As it stands today, The American Falls has an erosion rate of about 3 to 4 inches per year. The biggest factor for the American Falls is the fact that it has cracks at the Crestline in the top cap rock layer. Underneath is another softer shale layer. The action of lifting water coming through these cracks causes them to become larger and along with the freezing and thawing each year, the rock structure continues to weaken until that part finally cracks and falls off. It is not strong enough to cause major erosion of the rocks at the bottom of the falls. The Niagara River is about 58 kilometres (36 mi.) in length and is the natural outlet from Lake Erie to Lake Ontario, wow that is super big. And the elevation between the two lakes is about 99 metres which is 326 ft. Niagara Falls itself has eroded 11.4 kilometers (which is 7.1 miles) during the last 12,300 years.
In order to log a find on this cache you will have to email me the answers to these questions.
1. Why do you think the flow at Niagara Falls is not strong enough to cause major erosion to the rocks at the bottom of the fall?
2. Give a hypothesis about what the American Falls will eventually look like? (how the structure will change with the erosion)
3. Before you read about this what would you think was the erosion rate per year in inches, once you have read this and researched a bit, now knowing what you know, what do you think the erosion rate per year is.
4. This question is for fun but is recommended for a full geoscience lesson, what is the total area drained by the Niagara River in square kilometers or miles.
5. (Optional) Take a picture of yourself with the American Erosion behind you and post it in your log.
To email me the answers you have to click on my username above on the cache page, just in case you didnt know.
Hope you enjoy!