinction, the temporal relationship of the ~24-km-diameter Boltysh impact to these events is uncertain, although it is thought to have occurred 2 to 5 ka before the mass extinction. Here, we conduct the first direct geochronological comparison of Boltysh to the K-Pg boundary. Our 40Ar/39Ar age of 65.39 ± 0.14/0.16 Ma shows that the impact occurred ~0.65 Ma after the mass extinction. At that time, the climate was recovering from the effects of the Chicxulub impact and Deccan trap flood volcanism. This age shows that Boltysh has a close temporal association with the Lower C29n hyperthermal recorded by global sediment archives and in the Boltysh crater lake sediments. The temporal coincidence raises the possibility that even a small impact event could disrupt recovery of the Earth system from catastrophic events.
| Original language | English |
|---|---|
| Article number | eabe6530 |
| Journal | Science Advances |
| Volume | 7 |
| Issue number | 25 |
| DOIs | |
| Publication status | Published - 18 Jun 2021 |
Bibliographical note
AcknowledgmentsWe acknowledge the facilities, and the scientific and technical assistance, of the Imaging Spectroscopy and Analysis Centre, University of Glasgow and the Argon Isotope Facility, SUERC. We further acknowledge R. Grieve and P. Renne for providing samples of Boltysh core B50 and IrZ sanidine, respectively; and A. Ebinghaus for assisting with sampling core 42/11. Funding: Analyses for this work were funded by the National Environment Research Council (IP/1626/0516: Dating of impact crater events associated with the K-Pg boundary). During this work, A.E.P. was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC PGS-D), the University of Glasgow, and Leverhulme Trust Research project grant number RPG-2018-061. M.R.L. was supported by the Science and Technology Facilities Council through grant ST/N000846/1. Author contributions: A.E.P. and D.F.M. designed the study and experiments and collected argon isotope data. A.E.P. and M.R.L. conducted microanalysis. A.E.P., D.F.M., and M.R.L. wrote the manuscript with input from S.P.K. and D.W.J. who supported interpretation of sedimentary sections, assisted with sample selection, and helped to contextualize new age results. Competing interests: The authors declare that they have no competing interests. Data and materials availability: The raw data for this study is included in the Supplementary Materials.