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.

全球白垩纪白垩纪（K-Pg）灭绝的特征是铱的浓度升高，这是由于六千六百万年前的超高速撞击事件所致。在这里，我们报告了来自四个独立实验室的新数据，这些数据揭示了由IODP-ICDP Expedition 364回收的钻芯中Chicxulub冲击结构的峰-环序列内的铱正异常。 -撞击火山口峰环的沉积物，恰好位于最下层的达尼中层石灰石下方。撞击事件发生后的数十年至数十年间，Chicxulub撞击盆地的这一部分返回到能量相对较低的沉积环境，以前所未有的细节记录了随后的几千年中生命的恢复。