The famous Floridian, Nik Wallenda, has walked across Niagara Falls and the Grand Canyon. Both are magnificent gorges cut by rivers that presented the aerialist with geographic challenges worthy of his skills.
But what were the similarities and differences between the two landmarks?
Having sailed for years, I appreciate fluctuating temperatures and local offshore winds, but coping with a drop below me of hundreds of feet is another matter.
Niagra Falls and the Grand Canyon: Origins of the Gorges
Niagara Falls and the Grand Canyon were both cut through sedimentary rock deposited by water. In the case of Niagara Falls, the Niagara River, as far back as the glacial period, became the main outlet for the upper lakes and eroded back the Niagara Escarpment as it flowed over it from west to east.
Science estimates that Niagara Falls has eroded the gorge back 11.4 kilometers (7.1 miles) during the last 12,300 years.
The Niagara Escarpment, however, formed long before the glaciations, dating back over 415 million years to the time of the great inland seas; even before the dinosaurs. Sediments were laid down, layer by layer in a basin formation. Then, through differential erosion, the softer layers were worn down leaving the hard dolomite of the escarpment as a ridge.
Like the deposits that formed the Niagara Escarpment, many of the sediments in the lower levels of the Grand Canyon were deposited in inland seas above a vulcanic base. Later, uplift raised the sediments to form the Colorado Plateau. The uplift steepened the gradient of the Colorado River, increasing the rate of water flow and the speed of erosion.