Available evidence suggests that dinosaurs in the San Juan Basin survived the event responsible for the creation of an iridium-enriched zone that has been discovered at or near the Cretaceous/Tertiary boundary at several locations throughout the world. The iridium zone has been found at two separate localities in the Raton Basin coincident with the palynologic Cretaceous/Tertiary boundary. The iridium zone has been searched for in the San Juan Basin at several localities where the palynologic Cretaceous/Tertiary boundary has been bracketed, but it has not been found. It is unlikely that the iridium zone will be found in the San Juan Basin, because stratigraphic studies indicate that the rocks which could have contained the iridium zone were eroded prior to deposition of the Ojo Alamo Sandstone. The significant fact is that dinosaur bone has been found within the Ojo Alamo Sandstone in the San Juan Basin stratigraphically higher than the palynologic Cretaceous/Tertiary boundary; thus, this bone apparently postdates the event that created the iridium zone.