TY - JOUR
T1 - The first day of the Cenozoic
AU - Gulick, Sean P.S.
AU - Bralower, Timothy J.
AU - Ormö, Jens
AU - Hall, Brendon
AU - Grice, Kliti
AU - Schaefer, Bettina
AU - Lyons, Shelby
AU - Freeman, Katherine H.
AU - Morgan, Joanna V.
AU - Artemieva, Natalia
AU - Kaskes, Pim
AU - De Graaff, Sietze J.
AU - Whalen, Michael T.
AU - Collins, Gareth S.
AU - Tikoo, Sonia M.
AU - Verhagen, Christina
AU - Christeson, Gail L.
AU - Claeys, Philippe
AU - Coolen, Marco J.L.
AU - Goderis, Steven
AU - Goto, Kazuhisa
AU - Grieve, Richard A.F.
AU - McCall, Naoma
AU - Osinski, Gordon R.
AU - Rae, Auriol S.P.
AU - Riller, Ulrich
AU - Smit, Jan
AU - Vajda, Vivi
AU - Wittmann, Axel
N1 - Funding Information:
ACKNOWLEDGMENTS. We thank the captain and crew, drilling team, and technical staff who participated in shipboard and/or shore-based operations. We thank the editor and 2 anonymous reviewers. W. Zylberman and J. Gattacceca are thanked for assistance with paleomagnetic measurements. Data and samples can be requested from IODP. The European Consortium for Ocean Research Drilling (ECORD) implemented Expedition 364 with funding from the IODP and the ICDP. US participants were supported by the US Science Support Program and National Science Foundation Grants OCE 1737351, OCE 1736826, OCE 1737087, OCE 1737037, OCE 1736951, and OCE 1737199. J.O. was partially supported by Grants ESP2015-65712-C5-1-R and ESP2017-87676-C5-1-R from the Spanish Ministry of Economy and Competitiveness and Fondo Europeo de Desarrollo Regional. B.S. thanks Curtin University for an Australian Postgraduate Award. J.V.M. was funded by Natural Environment Research Council Grant NE/P005217/1. K. Grice thanks Australia Research Council for Grant DP180100982 and Australia New Zealand IODP Consortium for funding. The Vrije Universiteit Brussel group is supported by Research Foundation Flanders (FWO) and BELSPO; P.K. is an FWO PhD fellow. This is University of Texas Institute for Geophysics Contribution 3634.
Funding Information:
The European Consortium for Ocean Research Drilling (ECORD) implemented Expedition 364 with funding from the IODP and the ICDP. US participants were supported by the US Science Support Program and National Science Foundation Grants OCE 1737351, OCE 1736826, OCE 1737087, OCE 1737037, OCE 1736951, and OCE 1737199. J.O. was partially supported by Grants ESP2015-65712- C5-1-R and ESP2017-87676-C5-1-R from the Spanish Ministry of Economy and Competitiveness and Fondo Europeo de Desarrollo Regional. B.S. thanks Curtin University for an Australian Postgraduate Award. J.V.M. was funded by Natural Environment Research Council Grant NE/P005217/1. K. Grice thanks Australia Research Council for Grant DP180100982 and Australia New Zealand IODP Consortium for funding. The Vrije Universiteit Brussel group is supported by Research Foundation Flanders (FWO) and BELSPO; P.K. is an FWO PhD fellow. This is University of Texas Institute for Geophysics Contribution 3634
Publisher Copyright:
© 2019 National Academy of Sciences. All rights reserved.
PY - 2019/9/24
Y1 - 2019/9/24
N2 - Highly expanded Cretaceous-Paleogene (K-Pg) boundary section from the Chicxulub peak ring, recovered by International Ocean Discovery Program (IODP)-International Continental Scientific Drilling Program (ICDP) Expedition 364, provides an unprecedented window into the immediate aftermath of the impact. Site M0077 includes ∼130 m of impact melt rock and suevite deposited the first day of the Cenozoic covered by <1 m of micrite-rich carbonate deposited over subsequent weeks to years. We present an interpreted series of events based on analyses of these drill cores. Within minutes of the impact, centrally uplifted basement rock collapsed outward to forma peak ring capped in melt rock. Within tens of minutes, the peak ring was covered in ∼40 m of brecciated impact melt rock and coarsegrained suevite, including clasts possibly generated by melt-water interactions during ocean resurge. Within an hour, resurge crested the peak ring, depositing a 10-m-thick layer of suevite with increased particle roundness and sorting.Within hours, the full resurge deposit formed through settling and seiches, resulting in an 80-m-thick fining-upward, sorted suevite in the flooded crater. Within a day, the reflected rim-wave tsunami reached the crater, depositing a cross-bedded sand-to-fine gravel layer enriched in polycyclic aromatic hydrocarbons overlain by charcoal fragments. Generation of a deep crater open to the ocean allowed rapid flooding and sediment accumulation rates among the highest known in the geologic record. The high-resolution section provides insight into the impact environmental effects, including charcoal as evidence for impactinduced wildfires and a paucity of sulfur-rich evaporites from the target supporting rapid global cooling and darkness as extinction mechanisms.
AB - Highly expanded Cretaceous-Paleogene (K-Pg) boundary section from the Chicxulub peak ring, recovered by International Ocean Discovery Program (IODP)-International Continental Scientific Drilling Program (ICDP) Expedition 364, provides an unprecedented window into the immediate aftermath of the impact. Site M0077 includes ∼130 m of impact melt rock and suevite deposited the first day of the Cenozoic covered by <1 m of micrite-rich carbonate deposited over subsequent weeks to years. We present an interpreted series of events based on analyses of these drill cores. Within minutes of the impact, centrally uplifted basement rock collapsed outward to forma peak ring capped in melt rock. Within tens of minutes, the peak ring was covered in ∼40 m of brecciated impact melt rock and coarsegrained suevite, including clasts possibly generated by melt-water interactions during ocean resurge. Within an hour, resurge crested the peak ring, depositing a 10-m-thick layer of suevite with increased particle roundness and sorting.Within hours, the full resurge deposit formed through settling and seiches, resulting in an 80-m-thick fining-upward, sorted suevite in the flooded crater. Within a day, the reflected rim-wave tsunami reached the crater, depositing a cross-bedded sand-to-fine gravel layer enriched in polycyclic aromatic hydrocarbons overlain by charcoal fragments. Generation of a deep crater open to the ocean allowed rapid flooding and sediment accumulation rates among the highest known in the geologic record. The high-resolution section provides insight into the impact environmental effects, including charcoal as evidence for impactinduced wildfires and a paucity of sulfur-rich evaporites from the target supporting rapid global cooling and darkness as extinction mechanisms.
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U2 - 10.1073/pnas.1909479116
DO - 10.1073/pnas.1909479116
M3 - Article
C2 - 31501350
AN - SCOPUS:85072638126
SN - 0027-8424
VL - 116
SP - 19342
EP - 19351
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 39
ER -