AFTERMATH: Atmospheric Fallout of Chicxulub impact dust and the global Terrestrial Ecosystem Response: MApping The earliest History of the Paleogene (FWOTM1273)

Sixty-six million years ago, the Chicxulub asteroid impact triggered one of Earth’s most extreme biodiversity crises. The global dispersal of impact-generated fine dust created a prolonged impact winter, plunging Earth into darkness, halting photosynthesis, and causing a rapid mass extinction of 75% of life, including the non-avian dinosaurs. This project, AFTERMATH, aims to unravel the short-term ecosystem responses on land to the Chicxulub impact dust plume. Early findings indicate a two-year shutdown of photosynthesis after impact, but the extent and duration of biosphere responses across the globe remain unknown. Therefore, well-preserved, organic-rich sediments at terrestrial Cretaceous-Paleogene boundary sites in New Zealand, North America, and South America are sampled at a millimeter resolution. By applying innovative inorganic and organic geochemical, sedimentological, and palynological analyses alongside cutting-edge paleoclimate modeling, AFTERMATH reconstructs in high detail the timing and geographic variability of land plant extinction and recovery. This work will provide new insights into life’s resilience, offering critical lessons for the modern-day biodiversity and climate crises. From the settling of dust and rise of pioneering ferns to the re-emergence of lush forests, this project captures the rebirth of life after disaster—shedding a new light on how our planet responds in the aftermath of catastrophe.

Keywords:Cretaceous-Paleogene boundary, Impact dust plume, Terrestrial ecosystem dynamics

Disciplines:Sedimentology, Geochemistry not elsewhere classified, Stratigraphy, Palaeontology, Extraterrestrial geology