^1,2Birger Schmitz,³Yue Cai,^2.4Shiyong Liao,⁵Victoriano Pujalte,³Ting Ruan,⁶Robert P. Speijer,^7,8Ellen Thomas
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.70082]
¹Astrogeobiology Laboratory, Department of Physics, Lund University, Lund, Sweden
²Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing, China
³State Key Laboratory of Paleobiology and Stratigraphy, Nanjing Institute of Geology and Paleontology, Chinese Academy ofSciences, Nanjing, China
⁴Chinese Academy of Sciences, Center for Excellence in Comparative Planetology, Hefei, China
⁵Department of Geology, Faculty of Science and Technology, University of the Basque Country, Bilbao, Spain
⁶Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
⁷Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
⁸Department of Earth and Environmental Sciences, Wesleyan University, Middletown, CT, USA
Published by arrangement with John Wiley & Sons

Almost 10 years have passed since microtektites and microkrystites were reportedfor the Paleocene–Eocene (P–E) boundary in drill cores and outcrop in New Jersey and inODP Hole 1051B in the western North Atlantic. The glassy spherules were interpreted toreflect an impact trigger for the Paleocene–Eocene Thermal Maximum (PETM). Since then,many detailed studies of sediment strata across the P–E boundary worldwide have beenperformed, but so far, no additional reports of impact spherules have been published.Negative results usually are not published, but here we report a lack of success in finding suchspherules at the P–E boundary in ODP Hole 1051B. We searched 90 g of sediment from thesame interval in the same core from which 56 impact spherules >63 lm were previouslyreported from 35 g of sediment, but did not find microtektites or microkrystites. We also didnot find impact spherules in a detailed search of 2.3 kg of sediment from the P–E boundary inthe Zumaia section (Spain), where the boundary is marked by a minor iridium anomaly. Inaddition, we did not find such spherules in P–E boundary sediment from sections in Europeand the Middle East nor in drill cores from the southern Atlantic. We urge the researchcommunity to report further both negative and positive results on this issue in order toelucidate the envisioned P–E boundary impact event.