At the Chicxulub site glassy material suddenly appears in the limestone at a certain depth along with shattered rock. They have been found in the vicinity of many impact craters. There are a variety of such minerals, known as impactites, which are associated with ancient craters. In a few cases meteorite fragments are found associated with the crater. These and other clues, often found together, have ruled out the usual geologic alternatives such as old volcanic craters, natural basins, etc.
Traditional geology stands vindicated.
Obviously, the major strata of the geologic column have been laid down over the ages. Those ages have seen the impact of many large asteroids, each in itself a rare event. Major impacts are obviously rare, being that none have occurred during recorded history. Therefore, creationists must conjure up a miraculous swarm of asteroids which decide to drop in on Earth throughout the year of Noah's flood. They fall here and there without destroying the ark with milehigh waves or blast effects far exceeding that of any atomic bomb.