2006-10-15 06:22:53 · 6 answers · asked by steve h 1 in Education & Reference ➔ Homework Help
The force of the water going over the falls, and the material that the river carries cut back the edge of the falls and the softer rocks underneath the edge of the falls so that position of the Falls erodes back up stream.
"The famous American Niagara Falls used to cut back at a rate of 1 m (3 feet) per year until half of its supply of 5,700 cubic m/sec (90 million gpm) was diverted for hydroelectric power generation."-USGS site
According to the iaw.com site, the Falls have eroded "11.4 kilometers (7.1 miles) during the last 12,300 years"
Go to the iaw.com site (see below) for a lot of information about the Falls, erosion rates, history and so forth.
2006-10-15 06:42:11 · answer #1 · answered by luka d 5 · 1⤊ 0⤋
Nature changes daily. Nothing looks the way it did centuries ago.
2006-10-15 13:24:57 · answer #2 · answered by sesamenc 4 · 0⤊ 0⤋
Erosion is the displacement of solids (soil, mud, rock and other particles) by the agents of wind, water or ice, by downward or down-slope movement in response to gravity or by living organisms (in the case of bioerosion).
2006-10-15 13:31:49 · answer #3 · answered by cather2000 2 · 1⤊ 0⤋
It's called erosion.
2006-10-15 13:24:45 · answer #4 · answered by Anonymous · 0⤊ 0⤋
because we are using the water to generate power.
Why am I doing your homework for you?
2006-10-15 13:25:01 · answer #5 · answered by draftboyg 4 · 1⤊ 0⤋
erosion.
2006-10-15 13:25:15 · answer #6 · answered by cooltoque 4 · 0⤊ 1⤋