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Title: Globally distributed iridium layer preserved within the Chicxulub impact structure
The Cretaceous-Paleogene (K-Pg) mass extinction is marked globally by elevated concentrations of iridium, emplaced by a hypervelocity impact event 66 million years ago. Here, we report new data from four independent laboratories that reveal a positive iridium anomaly within the peak-ring sequence of the Chicxulub impact structure, in drill core recovered by IODP-ICDP Expedition 364. The highest concentration of ultrafine meteoritic matter occurs in the post-impact sediments that cover the crater peak ring, just below the lowermost Danian pelagic limestone. Within years to decades after the impact event, this part of the Chicxulub impact basin returned to a relatively low-energy depositional environment, recording in unprecedented detail the recovery of life during the succeeding millennia. The iridium layer provides a key temporal horizon precisely linking Chicxulub to K-Pg boundary sections worldwide.  more » « less
Award ID(s):
1737155 1737087 1737199
NSF-PAR ID:
10244218
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; « less
Date Published:
Journal Name:
Science Advances
Volume:
7
Issue:
9
ISSN:
2375-2548
Page Range / eLocation ID:
eabe3647
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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