| A, B: Clasts from the basal conglomerate of the event deposit contain Chicxulub impact spherules. C, D: spherules in mudstone clasts. E, F: spherules within cracks of mudstone clasts. E: cracks rimmed by sparry calcite. Insert shows morphology of crack and total length of ~2 cm. F: clast with cracks infilled with spherules and sparry calcite, then truncated by erosion and followed by normal sedimentation. These clasts reveal a history of Chicxulub ejecta fallout and lithification well prior to exposure to erosion, transport and redeposition at the base of the event deposit. Credit: GSA |