Mystery of the Megaflood Documentary

In the last lab period, the class watched the documentary Mystery of the Megaflood. The documentary discussed 16,000 miles in Washington State referred to as the Scablands. This area contains tall canyons and huge dry waterfalls, as well as potholes that range up to 1,000 ft deep. There are also enormous, random boulders throughout the area. For years geologists were puzzled by the Scablands, and came up with theories that required the Scablands millions of years to form. These theories included gradual erosion by rivers, both fast paced and slow paced, as well as glaciers from the last Ice Age. Both of these theories were disproved, however. J. Harlen Bretz then came up with a theory that went against all other thinking at the time. Bretz decided that the Scablands were actually formed almost overnight by one giant flood. For a river to flood an area this large, the water would have to be 900 ft deep and have a range of 500 cubic miles. The problem that Bretz was havin, besides convincing the rest of the scientific community, was finding a source of water large enough to cause this giant flood. J.T. Pardee claimed to know where the water came from. 250 miles east of the Scablands, in Missoula, Montana, there are the dry remnant of a lake that show flooding heading in the direction of the Scablands. Another geologist, Matthew Rhodes, came up with the theory that the water from this lake pushed itself through cracks in ice and melted through the glacier using friction. Together these theories seem to fit the mysterious formations found in the Scablands, and evidence even suggests more than one 'megaflood' helped with its creation. Further experimentation and studies show this is probably what occured in the Scablands. Personally, I find this discovery fascinating. I think it's amazing that an entire lake was able to flood through a state hundreds of miles away before running off into the Pacific Ocean. This is definitely a place that I would like to stop and visit because it is hard to imagine boulders large enough they were said to have been laid by giants, and potholes a thousand ft deep.