An extraterrestrial impact in the early Danian: a secondary K/T boundary event?

High-resolution lithostratigraphic and foraminiferal studies of a section s panning the Cretaceous/Tertiary (K/T) boundary at Poty, Pernambuco, in nort h-eastern Brazil, indicate a possible extraterrestrial bolide impact in the earliest Danian, approximately at the boundary between the P alpha and Pla foraminiferal zones (approximate to 100,000-200,000 years after the K/T tr ansition), in southern Atlantic low-latitude regions. Tsunami deposits have been related to the Chicxulub impact structure in Mexico and dating of a s imilar deposit at Poty suggests a slightly later event here. Hypothetically , the presence of Danian fauna in older sediments could have been caused by multiple re-working events of unconsolidated Chicxulub distal impact eject a or bioturbation. However, identical microfossil distributions occur in ot her sampled sections, thereby excluding that possibility. It is possible th at there were multiple cometary impacts during a few hundred thousand years around the WT transition.