Type in "Comet Yucatan tsunami" into Google and you get lots of links.
As an example, evidence in Arkansas of giant bolders being transported by tsunami from the Yucatan blast site 400 miles away.
http://www.science-frontiers.com/sf121/sf121p10.htm
For you eggheads, here is a wonderfully complicated study on the effects of a comet hitting the earth . . . . but check out the tsunami section where the prediction of "several mile high waves that could travel several hundred miles inland. . . . . " Still, there are some doubters as the author notes.
http://personals.galaxyinternet.net/tunga/TA.pdf
Cowperson