The Niagara falls were formed by a series of geological events following the Wisconsin glaciation, when the glaciers retreated and melt water formed what eventually became the Great Lakes. Water flowing from the Great Lakes gouged out the Niagara Escarpment.
In our previous Spheres of Influence Beauty in Geology section we highlighted both the geology and tourist potential of Lake Erie. As part of the system of Great Lakes, these majestic geologic features are here thanks to the last ice age.
Not to diminish the magnificence of the Great Lakes, however, there is nothing as resplendent as the raw power and beauty of Niagara Falls – and we have the Great Lakes and glaciers themselves to thank for this glorious geologic natural wonder.
Niagara Falls is located on the Niagara River, which essentially acts as a channel in which Lake Erie drains into Lake Ontario.
The falls span the border between Canada (Ontario) and the United States (New York), and encompass three waterfalls: Horseshoe Falls, American Falls and Bridal Veil Falls.
While Niagara Falls aren’t the tallest falls in the world (that title goes to Angel Falls in Venezuela, at 979 meters tall), they are impressive by their width and sheer volume of water. It is reported that more than 168,000 cubic meters (six million cubic feet) of water go over the falls’ crestline every minute during peak time. It also has the highest flow rate of any waterfall in the world – accounting for the pure power one feels when standing at the precipice.
In a brief summary (I encourage readers to delve into the more complex geologic processes involved than I can get into here – I promise it is fascinating), the falls were formed by a series of geological events following the Wisconsin glaciation, when the glaciers retreated and melt water formed what eventually became the Great Lakes. Water flowing from the Great Lakes gouged out the Niagara Escarpment.
The sedimentary strata of Niagara Falls region include limestone, shale marine and sandstone that were deposited during the Silurian period 430-390 million years ago. The rapids fall over a harder (more erosion resistant) limestone and dolomite from the Lockport Formation (Middle Silurian). The softer underlying strata consist primarily of marine shale of the Rochester Formation (Lower Silurian). This shale was easily eroded, undercutting the Lockport, and eventually carving out the falls we see today.
For more information click on any of the links provided below.
Catch up on our Great Lakes series with our last issue:
Beauty in Geology: Lake Erie
For more information about the geology of Niagara Falls:
Origins of Niagara
Niagara Falls Info
Niagara Falls Geology: Facts and Figures
Graphic Representation of Niagara Escarpment