Grand Canyon carved by flood? Geologist says no

Could the origins of the Grand Canyon lie in an enormous flood? The answer is no, says geologist Bill Dickinson, professor at the University of Arizona in Tucson. Tracing the history of the Grand Canyon is controversial. The deep gorge exposes a billion years of Earth history in its candy-colored cliffs, but geologists can't agree when it formed, or exactly how. A recognized geologist hopes at least to lay to rest one hypothesis: That an ancient lake carved the canyon through a cascading series of waterfalls. A favored concept for two decades, "I don't think it's a valid story, and my main purpose is to dismantle it," the professor says. Read more here. a http://bit.ly/RCfzx3

How do you think the Grand Canyon was formed?