There is some outstanding examples of natural history, concerning the end of the last ice age 12,000 years ago, elsewhere in Niagara County, NY. All of the features described here are on main roads. Here is a map link http://www.maps.google.com/ .
THE LOCKPORT GLACIAL IMPACT CRATER
Lockport, NY is the city at the approximate geographical center of Niagara County. If we drive northward on Transit Road, one of the main roads of Niagara County, when we are just south of Lockport, there will be a small hill between Dorchester Road and Lincolnshire Drive. Following that hill, we go into a drop with the bottom at Gaffney Road.
This is yet another glacial impact crater, similar to those in Niagara Falls. If we continue northward, the ground gets higher north of Gaffney Road but then we come to a steep drop beginning at High Street. This drop was formed by a vast mass of ice sliding southward across the general slope of the underlying rock strata as the glacier began to melt and break apart at the end of the last ice age.
This ice plowed and compressed the ground here and then, for about 8,000 years, this was part of the southern shore of the former Lake Tonawanda. The deepest point of the lake in the area can be seen to be where Transit Road crosses West Main Street in Lockport. Going north from there the ground gets higher, but more gradually.
This was once the northern extent of Lake Tonawanda in the area. But at the end of the ice age, the ice that formed this slope fractured laterally after pressing up against the slope. A vast slab of ice slid off the top and struck the ground south of where the ice was pressed against this slope. This created the crater with it's low point at the intersection of Transit Road and Gaffney Road.
THE GLACIAL RIDGES OF NIAGARA COUNTY
Although it is often not very noticable, there is a southward slope to the land above the escarpment in Niagara County. From Upper Mountain Road, it is easy to see that the ground gets lower going southward from the escarpment. From Mapleton Road, the southward drop is easily visible looking down Main Road. The canal acts as a builder's level in that it makes it easy to see how the ground is sloped downward to the south. The further north we go along the canal, the further is the drop down to the water level.
At the end of the last ice age great bergs of ice broke loose from the melting glacier, which might have been a kilometer or two thick, and slid across this slope. These bergs plowed up a vast amount of soil and debris and when they had melted enough so as to be unable to push the debris any further, it remained as a glacial ridge.
The area of Niagara County between the cities of Lockport and North Tonawanda holds two parallel glacial ridges. While such glacial ridges will probably exist anywhere that there were glaciers and a large-scale slope to the land, it may be that two such parallel ridges may not exist anywhere else. The two ridges are roughly equal in length and about two km apart. They are easy to find on a map and to see while driving because they both host main roads along their crests.
The furthest south, and which must have formed first, has Bear Ridge Road along it's crest. This magnificent glacial ridge runs along the road between Killian Road and Campbell Boulevard. There are two more short sections of the ridge if we continue northeastward past Campbell Boulevard.
If we take Campbell Boulevard northward and turn west on Beach Ridge Road, we can see the younger of the two ridges. This ridge is further north than the other because it formed later when the climate had grown somewhat warmer and the sliding bergs of ice that formed this ridge melted before they could push the soil and debris that formed the ridge any further.
To get an idea of how these ridges formed, we need only look at the vast dips that have been carved out of the land over which roads now pass. On Mapleton Road, on opposite sides of the Starpoint School Complex, we can see a hill where Aiken and Mapleton Roads intersect and another such hill on Mapleton Road just east of Townline Road. To the north on Lockport Road, it is easy to see several such wide dips if we move eastward. This is where vast sections of earth were plowed up by the glacier and ended up in the two ridges.
Glaciers, by the way, are good for farming because in plowing up the soil to considerable depths, they recycle nutrients that would otherwise remain far under the ground. In areas that glaciers did not reach during the ice ages, the soil will get depleted more quickly.
Much of Chestnut Ridge Road between Gasport and Lockport is yet another stretch of glacial ridge. This one is much closer to the escarpment. The hilly southeastern portion of the county is filled with smaller glacial ridges. South of Lockport along Rapids Road, there is a glacial ridge between Old Beattie and Raymond Roads. Not far away Crosby Road, east of Raymond Road, is possibly a continuation of the one just to the north. If we go east on Bunker Hill Road and continue north on Royalton Center Road, there are such glacial ridges all around.
The reason that glacial ridges do not exist to this extent in the western parts of the county, around Niagara Falls, is that the sliding bergs of ice from the melting glacier pushed all the way south to Tonawanda or west to the Canadian side of Niagara Falls. This was because the slope of the ground was somewhat steeper than in the western half of the county. You will notice on a map that the Erie Canal which cuts across the county does not cross it's hilly eastern portion south of the escarpment but goes around it.
Notice that the glacial ridges in this area tend to be aligned from southwest to northeast. The reason for this is simple. I have already described how the underlying rock strata in the county above the escarpment is tilted downward as we go south. But there is also a less-obvious downward tilt going east that I cannot see is even perceptible to the human eye.
If we look at how high the escarpment is at Lewiston, at the western end of Niagara County, in comparison with it's height at Middleport, at the eastern end, it is clear that there is also a downward slope as we go eastward. This caused the broken fragments of glacier at the end of the last ice age to slide to the southeast, hence the directional alignment of the ridges. The exception is Chestnut Ridge, because it is close to the edge of the escarpment.
Our final glacial ridge in Niagara County is located below the escarpment. The section of North Ridge Road from Ridge Road to Cambria-Wilson Road is yet another fine example of a glacial ridge. We can see that glacial ridges below the escarpment are less extensive then those above it. This is simply because the slope to the ground is greater above the escarpment and so it provided the sliding ice with more momentum.
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