THE MYSTERY OF THE NORTHEASTERN UNITED STATES AND EASTERN CANADA
The physical geography of the New England and eastern Canada region is more puzzling and challenging to figure out than any crossword or Sudoku puzzle that I have ever seen. Today, I would like to have a try at explaining it.
This difficult-to-explain geography is the result of the long-ago tectonic collision which formed the system of ridges and mountains, known as the Appalachians. The collision took place between what is now North America and what is now Africa.
Most of Africa was cut away by the line of volcanic activity along the Mid-Atlantic Ridge, which runs along the floor of the Atlantic Ocean from north to south. On a map showing ocean depths, you can see how both the curve of the west coast of north Africa and the curve of the North American Continental Shelf match the curve of the Mid-Atlantic Ridge in between the two.
The two hemispheres have been moving apart ever since due to spreading of the seafloor along the line of the ridge. The front of the sliding collision between the two great land masses remains in North America as the Appalachians.
The front of the collision shifted from a southwest to northeast line to a more east-west line. This formed a curve in the mountains and ridges of the Appalachians, with the focal point of the curve at Harrisburg in Pennsylvania. The reason for this shift is that the front of the collision approached the hard rock of the Canadian Shield, the layer of dense rock underlying the eastern half of Canada.
The "focal point" of the curve in the Appalachian system of ridges and mountains is around Harrisburg, Pennsylvania.
On the outside of the curve in the collision front the land was forced upward, resulting in the Allegheny Plateau. Further east along the line of the collision, the Catskill Mountains are also the remains of an old plateau that has been unevenly eroded to form the low mountains of today.
The Adirondack Mountains are sometimes classified with the Appalachians, due to their location. But the Adirondacks are technically a southward extension of the Canadian Shield, that has been forced upward into a broad dome. I see this as being the result of pressure due to the collision which formed the Appalachians.
Now, here is the mystery. Long Island, in New York State just east of New York City, is formed as a continuation of the ridges of the Appalachians. On a physical geography map, it is easy to see that the two parallel "spines" of Long Island continue in a straight line from the ridges running east-west across Pennsylvania.
But yet the ridges in Pennsylvania also shift to a north-south line across northern New Jersey. So, we can see that the ridges of the Appalachians across Pennsylvania split into two nearly perpendicular lines of which the east-west line is visible on the map as Long Island. The other, nearly north-south, line extends around the southeast corner of the Catskills and proceeds toward the southern extent of the Green Mountains of Vermont.
Here is my theory of how this came to be. The momentum and the sharp turn at the southeast corner of the Catskills and Adirondacks caused part of what is now Africa to break away from the rest, and the remainder to continue the parallel sliding tectonic collision with the part that broke away. I find that this explains perfectly the landscape configuration that we see today.
Notice how the front of collision formed mountains just east of the Adirondacks along a line from the Green Mountains of Vermont, extending north and east to form the Gaspe Peninsula of Quebec. But also notice that this lengthy stretch of mountains is not as ridge-like as the rest of the Appalachians. This is because it was more of a direct collision with the section of what is now Africa that broke away that raised this line of mountains.
The scenario here also explains why the Green Mountains fade out from Vermont southward into Connecticut. The impact of the collision with the part of what is now Africa that broke away was much less here just as, if we stand a board straight up while resting on the ground and then let it fall, the impact with the ground will be much greater at what was the top end of the board than at the bottom.
The Green Mountains-Gaspe Peninsula represents what we could the Inner Line of the tectonic collision, where the part of what is now Africa that broke away from the rest collided with the mainland of North America. The rest of what is now Africa continued westward with the collision, sliding against the part of what is now Africa that had broken away, and formed what we will call the Outer Line.
Long Island, Nova Scotia and, the north-south section of Newfoundland are part of the "Outer Line", shown in white, as part of Africa broke away from the rest, and became part of North America, as the sliding collision continued. The Green Mountains of Vermont and the Gaspe peninsula of Quebec represent the "Inner Line", shown in blue.
The two "spines" of Long Island are part of this Outer Line. Nova Scotia and the peninsula formed by the Long Range Mountains in Newfoundland are a continuation of this line, collision mountains formed as the rest of what is now Africa slid across the part that had broken away to join what is now North America.
The two "spines" of Long Island are extensions of the Appalachian ridges across Pennsylvania.
You can see how, in the eastern portion of Newfoundland, the peninsulas formed by mountains are parallel to one another and the Long Range Mountains in the same way as the ridges throughout the Appalachians. The western peninsula of Newfoundland forms a line with the northern end of Nova Scotia.
As an interesting point, look at how the width of Nova Scotia closely resembles the short, broad peninsula on the Atlantic coast of South Africa, with Cape Town at it's southern end. This was also formed by a sliding tectonic collision very similar in nature to that which formed the Appalachians. The ridge formed by that collision is the Witwatersrand.
Notice the close parallel between the outer line of Nova Scotia and the inner line of the Gaspe Peninsula. But there is a section of the outer line missing from Cape Cod, in Massachusetts, to Nova Scotia.
What happened is simple. The missing section of the outer line broke away, and tectonically drifted until it came up against the inner line, the Green Mountains. This missing section is what we see today as the White Mountains of New Hampshire, and can explain why we have two close and parallel ranges of mountains.
How did two completely different mountain ranges, the Green Mountains (red line) and the White Mountains (white line) end up so close together? The Green Mountains are part of the Inner Line and continue to the Gaspe Peninsula (red dot). The White Mountains were part of the Outer Line that collapsed inward from between the white dots.
Notice how the coast of New England, from Massachusetts to New Brunswick, is a curve that is parallel to, and between, both the inner and outer lines, and also how the northward end of the high section of the White Mountains is adjacent to the southern end of Nova Scotia.
The peninsula of Cape Cod is also a continuation of the ridges of the Appalachians, as is Long Island. It got in the configuration that we see today by being "bent" as the missing section of the outer line broke away to form the White Mountains of New Hampshire.
Some of the most geologically significant terrain on earth is to be found in Nantucket Island, to the south of Cape Cod. It can easily be seen as two spines that form a curve. This was the crux of the bending, and breaking away, of the missing section of the outer line which are now the White Mountains. The island is actually a short section of one of the ridges of the Appalachians that was bent into the curve so that the seafloor in between was forced upward.
Cape Cod, Martha's Vineyard and, Nantucket are the end of the Inner Line, where part of it, from here to Nova Scotia, broke away. The broken piece of the Outer Line drifted inward, until it came up against the Inner Line. The piece of the Outer Line that broke away is now the White Mountains of New Hampshire, and the section of Inner Line that they came up against is the Green Mountains of Vermont.
To help understand this scenario, let's look at the opposite side of the continent. Canada extends further west than the U.S., due to the line of the tectonic plate boundary along the west coast. But this could well mean that Canada, including the heavy rock of the Canadian Shield, was once further east than it is now. It could also be that it was the disruption in the westward momentum that caused the missing section of the outer line to break away and move to the present position of the White Mountains.
I wrote that the reason for the Niagara Escarpment of North America being slanted downward toward the south is that it could have been pushed upward by the sliding tectonic collision of long ago, between what is now North America and what is now Africa, which formed the long mountain ranges and ridges of the Appalachian Mountains. This collision was described in detail in the posting "The Story Of North America", on this blog.
In that posting, I described how New York's Long Island is a result of that sliding collision. On a physical geography map, we can see that the two parallel "spines" underlying Long island are a continuation of the ridge system of the Appalachian Mountains.
I recently noticed that the sliding tectonic collision of land masses, which formed the Appalachian Mountain ranges and it's systems of ridges, also explains the geological foundation of Lake Erie.
During a recent visit to the magnificent Basilica of Our Lady of Victory in Lackawanna, New York, just south of Buffalo, I recalled the story of Father Nelson Baker insisting that there was a supply of natural gas to be found beneath the property. This took place before the basilica was built. Everyone was skeptical, particularly the drilling crew that arrived from Pennsylvania, but sure enough Father Baker was right.
We know that natural gas and oil forms in underground spaces that are formed when layers of rock are forced upward by tectonic collision. As it turns out, the basilica is indeed at the top of a wide "V" along South Park Avenue with the bottom of the V at Mile Strip Road. I pointed out, in "Stories Of The Great Lakes" that this "V" is a continuation of the main lengthwise axis of Lake Erie.
Since this "V" in the layers of rock along South Park Avenue in Lackawanna must have been formed by some tectonic collision for natural gas to be found there, and since it can be seen on a map to be a continuation of the lengthwise axis of Lake Erie, this must mean that Lake Erie exists in a long fold of rock layers that was formed by tectonic collision.
This "V" could not possibly be the result of glaciation, or pockets for natural gas to collect in would not exist underground. There is a glacial ridge, along which Ridge Road in Lackawanna is built, that intersects another glacial ridge along which South Park Avenue is built. The South Park Ridge is wide, but the drop off can be seen by looking to the west along side streets off South Park. But there are merely glacial deposits from sliding bergs of ice when the glaciers melted and broke up at the end of the last ice age, not structures in the underlying rock layers.
Now, back to the sliding tectonic collision between what is now North America and what is now Africa that formed the ranges and ridges of the Appalachian Mountains. One thing that has long caught my attention about Lake Erie is how it's southern (U.S.) shore forms such a straight line on a map between Cleveland and Buffalo. If we look at a physical geography map, we see that this straight line southern shore of Lake Erie is close to parallel with the ridges of the Appalachian Mountains.
The reason that it is slightly off parallel is due to the direction of the primary tectonic thrust that was forming the Appalachian Mountains. But this shows that the underlying geological foundation of Lake Erie is a long "V-shaped" fold of the rock layers, of which the same shape in Lackawanna along Mile Strip Road is a continuation. The underlying geology of Lake Erie is a result of the collision which formed the Appalachian Mountains. Soil and loose rock was excavated by glaciation during recent ice ages, forming the basin of Lake Erie.
This scenario also explains why the western (Toledo) end of Lake Erie is shallower than the Buffalo end. The western end of the lake is out of this line with the ridges of the Appalachian Mountains.
My explanation that the vast lowland centered around the Mississippi River was once seafloor that was pulled upward by the collision was later verified by the finding of a very ancient shark fossil in Webster County, Kentucky. This also explains why there would be recent earthquakes in Arkansas and Virginia, because even after all this time, the collision is actually still very slowly in progress.
What about another valley in the area formed by the V-form of the underlying rock layers? The Niagara Valley is the broad valley in the rock layers through which the Lower Niagara River flows. The lower Niagara River is at the low point along the bottom of the valley. This valley is aligned roughly north-south, so it is not in the correct alignment to have been formed directly by the Appalachian Collision, in the way that Lake Erie was. But it was formed by a break in the Niagara Escarpment due to uneven pressure on it as a result of the collision, which we will get to later in this posting.
THE HUMBER LINE
I have discovered an important geological line in eastern North America that I cannot see has ever before been pointed out.
The underlying geological foundation of Lake Erie is the fold in the rock layers that was created by the long-ago sliding collision which created the mountains and extensive ridges of the Appalachians.
On the map, we notice that the southern (U.S.) side of Lake Erie, from Cleveland to Buffalo, runs parallel to the ridges of the Appalachians to the southeast. This shows the relationship between the two, this rock fold was later excavated by moving glaciers during ice ages to form the lake.
Now, look at the great curve in the ridges of the Appalachians across central Pennsylvania. What we could call the focal point of the curve is the city of Harrisburg, the state capital of Pennsylvania. Harrisburg is not a major city and is not far from Lancaster, a center of Amish country, and York.
Next, what do you notice about Georgian Bay in Ontario? Like Lake Erie, Georgian Bay has a very clear lengthwise axis line through it. The really interesting thing is that the lengthwise axis lines of Lake Erie and Georgian Bay form a perfect right angle with one another. Another reason that Georgian Bay formed by the pressure of the Appalachian collision to the south is that the pressure was likely along an old line of magma emergence, as described in the posting on this blog "The Story Of Planet Earth".
A line through the long axis of Georgian Bay points directly toward Harrisburg, Pennsylvania, which we saw is the "focal point" of the curve of the Appalachians. This shows that the shape of Georgian Bay was affected by pressure from the Appalachian collision. The line is what I have named the "Humber Line", it passes through the Buffalo-Niagara region and Toronto, very much affecting the topography. Also notice that Lake Erie terminates at this line, at the city of Buffalo and the southern shore of Lake Erie, indicated by the red line, forms a perpendicular line with it.
The town of Boston, in western New York State, is in an elongated valley. This valley is part of the Humber Line and was formed by the changing direction of pressure of the tectonic collision which formed the Appalachians.
The straight line of the Buffalo Lake Erie waterfront, from Blasdell to downtown Buffalo, is a continuation of this straight line, the Humber Line.
The Humber Line continues as the straight-line southwestern shore of Canada's uninhabited Navy Island, in the Upper Niagara River.
The Humber Line then continues as the line of the whirlpool, in the lower Niagara River. This is the route of the former St. David's River, the counterpart to the present Niagara River, in the warm period before the last ice age. The route from the whirlpool to Lake Ontario follows the Humber Line. The Humber Line is shown by the yellow line. The falls are at center bottom.
On the other side of Lake Ontario, the Humber Line continues as Toronto's Humber Bay, hence it's name. This explains the drop in elevation in Toronto, going westward, along east-west streets west of downtown, such as Bloor Street.
The geological basis of Niagara Falls is not only the Niagara Escarpment but also the somewhat obscured fold in the rock layers that I named The Niagara Valley. The falls and the lower Niagara River are at the bottom of this valley.
The Niagara Valley is easier to see on the American side of Niagara Falls as a gradual slope that gets lower going westward. This is fairly easy to see if looking down the main east-west streets from around Hyde Park Boulevard westward. There is also a gradual southward slope, the result of the escarpment, but that is more clear in the LaSalle area of Niagara Falls, NY. Near the falls on the American side, it is easier to see the slope going westward. The falls happen to be close to the nadir of both the westward and southward slopes.
On the Canadian side, the Niagara Valley is mostly covered by the Niagara Falls Moraine, which was deposited by the glacier. It can best be seen on Thorold Stone Road, where the definite eastward slope can be easily seen. This Niagara Valley must be the result of the collision to the south which formed the Appalachians.
This line through the lengthwise axis of Georgian Bay to Harrisburg represents a shift in the primary direction of tectonic pressure that formed the Appalachians, and this line is the dividing line between the zones of primarily northwestward pressure and primarily northward pressure. The Niagara Valley is on the dividing line, and was created by the resulting uneven pressures on the Niagara Escarpment.
Now, on to Toronto. Residents of Toronto will be familiar with the significant change in elevation on east-west streets, such as Bloor Street, east of the High Park area. This is the eastern side of what is known as the Humber Valley, through which flows the Humber River. This Humber Valley, like the Niagara Valley and the falls, is the creation of this geological line that I am pointing out. Humber Bay, on the shore of the lake at the terminus of the Humber Valley, is not glacial in origin but is also the result of this line.
In naming this line, I realize that we could call it the "Harrisburg Line", or the "Niagara Line". But since Toronto is where the most people live, I decided that it is only fair to name it "The Humber Line".
The small bay on the shore of Toronto, between Toronto and Etobicoke, is known as Humber Bay. it is formed as part of the Humber Line, and is where the line meets the shore. High Park and the Humber Valley extend inland and are part of this line. To the east is the drop in elevation, going westward, on east-west streets such as Bloor Street.
The paradoxically-named "High Park" in Toronto is actually the lowest point in the city and is right on the Humber Line. The Humber Valley was a very important conduit for glacial movement during the ice ages, as described in "The Toronto Story" but it is definitely geological, rather than glacial, in origin. The other great valley in Toronto, the Don Valley to the east, is glacial in origin.
The Humber Line is the geological boundary that was formed when the sliding collision which formed the mountains and ridges of the Appalachians shifted direction. This shift in direction can best be seen in the great curve of the Appalachians across central Pennsylvania, with the focal point around the city of Harrisburg. This focal point is on an extension of the lengthwise axis of Georgian Bay, and that bay is the result of a glacial excavation of folds in the underlying rock created by the collision.
Lake Erie is also the result of a wide fold in the rock layers caused by the collision which created the Appalachians. Like Georgian Bay, Lake Erie has a clear lengthwise axis from Cleveland to Buffalo. The two axes form a right angle, and the Lake Erie axis terminates at the line through Georgian Bay to Harrisburg. This line, The Humber Line, passes directly through Niagara Falls and Toronto. It explains both the Niagara Valley, which hosts the falls, and the Humber Valley in Toronto.
Lake Erie's eastern terminus is the Humber Line. The lake was formed by folding of the rock strata by the pressure from the tectonic collision which formed the Appalachians. The section of the Humber Line which is the eastern terminus of Lake Erie shows in the following image as the straight line shore between Blasdell in the southeast to downtown Buffalo in the northeast.
As an added bonus, this explains why Toronto received such a jolt from the late summer 2011 earthquake centered in Virginia. It is because, even after all of these endless millions of years, the collision which formed the Appalachians is not quite completed, and Toronto lies directly on the Humber Line. I was in a suburb of Buffalo, at the intersection of the Humber and Lake Erie axis, and also received a very significant jolt from the quake.
BUFFALO'S INTERSECTION EARTHQUAKE
There was a relatively minor earthquake in the area of Buffalo, NY on February 6, 2023. The epicenter of the earthquake was determined to be below about where Mineral Springs Road intersects Indian Church Road, in West Seneca.
Let's have a look at two geological lines that we have seen here. Both of these lines are related to the formation of the mountains and ridges of the Appalachians, across the eastern U.S. and part of Canada. The sliding tectonic collision was between what was once North America and what was once Africa.
The collision front shifted direction, across Pennsylvania, because of the dense rock of the Canadian Shield, to the north. The pressure created a "V" in the rock strata, that later would fill with water and become Lake Erie. A center line, of geological shift, formed where the collision front shifted direction.
What is so interesting about this Buffalo earthquake is that it's epicenter is exactly where these two lines intersect. This means that, even though the Appalachians are old mountains, the tectonic collision that formed them is still going on.
This is the center line of the elongated Lake Erie, extending into the southern suburbs of Buffalo.
Image from Google Earth
This is the Humber Line that I found, the geological and physical geography changes along the center line of where the direction of the collision front changes during the formation of the Appalachians. You can see the elongated Lake Erie, formed by folds in the rock strata, at center left. Buffalo is at the eastern end of the lake. The white line is the border between the U.S. and Canada.
Image from Google Earth
The earthquake occurred exactly where these two lines intersect.
THE DETROIT-TOLEDO LINE
In "The Humber Line", we saw the effect of the sliding geological collision between what is now North America and what is now Africa as a line extending northwestward from the point at which the main thrust of the collision switched direction. We can easily see this shift of direction on a map in the directional alignment of the ridge systems of the Appalachians. The reason that North America and Africa are not still together is that they were split by volcanic activity of the Mid-Atlantic Ridge.
At the western end of Lake Erie, we see another straight line shore that was formed by pressure from the Appalachian Collision. This forms the lake's western terminus. I refer to this pressure line as the Detroit-Toledo Line.
The first rule of large-scale natural history is to look carefully for any lines or curves in the features of a physical geography map. The second rule is that, when you find something, look and see if something similar may have taken place elsewhere.
I have noticed another geological boundary line associated with the formation of the Appalachians. The Humber Line is the result of a shift in primary direction of the main thrust of the collision, likely resulting from the Canadian Shield to the north. This line, which I have named "The Detroit-Toledo Line", is the result of the beginning of the collision which formed the Appalachians.
Let's begin with the far western shore of Lake Erie, between Toledo and Detroit. Look at what a straight line it forms. Notice that this line continues to the north as the Detroit shore of Lake St. Clair. Now, if we jump across Lake Huron, we see that this same line reappears as the Canadian shore of Lake Huron northward from Clark Point, the most westward extension of the land into the lake.
The western shore terminus of Lake Erie continues as a nearly straight line in the western shore of the much-smaller Lake St. Clair.
Moving to the northeast, the line continues as the nearly straight-line northwestern shore of southern Ontario. The line also makes a deep "cut" into Ontario's Bruce Peninsula, which is actually a continuation of the Niagara Escarpment.
Finally the line continues on the other side of the Bruce Peninsula, which is actually the Niagara Escarpment as the long inlet from Georgian Bay to the town of Wiarton. This is where the Detroit-Toledo Line meets the Humber Line which, as we saw, bisects Georgian Bay.
Next, let's go back along this line in the other direction. Continue past Toledo, and keep going to the southwest. The Detroit-Toledo Line brings us to the area of Birmingham, Alabama. We can see on a map that this is where the Appalachians begin. So, we can definitely say that just as the Humber Line is the result of the change in direction of the Appalachians, the Detroit-Toledo Line is the result of their beginnings.
While it is clear that the Appalachian collision raised such features as the Allegheny Plateau of western Pennsylvania, there does not seem to be much written about the effects to the Appalachian collision to the north. I definitely cannot see that this Detroit-Toledo Line has ever been pointed out.
The collision which formed the Appalachians compressed the land in the direction of the collision, to the north-northwest. We saw in "The Geological Foundation Of Lake Erie" how the southern shore of the lake parallels the ridges of the Appalachians, and we can also see that the southern shore of Lake Ontario parallels it in the same way. This means that the drop in elevation going southward in Toronto is also the result of this collision.
Notice that along the southeastern side of the Detroit-Toledo Line from Toledo northward that water and land alternates. First, there is the water of Lake Erie. Then, there is land on the Canadian side, next there is the water of Lake St. Clair, then there is more land before the water of Lake Huron. Finally, there is the land north of Clark Point. This seems to be the result of the compression caused by the Appalachian collision.
If you want to see some more evidence of this line, look at the far western shore of Lake Erie in the satellite imagery. On the adjacent southern shore of the lake, it can clearly be seen that there is a wide area of shallow water just offshore. However in the straight line formed by the western shore north of Toledo, there is very little shallow area offshore. The water gets deep quickly as we move out into the lake.
This, combined with the straight line of this shore requires some special geological explanation and this Detroit-Toledo Line is it. The direction of the line, from southwest to northeast, matches the main thrust of the collision that produced the Appalachians.
The Detroit-Toledo Line is not all that we see in that area. There is also another straight line of the shore of Lake Erie, which meets the Detroit-Toledo Line, and runs from Toledo, where the two meet, southeast to past the city of Sandusky. This line, just like the Humber Line, can be seen to point southeastward to the "focal point" of the curve in the Appalachians to the south of Harrisburg, Pennsylvania.
Notice that the southwestern shore of Lake Erie also forms a nearly straight line, from Toledo past Sandusky. This line, just like the Humber Line, points directly to Harrisburg, Pennsylvania, which is the "focal point" of the curve of the Appalachians. The western end of Lake Erie forms a right angle just as does the southern shore with the Humber Line at the opposite end.
In "The Humber Line", we saw the effect of the sliding geological collision between what is now North America and what is now Africa as a line extending northwestward from the point at which the main thrust of the collision switched direction. We can easily see this shift of direction on a map in the directional alignment of the ridge systems of the Appalachians. The reason that North America and Africa are not still together is that they were split by volcanic activity of the Mid-Atlantic Ridge.
At the western end of Lake Erie, we see another straight line shore that was formed by pressure from the Appalachian Collision. This forms the lake's western terminus. I refer to this pressure line as the Detroit-Toledo Line.
The first rule of large-scale natural history is to look carefully for any lines or curves in the features of a physical geography map. The second rule is that, when you find something, look and see if something similar may have taken place elsewhere.
I have noticed another geological boundary line associated with the formation of the Appalachians. The Humber Line is the result of a shift in primary direction of the main thrust of the collision, likely resulting from the Canadian Shield to the north. This line, which I have named "The Detroit-Toledo Line", is the result of the beginning of the collision which formed the Appalachians.
Let's begin with the far western shore of Lake Erie, between Toledo and Detroit. Look at what a straight line it forms. Notice that this line continues to the north as the Detroit shore of Lake St. Clair. Now, if we jump across Lake Huron, we see that this same line reappears as the Canadian shore of Lake Huron northward from Clark Point, the most westward extension of the land into the lake.
The western shore terminus of Lake Erie continues as a nearly straight line in the western shore of the much-smaller Lake St. Clair.
Moving to the northeast, the line continues as the nearly straight-line northwestern shore of southern Ontario. The line also makes a deep "cut" into Ontario's Bruce Peninsula, which is actually a continuation of the Niagara Escarpment.
Finally the line continues on the other side of the Bruce Peninsula, which is actually the Niagara Escarpment as the long inlet from Georgian Bay to the town of Wiarton. This is where the Detroit-Toledo Line meets the Humber Line which, as we saw, bisects Georgian Bay.
Next, let's go back along this line in the other direction. Continue past Toledo, and keep going to the southwest. The Detroit-Toledo Line brings us to the area of Birmingham, Alabama. We can see on a map that this is where the Appalachians begin. So, we can definitely say that just as the Humber Line is the result of the change in direction of the Appalachians, the Detroit-Toledo Line is the result of their beginnings.
While it is clear that the Appalachian collision raised such features as the Allegheny Plateau of western Pennsylvania, there does not seem to be much written about the effects to the Appalachian collision to the north. I definitely cannot see that this Detroit-Toledo Line has ever been pointed out.
The collision which formed the Appalachians compressed the land in the direction of the collision, to the north-northwest. We saw in "The Geological Foundation Of Lake Erie" how the southern shore of the lake parallels the ridges of the Appalachians, and we can also see that the southern shore of Lake Ontario parallels it in the same way. This means that the drop in elevation going southward in Toronto is also the result of this collision.
Notice that along the southeastern side of the Detroit-Toledo Line from Toledo northward that water and land alternates. First, there is the water of Lake Erie. Then, there is land on the Canadian side, next there is the water of Lake St. Clair, then there is more land before the water of Lake Huron. Finally, there is the land north of Clark Point. This seems to be the result of the compression caused by the Appalachian collision.
If you want to see some more evidence of this line, look at the far western shore of Lake Erie in the satellite imagery. On the adjacent southern shore of the lake, it can clearly be seen that there is a wide area of shallow water just offshore. However in the straight line formed by the western shore north of Toledo, there is very little shallow area offshore. The water gets deep quickly as we move out into the lake.
This, combined with the straight line of this shore requires some special geological explanation and this Detroit-Toledo Line is it. The direction of the line, from southwest to northeast, matches the main thrust of the collision that produced the Appalachians.
The Detroit-Toledo Line is not all that we see in that area. There is also another straight line of the shore of Lake Erie, which meets the Detroit-Toledo Line, and runs from Toledo, where the two meet, southeast to past the city of Sandusky. This line, just like the Humber Line, can be seen to point southeastward to the "focal point" of the curve in the Appalachians to the south of Harrisburg, Pennsylvania.
Notice that the southwestern shore of Lake Erie also forms a nearly straight line, from Toledo past Sandusky. This line, just like the Humber Line, points directly to Harrisburg, Pennsylvania, which is the "focal point" of the curve of the Appalachians. The western end of Lake Erie forms a right angle just as does the southern shore with the Humber Line at the opposite end.
THE GEOMETRY OF LAKE ERIE
Lake Erie was formed by pressure from the Appalachian collision, to the south, against the Canadian Shield, to the north. It is actually defined by an isosceles right triangle.
The white dot is Harrisburg, which is the "focal point" of the curve of the Appalachians. The purple dot is Toledo and the red dot is the center of Georgian Bay. Pressure from the Appalachian collision tends to force rock strata upward so that it can be seen as a shoreline.
The right angle in the triangle is at Toledo. The yellow line leads to Harrisburg and forms one leg of the triangle. The white line is the Detroit-Toledo Line and forms the westernmost shore of Lake Erie. It also forms the western shore of Lake St. Clair, as shown by the white dot. The red dot is Toledo and the purple dot is Detroit.
The Detroit-Toledo Line goes on to form about half of the Lake Huron shore of Ontario, as shown by the red dots. The Detroit-Toledo Line is the other leg of the triangle.
The other side of the triangle, the hypotenuse, is the Humber Line. It forms the far eastern shore of Lake Erie, around Buffalo and Blasdell, and the center line of Lake Erie meets it at a right angle. The south shore of the lake closely parallels it's center line.
This triangle is actually bisected by the center line of Lake Erie.
Lake Appalachian and Appalachian Bay are two bodies of water that you will not find on a map. But I felt it necessary to summarize earlier postings about the role of the long-ago tectonic collision between what is now North America and what is now Africa, resulting in the system of ridges and mountains in the eastern U.S., known as the Appalachians, in forming Lake Erie and Georgian Bay.
These two bodies of water are the result of wide folds in the underlying rock layers as a result of the tectonic collision which formed the Appalachians.
Just look at the shores of Lake Erie. The southern shore, from Cleveland to Buffalo, forms a virtually perfect straight line. This line, as well as the long axis of the lake, parallels the ridges of the Appalachians to the south and east, as pointed out in "The Geological Foundation Of Lake Erie".
The basin which is now filled with the water of Lake Erie was formed by folds in the underlying rock layers resulting from the collision which formed the Appalachians. As explained in that section, this is why the Buffalo end of Lake Erie is deeper than the Toledo end. The western end of the lake is out of the lines parallel to the Appalachians.
There is another line associated with the Appalachians, and the tectonic collision which formed them. In the section in this posting, "The Detroit-Toledo Line", we saw that there is an easily visible geological line extending from the beginnings of the Appalachians, in northern Alabama, continuing to the far western shore of Lake Erie, and then continuing from the northwestern shore of southern Ontario from Point Clark to the Niagara Escarpment. This is the result, once again, of the compression of the underlying rock layers during the collision which formed the Appalachians.
The important point, concerning Lake Erie, is how it's far western shore from Toledo to Detroit is actually the geological line formed by the beginning of the Appalachians. You can see in the satellite imagery that the lake gets deep quickly as we go outward from the shore, but that is not true of the southern shore.
The Niagara Escarpment is easily visible on a map as the arc from southern Ontario as the Bruce Peninsula and Manitoulin Island, forming northern Michigan to the Door Peninsula in Wisconsin.
There is the other geological line associated with the formation of the Appalachians, "The Humber Line" in the section of this posting by that name. While the Detroit-Toledo Line was formed by the beginning of the Appalachians, this line was formed by it's change in direction as it met what we refer to as the Canadian Shield, the layer of heavy rock that underlies approximately the eastern half of Canada.
As pointed out in "The Humber Line", the change in direction forms a great curve in the ridges and mountains of the Appalachians. The focal point of this curve is around the city of Harrisburg, in Pennsylvania. This curve can easily be seen on any physical geography map.
If we look at the long axis of Georgian Bay, in Ontario, and continue it in a straight line to the southeast, we see that it leads right to the "focal point" of the great curve in the Appalachians.
(To those in the Buffalo area, you can see the long axis of the lake continuing inland as the broad V in the rock layers along South Park Avenue, with the low point at Mile Strip Road).
Maybe we should rename Lake Erie "Lake Appalachian", or maybe "Geometry Lake" since so much about it consist of geometric lines.
We saw that the lengthwise axis of Georgian Bay, in Ontario, is in line with the focal point of the Appalachians. Notice also that it is where these two lines, the Humber Line and the Detroit-Toledo line, meet. The meeting of these two geological lines associated with the Appalachian collision formed a low area in the underlying rock layers that is today filled with the water of Georgian Bay. Although it is likely true that another reason for the formation of Georgian Bay is that it was once a line of magma emergence, as described in the posting on this blog "The Story Of Planet Earth".
Maybe we should rename it "Appalachian Bay".
Lake Ontario also has a relation to the Appalachians. It would seem that Lake Erie would have continued parallel to the curve great formed by the Appalachians, if not for the presence of the Niagara Escarpment. The folding of the rock layers, which produced the higher and lower areas can be easily seen in the city of Toronto to the east of the Humber Valley, for which the Humber Line is named. The elevation gets steadily lower from the northern reaches of the city right down to Lake Ontario.
THE ERIE-ONTARIO LINE
There have been the previously unidentified geological lines associated with the long-ago tectonic collision between what is now North America and what is now Africa, which formed the system of mountains and ridges across the eastern U.S., known as the Appalachians.
One such line extends from the area of origin of the Appalachians in Alabama and extends north northeast to form the far western shore of Lake Erie and a section of the Lake Huron shoreline of Ontario. This I named "The Detroit-Toledo Line".
The Appalachians extend in a roughly straight line from the Atlanta-northern Alabama area to the northeast until they undergo a great curve in western Pennsylvania. The "focal point" of this curve is around the city of Harrisburg, the state capital of Pennsylvania. We can see that the vast Georgian Bay in Ontario, an extension of Lake Huron, is oval-shaped and has a long axis through it. If we extend the line of this axis to the southeast, we find that it leads directly to Harrisburg.
This line I named "The Humber Line". We can see that the line also extends beyond Harrisburg to the southeast, the segment of the Humber Line that I named "The Susquehanna Line", in a posting of that name, because the Susquehanna River conforms to this line exactly.
The Humber Line is very significant because it passes right through Buffalo, Niagara Falls and Toronto. In Buffalo, the line explains the straight far eastern shore section of Lake Erie from the southern suburb of Blasdell to downtown Buffalo and also the change in elevation of the underlying rock layers in Buffalo from east to west as can be easily seen along the Kensington and Scajaquada Expressways. The drop in elevation along the Humber Line is in the Parkside Neighborhood, and I named this section of the Humber Line "The Parkside Line".
In Toronto, the Humber Line is very prominent as the eastern side of the Humber Valley which creates the sharp change in elevation along main streets such as Bloor Street. The Humber Line continues to form the long axis of Georgian Bay, which exists as a low area in the rock layers because that is where the two lines meet.
There is yet another geological line that I would like to point out as having originated as a part of the Appalachian system.
First, trace the curve of the Appalachians across West Virginia and Pennsylvania.
Next, look at the line of the northern (Canadian) shore of Lake Erie and how it curves until the curve changes around the town of Port Stanley. Now, go over to the northern shore of Lake Ontario just east of Hamilton. Notice how the original curve picks back up here, and continues all along the Canadian shore of Lake Ontario.
The southwestern Canadian shore of Lake Erie forms a curve with the Canadian (northern) shore of Lake Ontario, but the curve is interrupted by the Niagara Peninsula. This curve is parallel to the curve of the Appalachians, with the focal point of Harrisburg, and was formed by the same tectonic pressures.
The zone where the curve is interrupted is mostly the land known as the Niagara Peninsula. This is a creation of the Niagara Escarpment, which was there before this segment of the Appalachian collision. The escarpment is not a fault itself, but was caused by uneven erosion due to a hard layer of top limestone. The tectonic collision did cause a disruption in the Niagara Escarpment, along the Humber Line, as the Niagara Valley in which the falls is located.
The curve of the Appalachians across West Virginia and Pennsylvania is nearly perfectly parallel to this curve of what we will call "The Erie-Ontario Line" with the exception, of course, of the lands around the Niagara Escarpment. Thus, we can be certain that these two of the Great Lakes would be one curving lake parallel to the Appalachians if it were not for the Niagara Escarpment.
Both of these Great Lakes are the result of folds in the rock layers caused by the collision. In Toronto, east of the Humber Line, there is a steady increase in elevation from the lakeshore northward to around Steeles Avenue. This is an example of the vast folds in the rock layers due to the collision that formed Lakes Erie and Ontario.
THE SUSQUEHANNA LINE
The mountains and ridges across this area, known as the Appalachians, were formed long ago by the tectonic collision between what is now North America and what is now Africa. The reason for the complex system of ridges in the Appalachians is that the collision was more of a sliding collision than a frontal collision.
The Appalachians curve across Pennsylvania so that the primary directional alignment of the mountains and ridges shifts from southwest-northeast to east-west. The "focal point" of this curve is approximately the city of Harrisburg, the state capital of Pennsylvania. This can easily be seen on any physical geography map.
One of the two geological lines that I identified is what I termed "The Humber Line", named for the valley and the drop in elevation in Toronto that results from it. If we look at the long axis of Georgian Bay, in Ontario, and follow that axis in a straight line to the southeast, we find that it leads right to Harrisburg. This could not possibly be a coincidence. The changing direction of pressure resulting from the shift in direction of the tectonic collision front which formed the Appalachians created Georgian Bay. Although it is likely that another factor in the formation of Georgian Bay is that it was once a line of magma emergence, as described in the posting on this blog "The Story Of Planet Earth".
If we follow the Humber line from Harrisburg to the long axis of Georgian Bay, we see that it passes right through Toronto, Niagara Falls and, Buffalo. I pointed out that the drop in elevation in the middle of metropolitan Toronto, representing the east side of the Humber Valley and seen along streets such as Bloor Street west of downtown, is a manifestation of the Humber Line as the layers of rock east of the line were forced upward relative to those west of the line due to the more direct tectonic pressure as the shift in direction of the collision that formed the Appalachians took place.
The lower river at Niagara actually exists within the local valley that I pointed out in the posting "The Niagara Valley" on the Niagara natural history blog. This broad valley is largely obscured by the glacial moraine that was deposited in the area, and is seen today as the high ground by the falls on the Canadian side. But if we look closely we see that on the American side of Niagara Falls, the ground gets lower as we go west, and on the Canadian side particularly on Thorold Stone Road, the ground gets lower as we go east.
Thus, we have the Niagara Valley that hosts the lower river and the falls. The Humber Line passes right through the area and explains this valley as resulting from the uneven pressure on the Niagara Escarpment due to the tectonic collision which formed the Appalachians.
In the city of Buffalo, I pointed out what I called "The Parkside Line". This is another manifestation of the Humber Line as seen in the change in elevation around Buffalo's Parkside neighborhood, in a way roughly similar to that in Toronto but of lesser difference in elevation. This refers to the sudden change in the elevation of the underlying rock layers in Buffalo, most noticeable in the Parkside neighborhood just east of Delaware Park. The higher elevation moving east is also noticeable on the Scajaquada Expressway (Route 198) near the eastern end of Delaware Park.
The far eastern shore of Lake Erie yields yet another manifestation of the Humber Line in the straight line section of the shore from the area of downtown Buffalo to the southern suburb of Blasdell. This is also a creation of the shift in the Appalachian collision. The lake shore just adjacent to Mile Strip Road is the most eastward point of the lake, and is where two important geological lines that are related to the Appalachians meet. One line is the long center axis of Lake Erie, and the other is the Humber Line which forms the straight-line section of the Lake Erie shore from this point northward.
The other line in this system of geological lines that I pointed out is "The Detroit-Toledo Line". This line runs from the area in the Alabama around which the Appalachians begin through Toledo and Detroit. We saw how the stretch of the far western shore of Lake Erie follows this line, just as the far eastern shore follows the Humber Line. The place where the two lines meet is the resulting low area in the rock which, filled with water, is known as Georgian Bay.
All of Lake Erie is very much a creation of the Appalachian collision and the resulting folds in the rock. The lake has a long axis, much like that of Georgian Bay, which terminates at the Humber Line which it meets just south of Buffalo. The long axis of Lake Erie can be seen on a map to parallel the ridges of the Appalachians to the south, as can the straight-line shore of the lake from Cleveland to Buffalo. Residents of the south Buffalo area can see the long axis of the lake as folds in the rock layers extending inland as the broad V on South Park Avenue with the bottom at Milestrip Road.
Now, let me show you what I have recently found about this line that is so interesting. We saw that the Humber Line extends from the focal point of the curve in the Appalachians, at Harrisburg, northwestward through the long axis of Georgian Bay.
But if we now continue the Humber Line through Harrisburg, and continue to the southeast, we find that the course of the Susquehanna River conforms precisely to this line. How else can it be explained why the Susquehanna River curves all over northeastern Pennsylvania, but then conforms to a nearly perfect straight line after it passes Harrisburg which we saw was the "focal point" of the great curve in the mountains and ridges of the Appalachians.
Let's call the section of the Humber Line, on the other side of Harrisburg, "The Susquehanna Line". This makes sense because while all of my writings about this line have thus far been about the land on the other side of the Appalachians, the land to the south and east of the collision front must have been affected in a similar way and we should expect to find manifestations of it there.
One other interesting thing that I recently noticed concerning the Appalachians concerns Florida. The peninsula of Florida is actually surrounded by wide areas of shallow water that is about twice as large as the state itself. This is especially true on the western, Gulf of Mexico side of Florida.
Florida consists of former sea floor that was forced upward by the Appalachian collision. Just as the rear cars on a train still have momentum if the trains comes to a stop due to a sudden collision. Notice how Florida seems to be the geological directional opposite of the Allegheny Plateau in Pennsylvania, which was also forced upward by the collision.
The thing that is striking about Florida is that if we follow the Detroit-Toledo Line southward until we go past the area of Alabama in which the Appalachians begin, we see that it leads right to the westward limit of the continental shelf, the wide area of shallow water, around Florida. This definitely makes it look as if the scenario of Florida's formation is correct.
THE APPALACHIAN COLLISION AND THE NIAGARA ESCARPMENT
I would like to demonstrate just how easy it is to discover things that have never before been noticed. There is a feature of the underlying geology in the Niagara Falls area that may be virtually unique in the world, and which determines the shape of the Niagara River both the lower river below the falls and the upper river above it.
This escarpment is a kind of cliff with a height of maybe 30-40 meters in places. It extends a long way and can be seen on any map of northeastern North America as the Door Peninsula, which separates Green Bay from Lake Michigan in Wisconsin. It extends eastward from there in a great curve as the "backbone" of northern Michigan, Manitoulin Island and the Bruce Peninsula which separate Georgian Bay from Lake Huron. The escarpment continues across southern Ontario, changes direction at Hamilton, and finally terminates at Rochester in the U.S.
The Niagara Escarpment is the product of uneven erosion of the limestone layers over millions of years, due to an especially resistant top layer, it is believed to be at least 200 million years old.
On the U.S. side at Niagara the Niagara Escarpment is seen as a dark green line on the map which runs roughly parallel to the shore of Lake Ontario, which is the body of water at the top of the map. The green is from the trees which grow on the escarpment.
Now, look at the Canadian side of the Niagara Escarpment and you will see that the escarpment changes direction to the southwest of the city of St. Catharines. The escarpment forms a kind of a V-shape with Effingham in the crux. Long-time readers will recall that this is the site of the former glacial waterfall that we saw in the posting "The St. Catharines Falls", on the Niagara natural history blog.
By the way, the north-south line of water that you can see just east of St. Catharines is the Welland Canal, built to link Lakes Erie and Ontario, and is not a part of the natural history.
Now, look at the town of Pelham-Ridgeville, to the south of St. Catharines. The town of Fonthill is there also. You can see Effingham where this break of the Escarpment is. There is a ridge that extends westward from these towns along Route 20. Unfortunately, the ridge does not show up in this satellite imagery but Route 20 can be seen, which is built atop the ridge. I wrote about this ridge in "The St. Catharines Falls".
I do not know if the ridge has a name, let's call it the "Fonthill Ridge". This ridge is actually on the top of the escarpment, and is aligned roughly parallel to the escarpment. The ridge's highest point is just adjacent to Pelham-Ridgeville and Fonthill. The ridge continues for several km westward, toward Hamilton, before it gradually fades out. There is a spectacular view from certain stretches of the ridge when looking southward, in the general direction of Lake Erie.
One thing that is for certain is that this ridge is not glacial in origin. It is solid rock that actually rises from the top of the escarpment. The question is: what on earth would cause such a ridge to form where it does, and why does the ridge end abruptly at it's highest point at the eastern end of the ridge near Pelham-Ridgeville and Fonthill?
Yet something caught my attention, that the ridge abruptly terminates at it's highest point and that this point is adjacent to the point at which the escarpment can be seen to change direction, to the southwest of St. Catharines at Short Hills Provincial Park. This seemed to me to be worth further investigation.
I went to this area to look for special effects of the "break" in the Escarpment that might not show up well in the satellite imagery or on a map. The ridge along Route 20 is shown in white. Moving eastward the ridge reaches it's highest point and then abruptly ends when it is even with the crux of the "break in the Escarpment, shown by the white dot. The Escarpment is easy to see because of the dark green trees growing along it. The "break" in the Escarpment is not far from Brock University. The upper red dot is St. Catharines. The lower red dot is Welland. The purple dot is Fonthill. The yellow dot is Thorold.
Next let's review the Humber Line. The system of mountains and ridges that comprises the Appalachians, across the eastern U.S. was formed by a long and sliding tectonic collision between what is now North America and what is now Africa. The line of the collision undergoes a great curve across Pennsylvania that can easily be seen on any physical geography map. The "focal point" of this curve is at Harrisburg, the state capital of Pennsylvania.
Georgian Bay, to the north in Ontario is also the product of the Appalachian collision and it is likely also that the bay formed due to pressure from the Appalachian collision along an old line of magma emergence. I noticed that there is a long axis to Georgian Bay and that if we continue the line of this axis to the southeast, it leads directly to Harrisburg which is the focal point of the curve. This "Humber Line", as I named it, goes directly through Buffalo, Niagara Falls and, Toronto. I described the manifestations of the line in all three places. In Toronto, it is seen as the change in elevation on main east-west streets west of downtown, such as Bloor Street. This is the west side of the Humber Valley through Toronto, hence the name of the line.
Georgian Bay, to the north in Ontario is also the product of the Appalachian collision and it is likely also that the bay formed due to pressure from the Appalachian collision along an old line of magma emergence. I noticed that there is a long axis to Georgian Bay and that if we continue the line of this axis to the southeast, it leads directly to Harrisburg which is the focal point of the curve. This "Humber Line", as I named it, goes directly through Buffalo, Niagara Falls and, Toronto. I described the manifestations of the line in all three places. In Toronto, it is seen as the change in elevation on main east-west streets west of downtown, such as Bloor Street. This is the west side of the Humber Valley through Toronto, hence the name of the line.
The Humber Line clearly explains both the ridge atop the escarpment, and the change in direction of the escarpment adjacent to it. The Humber Line is where the primary direction of the great tectonic collision changes direction from primarily northwestward to primarily northward. The escarpment is aligned in such a way that it would bear the brunt of the tectonic pressure from the gradual collision which was forming the Appalachians. But the full pressure would be exerted on the escarpment only east of the Humber Line, because that is where the direction of pressure changes.
Several km west of the Humber Line, the tremendous tectonic pressure builds and is enough to force up a rocky ridge out of the escarpment, but the pressure is not enough here to actually move the escarpment. As we move eastward, toward the Humber Line, the pressure becomes greater and greater against the escarpment, and it raises the rocky ridge on the escarpment higher and higher.
Finally, as we reach a point just west of the towns of Pelham-Ridgeville and Fonthill, the tectonic pressure is so great that it actually shifts the escarpment. With the pressure going into this, it no longer goes into raising the rocky ridge and that is why it terminates here, adjacent to the point where the escarpment changes direction near Effingham.
Now, notice the direction of the lower Niagara River below the falls in the satellite imagery. This narrow section of the river is at the bottom of the broad valley in the rock layers that I identified as "The Niagara Valley", which is described in detail in the following section.
This is also along the zone of the Humber Line, notice that the section of the lower river immediately below the falls is roughly parallel to the section of the escarpment that has been shifted just east of the change in direction at Short Hills Provincial Park. To the east of the point where the tectonic collision shifted the escarpment, the pressure went into creating this valley rather than raising the rocky ridge.
Notice how the lower Niagara River, below the falls and which forms the U.S.-Canada border, is exactly parallel to the eastward arm of the "V" formed by the Niagara Escarpment at the point where it "breaks" southwest of St. Catharines, due to the pressure from the Appalachian collision. That is because it was the collision which formed the Niagara Valley, of which the lower Niagara River here flows along the base of the valley. The two parallel lines are just to the left of each red line. The section of the Lower Niagara River is on the right. These two parallel lines are at a right angle to the Humber Line.
This scenario is not complicated. To the west of the Humber Line, there was not enough force from the tectonic collision which formed the Appalachians to shift the escarpment, so the pressure raised the ridge atop the escarpment. To the east, when the point was reached where there was enough force to shift the escarpment, the ridge abruptly ended at it's highest point. The escarpment had it's direction shifted, and from that point along the Humber Line the force went into creating the Niagara Valley rather than raising the ridge. The Niagara Valley, with the lower Niagara River below the falls along it's bottom, was created instead of a ridge because the adjacent section of the escarpment had been pushed further away by the tectonic force, as can easily be seen on the map.
This scenario explains still more. Like a broken stick, the escarpment which was created by a hard layer of cap stone is naturally weakest at the point of breakage. Notice that this is where the great erosion of the escarpment has taken place that was described in "The St. Catharines Falls". Glacial meltwater eroded away the escarpment here, at the ends of the ice ages, forming large but temporary waterfalls like nowhere else along the entire escarpment. It is this break in the escarpment, caused by the tremendous pressure of the Appalachian collision, that explains why this took place here. The dark green area on the map around Effingham at Short Hills Provincial Park represents this area of erosion in the escarpment.
This scenario should provide a valuable insight into how a powerful tectonic force interacts with a well-established feature of the landscape. The geological lines that I have pointed out as having resulted from the long-ago sliding tectonic collision between what is now North America and what is now Africa, which formed the complex system of ridges and mountains in the eastern U.S. known as the Appalachians, simply mean that the pressure was greater on one side of the line than the other so that the rock strata on the higher-pressure side may be raised or compressed or that the entire terrain might be shifted.
SUMMARY OF HUMBER LINE
Has anyone in the Buffalo NY-Niagara area ever noticed something interesting on a map of the area? I have already pointed out that the straight-line far eastern shore of Lake Erie from downtown Buffalo to around the southern suburb of Blasdell is part of the Humber Line.
Has anyone in the Buffalo NY-Niagara area ever noticed something interesting on a map of the area? I have already pointed out that the straight-line far eastern shore of Lake Erie from downtown Buffalo to around the southern suburb of Blasdell is part of the Humber Line.
The Appalachians undergo a great curve across Pennsylvania, due to a change in direction of the sliding collision which formed them. The focal point of this collision is around Harrisburg, the state capital of Pennsylvania.
If we look at Georgian Bay in Ontario, we see that it has a long axis, and that if we continue the line of the axis to the southeast it brings us directly to Harrisburg. This far eastern shore of Lake Erie is directly on, and is part of the Humber Line, because as the primary direction of pressure from the Appalachian tectonic collision shifted from northwestward to northward, it formed a line of changing pressure which we see today as this Humber Line.
If we look at Georgian Bay in Ontario, we see that it has a long axis, and that if we continue the line of the axis to the southeast it brings us directly to Harrisburg. This far eastern shore of Lake Erie is directly on, and is part of the Humber Line, because as the primary direction of pressure from the Appalachian tectonic collision shifted from northwestward to northward, it formed a line of changing pressure which we see today as this Humber Line.
The Canadian island in the upper Niagara River, known as Navy Island. This island has been uninhabited for decades, but once had farms and orchards and was proposed as the site of the United Nations. Navy Island is irregularly-shaped. The striking thing about Navy Island is how it's southwestern shore, facing the mainland Canadian shore, forms a perfect straight line. Not only that, but this straight line of it's shore continues the line of the far eastern shore of Lake Erie that I pointed out.
Furthermore I observed that if we continue this line to the northwest, the section of the lower Niagara River approaching the whirlpool where the rapids are located, also follows this line. In fact, if we remember the St. David's River which was the manifestation of the Niagara River in the warm period before the last ice age, we see that it actually followed this line right up to the point where it met the Niagara Escarpment at the Ontario village of St. David's, hence the name of the river.
The axis of the lower Niagara River through the rapids and the whirlpool to the Ontario village of St. David's is the Humber Line and this was the route of the St. David's River which was the counterpart of the present Niagara River in the warm period before the last ice age.
You can see on the map the course of this former St. David's River. It extended from what is now the whirlpool to the gap in the escarpment, which can be seen at St. David's. While driving on the Queen Elizabeth Way (QEW) past St. David's, there is a drop in the level of the highway as it crosses what was once this river. The St. David's River was filled in by dirt and debris by the moving glaciers of the last ice age.
But the present Niagara River, which carved it's way back from the Niagara Escarpment at Lewiston-Queenston, occupies part of the course of this former river from about where the Whirlpool Bridge is located around to the whirlpool, and the resulting change in course of the Niagara River can easily be seen on a map.
We can see, on any map, how the Susquehanna River in Pennsylvania changes course to conform to the Humber line on the opposite side of Harrisburg, to the southeast. There is a section about the Susquehanna River in this posting. The same thing took place here, the St. David's River before the last ice age encountered and followed the Humber Line.
Another thing stands out about the Humber Line in this area. There was the Niagara Valley which we saw above as having been formed by the movement of part of the escarpment as a result of tectonic pressure from the Appalachian collision. The lower Niagara River is at the low point of this valley, which makes it easy to follow on the map. By the way, Upper Niagara River means above the falls and Lower Niagara River means below the falls.
The Niagara Valley can be seen at ground level in that the terrain gets lower as we go west on the American side in the area of the falls, but on the Canadian side it gets lower as we go east. The Niagara Valley is mostly covered on the Canadian side by the Niagara Falls Moraine, which was a vast amount of soil deposited by glacial movement and best seen as the high ground on the Canadian side by the falls, but can be seen on Thorold Stone Road in that the terrain gets lower going eastward.
The thing that stands out about the Niagara Valley is that it terminates around the Humber Line, and is at a right angle to it and is only found to the southwest of it and not to the northeast. This demonstrates that, as I have pointed out, this valley in the rock strata of the area is the creation of the tectonic collision. This is because, northeast of the Humber Line, the pressure would be more directly perpendicular to the Niagara Escarpment, and would likely simply cause it to move, rather than to break as along the Niagara Valley.
This is why the landscape of the western part of Niagara Falls, NY, meaning La Salle, is tilted toward the southwest. The southward tilt is due to the incline shape of the Niagara Escarpment. The westward tilt is due to this Niagara Valley, which was formed south and west of the Humber Line by the collision which formed the Appalachians.
The reason that the Appalachian collision underwent a change of direction is the Canadian Shield, which is the dense layer of rock underlying approximately the eastern half of Canada. As the direction of tectonic pressure shifted to primarily northward, from northwestward, the pressure on the Niagara Escarpment grew greater as we go eastward. The defining line of pressure change is the Humber Line that I pointed out. But there are actually three zones of pressure change that we can see in the results on the Niagara area landscape.
The first is the raising of the rocky ridge adjacent to the escarpment that runs west from the Ontario towns of Fonthill, Ridgeville and, Pelham.East of this point, a section of the escarpment shifted northward due to the tectonic pressure and the result of this is the Niagara Valley. West of this point, the pressure was enough to raise the ridge but not enough to shift the escarpment itself. The place at which the pressure reached the point where it was enough to actually move the land under the escarpment is Short Hills Provincial Park, southwest of St. Catharines.
But when we move eastward to the Humber Line, the Niagara Valley ends and the escarpment shifts still more. The Humber Line is the line along which the Niagara River flows toward the whirlpool, and continues to the gap in the escarpment at St. David's. There is no ridge or valley, formed by the pressure, east of this point because those only form when there is pressure against the escarpment but not enough to shift it.
The Lyell-Johnson Ridge is, of course, so important to the natural history of the area because it was when the falls cut through this ridge that the former Lake Tonawanda began to drain and all that remains of it today is the broad upper Niagara River. I will not go into detail here about this former lake, but have written about it extensively on the Niagara natural history blog.
Aside from this ridge, there is yet another effect of the Appalachian collision to be seen in the rock strata of downtown Niagara Falls, NY. Just east of 1st Street, on Buffalo Avenue and around the traffic circle at the intersection of Rainbow Boulevard, it can be seen that there is an elevated level in the rock strata which forms a kind of low plateau. Both this and the Lyell-Johnson Ridge are just west of the Humber Line, on the other side of the Humber Line the pressure was great enough to move the escarpment itself still more and so there were no more special effects, such as these and the ridge west of Fonthill, to the south of the escarpment.
I also think that the low ridge in Niagara Falls, Canada along Stanley Avenue from Bridge to Morrison Streets is the result of an upward thrust in the rock strata resulting from this tectonic pressure.
We can thus see that there is a kind of transition zone in the tectonic pressure as we approach the Humber Line itself. First, to the west, the pressure raised the rocky ridge west of the towns of Fonthill, Ridgeville and, Pelham but not enough to move the escarpment. Then, moving eastward, the pressure became great enough to shift the escarpment somewhat and also to create the Niagara Valley, the Lyell-Johnson Ridge and the plateau in downtown Niagara Falls, NY. Finally, as we go eastward and cross the Humber Line, the pressure was great enough to simply move all of the terrain under the escarpment with no more special effects, such as the ridges, as the pressure built against the escarpment.
This transition zone can be seen further north, in Toronto. The Humber Valley actually is the transition zone. The Humber Line is the east side of the valley, marked by the change in elevation on east-west streets west of downtown, such as Bloor Street. The Humber Valley can be seen on a map as Humber Bay, which is a continuation of the valley, off Lake Ontario. The Humber Valley, including Humber Bay, is where the low terrain of Lake Ontario was pushed back by the tectonic pressure. The rise in the terrain east of the line is caused by the increased pressure as the front of the collision shifted so that the pressure was northward.
I get the impression that Mimico Creek, just west of Humber Bay, is the western boundary of the pressure transition zone. It is parallel to what the Humber Line would be and it has an extensive delta where it empties into Lake Ontario, which the other creeks in the area do not. This delta on Mimico Creek shows that it was the route for glacial ice, which we know tends to follow such geological lines in the rock layers.
THE NIAGARA VALLEY
I have found what must be the next most important factor in the formation of Niagara Falls after the escarpment. I have named it the Niagara Valley. It is a wide valley in the underlying rock layers aligned roughly north-south. This valley is very old and is not easily visible today since it has been largely filled in by the Niagara Falls Moraine, the high ground on the Canadian side by the falls, and carved up by the Niagara River.
But this valley was the underlying factor in all that happened at Niagara Falls. This posting may actually be considered as the most important one about Niagara natural history because all of the other Niagara postings are about the effects of flowing water and moving glacial ice, but this one is about the underlying geology which shapes all else.
The straight-line section of the Lower Niagara River from the ninety degree angle at the falls north northeastward to where Bridge Street on the Canadian side and the Whirlpool Bridge is located runs along the low line of the Niagara Valley, which extends westward into Canada and eastward into the U.S.
The place that this old valley is most visible today is on Thorold Stone Rd. in Niagara Falls, Canada. If you go eastward, toward the river, on that road from the intersection with Dorchester Rd., you will reach a high point and then begin a long and gradual drop that reaches all the way down to the present Niagara Gorge. This is the western side of the valley.
A few miles to the southeast, on the American side, anywhere near the falls the southwestward slope of the rock strata is unmistakable. From the intersection of John B. Daly Blvd. and Rainbow Blvd., if you look westward along Rainbow Blvd. toward the falls, you will see another long and gradual drop, this time in the opposite direction. This is the eastern side of the valley. This valley was not carved by water at all but is along the underlying rock strata.
Another glimpse of the western side of the valley can be seen in the way that Lundy's Lane climbs higher west of the intersection with Portage Rd. in Niagara Falls, Canada. Although here, the valley has been covered by the Niagara Falls Moraine, which was deposited by a later glacier.
The upper rapids above the falls begin at the eastern edge of the slope of the Niagara Valley in the Niagara River. We know that these rapids are created by the same slope in the underlying rock that we see along Rainbow Blvd.
A large amount of soil and loose rock was deposited in the valley by an ice age glacier. This is what we now refer to as the Niagara Falls Moraine, and is seen as the high ground on the Canadian side of the falls, including the slope of Clifton Hill. The eastward part of the moraine was pushed in to it's present position by the falls by sliding fragments of the last glacier as it melted and broke apart. This moraine, and the Niagara River that made a northward turn when it collided with it, are the reasons that the valley is so difficult to discern today.
FORMATION OF THE NIAGARA VALLEY
To understand how the Niagara Valley, and thus the falls as they are today, formed we must look at the big picture of North America. The Appalachian system of mountains in the eastern USA was formed by the collision between what is now Africa and what is now North America. This long system includes the Allegheny, Blue Ridge, Catskill, Adirondack, Green and, White Mountains. It also includes the system of ridges in Tennessee and Kentucky that parallels it.
The Appalachians are much older than the Rockies in the western part of the continent so the collision that formed them happened long before the collision of the entire western hemisphere with the Pacific Plate. The collision that formed the Appalachians also forced up layers of rock strata adjacent to the mountains such as the Allegheny Plateau in New York and Pennsylvania.
Now, back to Niagara Falls and the underlying Niagara Valley. This valley includes the slant in the underlying rock strata to the southwest above the falls at about 20 feet (6 meters) per mile (1.5 km). This is what gives us the upper rapids and is why the water above the falls is deeper on the Canadian side.
The underlying Niagara Valley is most obvious here in it's contrast with the opposite slope of Thorold Stone Road. The southward element of the slope in the underlying rock above the falls is not a part of the Niagara Valley. The southward slope is a property of the escarpment itself and is visible in the numbered streets in the LaSalle section of Niagara Falls if we look south from Niagara Falls Blvd. along the 70s numbered streets. This direct southward slope, with no westward slope element, means that the 70s streets, in Niagara Falls NY, are located eastward beyond the Niagara Valley.
The fracturing of the rock strata, as the pressure of the Appalachian collision met the Niagara Escarpment, was not perfectly neat. The resulting southwestward slope, the southward element of the slope is the result of the sawtooth shape of the escarpment and the westward element is the result of the Niagara Valley, is greatest near the falls, on the American side. But lesser westward slopes, the result of the Appalachian collision forming the Niagara Valley, can be seen well to the east in the landscape of Niagara Falls, NY.
There is actually a subtle boundary region in Niagara Falls, NY where the primary underlying slope becomes southwestward instead of southward. If we look east on John Ave. from 66th St., we can see in the surface of the street the beginning of the westward slope that extends down to the falls. The subtle westward slope can also be seen in the parking lot of Home Depot on Builder's Way. The westward slope of Girard Avenue, between the Interstate 190 and 56th Street, is just barely perceptible. Closer in the direction of the falls, if we look westward along Pine Avenue from Hyde Park Boulevard, the westward slope becomes somewhat more perceptible. On Main Street, near the area of the falls, the westward slope of the Niagara Valley is very definite. Further north, the westward slope of Ontario Avenue is another place where we see the Niagara Valley.
The point of this is that this section of the lower Niagara River, below the falls, is aligned from south southwest to north northeast along exactly the same angle as are the Appalachian Mountains and ridges before the great curve of the collision front across Pennsylvania. Remember that this section of the river flows along the low line of the Niagara Valley. This can be easily seen if we look at a map of eastern North America alongside a map of Niagara Falls.
Thus, it is my conclusion that the continental collision which resulted in the Appalachian Mountains exerted tremendous force that caused a fracture in the rock strata at a distance and resulted in the formation of the Niagara Valley.
The Niagara Escarpment broke in two places, one on each side of it. The most clear break is the one on the side of the escarpment away from the collision front, at Short Hills Provincial Park near St. Catharines. On the opposite side of the escarpment is the break which forms the Niagara Valley. This break caused a shift in the terrain at right angles to the break at the Niagara Valley, which is why the Upper Niagara River shore of the city of Niagara Falls, NY forms a continuous line with the axis of the Decew Lakes near St. Catharines and the "breaking point" of the escarpment on it's opposite side. This is also why the Upper and Lower Niagara Rivers, above and below the falls, seems to form a perfect right angle. This should not seem unusual at all as the Niagara Region is really not far from the Allegheny Plateau that was created by the collision.
Notice how the U.S. shore of the Upper Niagara River (red dot), which is the remnant of a former lake, forms a straight line with the "breaking point" of the Niagara Escarpment near St. Catharines (purple dot).
The river from the Horseshoe Falls to the Whirlpool Bridge represents the low point of the Niagara Valley. Water always seeks the lowest point and this is why this stretch of the lower river follows the course it does today. To get to the falls, water in the uppoer rapids is flowing down the east side of the Niagara Valley. Once the river passes the Whirlpool Bridge, it is past the end of the valley and it's course diverges.
THE HUMBER LINE AND THE NIAGARA VALLEY
Let's now turn to the place where the straight line section of the lower Niagara River curves to the west, along what is known as the Lower Niagara Rapids, toward the whirlpool in the Niagara River.
Remember we saw how the geographical features created by this tectonic collision revolve around what I defined as the Humber Line, named for the valley across Toronto where it is most visible. The Humber Line is the line that I noticed extends from the "focal point" of the curve of the Appalachians, around the city of Harrisburg in Pennsylvania, through the long axis of the elongated Georgian Bay in Ontario. In the opposite direction from Harrisburg the Susquehanna River, which meanders around northeastern Pennsylvania before reaching Harrisburg, suddenly adheres to a straight line flow along the Humber Line after passing Harrisburg.
If we follow the line of the Humber Line through the general area of the Niagara River, we see that it forms the straight line of the easternmost shore of Lake Erie, from Blasdell to downtown Buffalo. We then see that the Humber Line forms the straight line of the southwestern shore of Navy Island, the uninhabited Canadian island in the upper Niagara River. Notice that this shoreline is a perfect continuation of the easternmost shore of Lake Erie.
We then see that the Humber Line intersects the Niagara Valley. In fact, the Niagara Valley ends at the Humber Line, where the lower Niagara River ceases to be a straight line and curves along the lower rapids. The Humber Line then appears along the northern shore of Lake Ontario at Humber Bay, in Toronto. The well-known drop in elevation along east-west streets to the west of downtown Toronto, such as Bloor Street, represents how the land is elevated on the east side of the Humber Line due to the difference in pressure as the collision front of the Appalachians shifted direction across Pennsylvania.
(Note-I don't want to digress too much here, but the reason that this shift caused by the change in direction of the Appalachian collision front is so well-defined along this line is that the Humber Line was actually once a longitudinal line of magma emergence when the north pole was migrating across Canada, from it's former position at what is now the Great Basin of the western U.S. to it's present position, as described in "The Story of Planet Earth").
The reason that the Niagara Valley ends at the Humber Line, at the beginning of the Lower Rapids, is that the break in the structure of the Niagara Escarpment which formed the Niagara Valley only took place to the west of the Humber Line. To the west of the Humber Line, the pressure on the land from the south increased as the collision front of the Appalachians changed direction as it continued eastward. To the east of the Humber Line, the force was enough to simply shift the Niagara Escarpment to the north.
This meant that there were fewer special effects on the land, such as this Niagara Valley, than there were to the east of the Humber Line. To the west of the Humber Line, there was not quite enough force to shift the entire escarpment so the force went into creating various special effects. The shifting of the escarpment itself created a special effect, that can easily be seen on a map, as the smooth bulge of land extending out into Lake Ontario between the cities of St. Catharines and Rochester, as we see in the following section "The Niagara Escarpment Bulge And The Appalachian Collision".
Another such "special effect" of the pressure against the Niagara Escarpment west of the Humber Line is the rocky ridge which extends to the west of the town of Fonthill, Ontario. Just as the Niagara Valley only continues until it meets the Humber Line, this rocky ridge only continues eastward until it meets the "breaking point" of the escarpment, which is at Short Hills Provincial Park, near St. Catharines. The Break in the escarpment, caused by building pressure along the Appalachian collision front to the south, should logically have taken place right at the Humber Line. The reason that it didn't is that the rock strata has a structure of it's own and is not "fluid". So, the break in the escarpment took place just west of the Humber Line, at Short Hills Provincial Park to the southwest of St. Catharines.
There have been two rivers across the Niagara area, from Lake Erie to Ontario, the present Niagara River and the St. David's River in the warm period before the last ice age. The St. David's River flowed from what is now Dufferin Islands, on the Canadian shore of the Niagara River, across what is now Goat Island. The sections that are common to both rivers are the lower rapids and the whirlpool.
The St. David's River flowed through what is now the whirlpool and met the escarpment at the Ontario village of St. David's, hence it's name. Along the QEW Highway (Queen Elizabeth Way), west of Stanley Avenue, there is a wide area of a lower elevation adjacent to the village of St. David's which is a remnant of this former river before it was mostly filled in by soil and loose rock carried along by the glaciers of the last ice age.
But notice that this St. David's River followed the Humber Line exactly from the point where it encountered the line in what is now downtown Niagara Falls, NY. The St. David's River route from the whirlpool at the village of St. David's is right along the Humber Line. The St. David's River followed the Humber Line, the lower Niagara River follows the Niagara Valley which ends at the Humber Line. The whirlpool formed when the Niagara River's flow and falls excavated the loose fill of the former St. David's River, and this directed the Niagara River in another direction so that it does not follow the course of the Humber Line.
The yellow line is a segment of the Humber Line, along which the former St. David's River flowed, in the warm period before the last ice age. The segment of the Lower Niagara River that is below and perpendicular to it is the nadir of the Niagara Valley.
RIDGES WITHIN THE NIAGARA VALLEY
One other notable feature of the area is the so-called Lyell-Johnson Ridge. This is a low, rounded ridge that cuts directly across the valley. When the falls, eroding it's way southward, about 3,500 years ago cut through the high ground at Hubbard's Point, Lake Tonawanda began to drain and Niagara Falls as we know it began to take shape.
RIDGES WITHIN THE NIAGARA VALLEY
One other notable feature of the area is the so-called Lyell-Johnson Ridge. This is a low, rounded ridge that cuts directly across the valley. When the falls, eroding it's way southward, about 3,500 years ago cut through the high ground at Hubbard's Point, Lake Tonawanda began to drain and Niagara Falls as we know it began to take shape.
The red line is the Lyell Johnson Ridge. Sir Charles Lyell visited Niagara Falls and discovered the former St. David's River. When the falls cut through this ridge Lake Tonawanda began to drain. The wide Upper Niagara River today is a remnant of this lake. In the second image, from Google Street View, notice the drop in elevation southward along Military Road in the Town of Niagara. This was once under the water in the lake.
This ridge is visible along River Rd. in Niagara Falls, Canada extending south from the Whirlpool Bridge with the high point at Eastwood Cr. It is also visible on the American side on Whirlpool St., as you pass Spruce and Cedar Avenues.
Another such ridge can be seen in Niagara Falls, Canada on Stanley Ave. If you head south from Bridge St., you will go over the same type of low and rounded ridge.
These two ridges are part of the rock structure, and are not glacial in origin. They can in no way be explained in terms of the Niagara River. But, if we consider the Humber Line, it is easy to see that both ridges are immediately west of it and, like the Niagara Valley which they are within, terminate before the Humber Line. There are no such ridges to the east of the Humber Line. These two ridges are explained as a part of this scenario with the Appalachian collision. They are reeves in the rock strata that were formed by the same pressures as the Niagara Valley, and are congruent to the rocky ridge west of Fonthill.
(Note-this Lyell-Johnson Ridge also helps explain why the embayment at Dufferin Islands, that I have discussed in other Niagara natural history blog postings such as "Dufferin Islands And The Former St. David's River", is where it is. The embayment is a former whirlpool from the previous warm inter-glacial period. It is located as far west as it can be due to the underlying slope of the rock strata along the eastern side of the Niagara Valley but it could not be any further west or else it would be too low for water from it to be able to cross the Lyell-Johnson Ridge on it's way northward to the escarpment).
One other such ridge, which is within the Niagara Valley and formed by the same pressure from the Appalachian collision as it, is what some natural historians refer to as "Niagara Island". This is not an actual island but is an area of a little higher elevation in the rock strata right downtown in Niagara Falls, NY near the falls. The large hotel with a curved front brick facade, John's Hotel Niagara, is built on this elevation. The reason for referring to it as an island is that it was briefly an island when the former Lake Tonawanda drained after the falls, cutting it's way backward to it's present location, cut through the Lyell-Johnson Ridge about 3500 years ago.
As a final thought about this Niagara Valley, why does the Niagara River meet the Niagara Escarpment where it does? If we go eastward in Niagara County, the escarpment gets lower in elevation. We know that the former Lake Tonawanda, which was a product of the gradual southward slope of the rock strata of the escarpment, extended eastward to the area of Rochester. So, why didn't the Niagara River form further east where the escarpment was lower? The answer is that the flow followed this Niagara Valley, even though the escarpment is higher in elevation where it is located, there is no other logical answer.
THE NIAGARA ESCARPMENT BULGE AND THE APPALACHIAN COLLISION
I would like to discuss an effect of the sliding tectonic collision between what is now North America and what is now Africa on the Niagara area as the bulge of land which extends outward into Lake Ontario from St. Catharines to Rochester. The Niagara River passes through this bulge of land, on it's way to empty into Lake Ontario. Only about 5% of this Niagara area bulge of land is in Canada, but that area is probably Canada's most important grape-growing regions.
This bulge of land into Lake Ontario from the Niagara region is on a map or the satellite imagery. Let's call it the Niagara Escarpment Bulge. It is the broad bulge of land extending outward into Lake Ontario from St. Catharines to Rochester.
This bulge of land corresponds exactly to the Niagara Escarpment, which changes direction at St. Catharines and fades out around Rochester. If you look closely at the satellite imagery, you can see the Niagara Escarpment as a dark line running approximately parallel to, and about 7-10 km south of, the Lake Ontario shore. The dark line is actually the trees growing on the slope of the escarpment. The "breaking point" of the escarpment, where it was "bent" so that the direction changed, can be seen as the dark area of dense tree growth just to the southwest of the city of St. Catharines. This is actually Short Hills Provincial Park.
The white line in the following image is Lake Ontario and the yellow line is Lake Erie. The peak of the Escarpment Bulge is the white dot. You can see the line of the Escarpment on which are the two yellow dots. The red dot is Buffalo. The purple dot is Toronto. The green dot is Rochester.
The Niagara Escarpment may look something like an earthquake fault line, but it isn't. The escarpment was actually formed by uneven erosion of the underlying limestone layers, and is a formation known as a cuesta. Limestone gradually forms at the bottoms of warm and shallow seas from the bodies of microscopic creatures. Sandstones and slate forms in a way similar to limestone, but from grains of sand rather than the bodies of living things. When there is some tectonic movement of landmasses, driven by the rotation of the earth, these layers of limestone may be forced upward to become dry land.
Limestone does not last forever, it erodes away over millions of years. What happened in the Great Lakes region of North America is something special. Ordinary limestone is calcium carbonate, but a layer of limestone formed that was magnesium carbonate instead. This layer of rock was much more resistant to erosion than ordinary limestone, and it protected the layers below from erosion. The result is the Niagara Escarpment, which is about 200 million years old. The cap layer of magnesium carbonate on the escarpment is known as Lockport Dolostone, named for the city on the escarpment.
As to why this upper layer of magnesium carbonate formed, see the posting on the Niagara Natural History blog "The Niagara Escarpment And The Meteorite".
The sliding tectonic collision between what is now North America and what is now Africa created the ridge systems of the Appalachians, as well as shaping the basins of Lakes Erie and Ontario. You may notice that the Canadian shores of both of these lakes form a continuous curve except for the Niagara Peninsula, the northern support of which is the Niagara Escarpment.
As we will see in the the next section of this posting, "The Very Special Escarpments Of Buffalo And Fort Erie", it was tectonic pressure from this collision which "broke" the escarpment and pushed the section to the east of Short Hills Provincial Park northward. The direction of the Appalachian collision curved due to the Canadian Shield to the north, the dense layer of rock underlying the eastern half of Canada. As the collision front shifted eastward across Pennsylvania, pressure built up against the Niagara Escarpment to the north. We saw that the pressure raised the rocky ridge that runs west of the Ontario town of Fonthill. (This ridge can be seen by observing the drop in elevation to the south on Effingham Street from the intersection with Highway 20 West).
With the pressure increasing as the direction of the collision shifted to north from northwest, the pressure on the Niagara Escarpment reached the point where the escarpment literally broke, and east from that point shifted northward. The "breaking point" is at Short Hills Provincial Park, that is where the escarpment changes direction and is also where the rocky ridge extending westward from Fonthill ends.
The bulge of land extending outward into Lake Ontario between St. Catharines, near Short Hills Provincial Park which was the breaking point of the escarpment, and Rochester, where the escarpment fades out, can be explained simply as the shift of the escarpment to the north due to pressure on the land mass from the Appalachian collision across Pennsylvania. This forced layers of sandstone immediately in front of the shifting escarpment upward, even as the larger scale result of the pressure from the collision was a folding of the rock strata to form the basin of Lake Ontario.
Pressure from the Appalachian collision to the south actually caused the escarpment to break in two places, one on each side. The most clear break is at Short Hills Provincial Park, adjacent to St. Catharines, on the side of the escarpment facing away from the Appalachian collision. But not far away, on the opposite side of the escarpment, is the break which formed the Niagara Valley. The Niagara Valley is a collapse of the rock strata to form a broad valley, the lower Niagara River below the falls later found it's way through this valley.
This collapse of the rock strata to form the Niagara Valley caused a corresponding shift in the adjacent rock layers in a perpendicular direction. Notice the shoreline of the city of Niagara Falls, NY forms a rough straight line that is perpendicular to the straight line section of the lower Niagara River. We know that this straight line section of the lower Niagara River is along the base of the Niagara Valley, so it is logical that this right angle be related to the formation of the Niagara Valley.
Notice how the shores of Niagara Falls, NY, the city on the right, on the broad upper Niagara River and the narrow lower Niagara River, form a right angle. That is due to the pressure of the Appalachian collision. The falls have been eroding their way southward from the Escarpment since the end of the last ice age and it is just by chance that they are at the intersection of this right angle now.
Notice again that the axis of the Decew Lakes, on the escarpment above St. Catharines and leading directly to the "breaking point" of the escarpment at Short Hills Provincial Park forms a line with the Upper Niagara River shoreline of Niagara Falls, NY, shown by the red and purple dots, and is also perpendicular to the straight line section of the lower Niagara River. This was caused by the shift in adjacent rock layers in the perpendicular direction as the collapse of the rock strata which formed the Niagara Valley took place, and explains why the Upper Niagara River is exactly perpendicular to the Lower Niagara River with the falls now located where the two meet.
This answers a question about the Niagara area that has never been answered. Notice again in the satellite imagery how the straight line section of the narrow Lower Niagara River, immediately below the falls, comes to an end and the river goes into a curve. The straight line is where the river follows the bottom of the Niagara Valley. The beginning of the curve is where the Niagara Valley, caused by the collapse of the rock strata in a break in the escarpment, comes to it's northern end. The water here is seen as a white line, instead of the usual blue-green color of the water. The reason for the color change is that the white represents the Lower Rapids, where the water is flowing extremely fast and the turbulence mixes in air to give the water it's white color. The white areas in the Upper River, just above the falls, are the Upper Rapids where the water flows toward the falls down the eastern side of the Niagara Valley.
The reason for the Lower Rapids is that there is a slope in the rock strata underground that cannot be seen from the surface. The collapse of the rock strata which formed the Niagara Valley, due to the break in the escarpment caused by the northward pressure of the Appalachian collision, extends only as far as the beginning of this underground slope in the rock strata that forms the Lower rapids. The conclusion seems clear, that the end of the Niagara Valley and the beginning of the Lower Rapids, about where the Whirlpool Bridge is located, was once where the escarpment stood until it was pushed northward to where it sends now by pressure from the Appalachian collision to the south. The rock strata which collapsed, to form the Niagara Valley, was only in the zone where the escarpment had stood previously. Much of the stress on the escarpment was relieved by it's shift northward, and this is why the collapse which formed the Niagara Valley does not continue all the way to where the escarpment stands today, at Lewiston-Queenston.
Notice that the white line of the lower rapids in the Niagara River begins at a point that is directly level, due east, of the breaking point, which is the crux of the "V", where the escarpment "breaks" southwest of St. Catharines. This southern beginning of the white line of the lower rapids is where the Niagara Valley ends, and is also on the Humber Line. The red line in the following image is an east-west line from the "break" in the Niagara Escarpment near St Catharines.
The reason for the curve in the river at the Lower Rapids is that it is following the route of the former St. David's River, which was the version of the Niagara River from the warm period before the last ice age. Notice that the curve leads to the whirlpool and, if we continue the line, to the break in the escarpment at the village of St. David's, hence the name of the former river which was filled in by soil and debris carried by the glaciers of the ice age but was readily excavated by the river after the end of the last ice age because it was easier to flow through than the solid rock layers all around.
The Humber Line that I noticed with regard to this posting is the discernible line on the satellite imagery which formed when the pressure from the Appalachian collision front to the south shifted from mostly northwestward to mostly northward. I named it for the side of the Humber Valley in Toronto. The Humber Line does not go right through the "breaking point" of the escarpment, but is not far to the east of it. The Humber Line does pass right across the northern end of the Niagara Valley.
The reason is that the Niagara Valley begins at the end of the southward slope of the escarpment at it's southern end, and continues to the Humber Line at it's northern end. The termination of the Niagara Valley at the Humber Line shows both the significance of the Humber Line with regard to the displacement of the Niagara Escarpment by the pressure from the shifting collision front of the Appalachians to the south, and that the Niagara Valley was formed as a result of the pressure on the escarpment from the Appalachian Collision. The escarpment was, in effect, being "stretched" to the west of the Humber Line, as opposed to the entire structure of the escarpment just being shifted to the north, so that something had to give way and that something was the collapse of the rock strata which formed the Niagara Valley.
At ground level in Toronto, the Humber Line can be seen as the drop in elevation on east-west streets west of downtown, such as Bloor Street In Buffalo, it can be seen as "The Parkside Line" as described in the section by that name. There are a number of places in the satellite imagery that the Humber Line can be seen. The far eastern shore of Lake Erie from Blasdell through downtown Buffalo forms a straight line with the southwestern shore of Navy Island, in the Niagara River near Niagara Falls. On the other side of Blasdell, the line continues as the Boston Valley in which the town of Boston, NY is located.
The Boston Valley resulted from uneven tectonic pressure on it's opposite sides as the direction of the thrust from the Appalachian collision shifted. Just as when the Niagara Valley formed, this caused pressure on the rock layers in a perpendicular direction which also caused a shift due to different pressures, and this is what formed western New York's scenic Zoar Valley which is perpendicular to and runs southwestward from the southeastern end of the Boston Valley. The Zoar Valley extends between the towns of Gowanda and Springville.
The Niagara Escarpment may look something like an earthquake fault line, but it isn't. The escarpment was actually formed by uneven erosion of the underlying limestone layers, and is a formation known as a cuesta. Limestone gradually forms at the bottoms of warm and shallow seas from the bodies of microscopic creatures. Sandstones and slate forms in a way similar to limestone, but from grains of sand rather than the bodies of living things. When there is some tectonic movement of landmasses, driven by the rotation of the earth, these layers of limestone may be forced upward to become dry land.
Limestone does not last forever, it erodes away over millions of years. What happened in the Great Lakes region of North America is something special. Ordinary limestone is calcium carbonate, but a layer of limestone formed that was magnesium carbonate instead. This layer of rock was much more resistant to erosion than ordinary limestone, and it protected the layers below from erosion. The result is the Niagara Escarpment, which is about 200 million years old. The cap layer of magnesium carbonate on the escarpment is known as Lockport Dolostone, named for the city on the escarpment.
As to why this upper layer of magnesium carbonate formed, see the posting on the Niagara Natural History blog "The Niagara Escarpment And The Meteorite".
The sliding tectonic collision between what is now North America and what is now Africa created the ridge systems of the Appalachians, as well as shaping the basins of Lakes Erie and Ontario. You may notice that the Canadian shores of both of these lakes form a continuous curve except for the Niagara Peninsula, the northern support of which is the Niagara Escarpment.
As we will see in the the next section of this posting, "The Very Special Escarpments Of Buffalo And Fort Erie", it was tectonic pressure from this collision which "broke" the escarpment and pushed the section to the east of Short Hills Provincial Park northward. The direction of the Appalachian collision curved due to the Canadian Shield to the north, the dense layer of rock underlying the eastern half of Canada. As the collision front shifted eastward across Pennsylvania, pressure built up against the Niagara Escarpment to the north. We saw that the pressure raised the rocky ridge that runs west of the Ontario town of Fonthill. (This ridge can be seen by observing the drop in elevation to the south on Effingham Street from the intersection with Highway 20 West).
With the pressure increasing as the direction of the collision shifted to north from northwest, the pressure on the Niagara Escarpment reached the point where the escarpment literally broke, and east from that point shifted northward. The "breaking point" is at Short Hills Provincial Park, that is where the escarpment changes direction and is also where the rocky ridge extending westward from Fonthill ends.
The bulge of land extending outward into Lake Ontario between St. Catharines, near Short Hills Provincial Park which was the breaking point of the escarpment, and Rochester, where the escarpment fades out, can be explained simply as the shift of the escarpment to the north due to pressure on the land mass from the Appalachian collision across Pennsylvania. This forced layers of sandstone immediately in front of the shifting escarpment upward, even as the larger scale result of the pressure from the collision was a folding of the rock strata to form the basin of Lake Ontario.
Pressure from the Appalachian collision to the south actually caused the escarpment to break in two places, one on each side. The most clear break is at Short Hills Provincial Park, adjacent to St. Catharines, on the side of the escarpment facing away from the Appalachian collision. But not far away, on the opposite side of the escarpment, is the break which formed the Niagara Valley. The Niagara Valley is a collapse of the rock strata to form a broad valley, the lower Niagara River below the falls later found it's way through this valley.
This collapse of the rock strata to form the Niagara Valley caused a corresponding shift in the adjacent rock layers in a perpendicular direction. Notice the shoreline of the city of Niagara Falls, NY forms a rough straight line that is perpendicular to the straight line section of the lower Niagara River. We know that this straight line section of the lower Niagara River is along the base of the Niagara Valley, so it is logical that this right angle be related to the formation of the Niagara Valley.
Notice how the shores of Niagara Falls, NY, the city on the right, on the broad upper Niagara River and the narrow lower Niagara River, form a right angle. That is due to the pressure of the Appalachian collision. The falls have been eroding their way southward from the Escarpment since the end of the last ice age and it is just by chance that they are at the intersection of this right angle now.
Notice again that the axis of the Decew Lakes, on the escarpment above St. Catharines and leading directly to the "breaking point" of the escarpment at Short Hills Provincial Park forms a line with the Upper Niagara River shoreline of Niagara Falls, NY, shown by the red and purple dots, and is also perpendicular to the straight line section of the lower Niagara River. This was caused by the shift in adjacent rock layers in the perpendicular direction as the collapse of the rock strata which formed the Niagara Valley took place, and explains why the Upper Niagara River is exactly perpendicular to the Lower Niagara River with the falls now located where the two meet.
This answers a question about the Niagara area that has never been answered. Notice again in the satellite imagery how the straight line section of the narrow Lower Niagara River, immediately below the falls, comes to an end and the river goes into a curve. The straight line is where the river follows the bottom of the Niagara Valley. The beginning of the curve is where the Niagara Valley, caused by the collapse of the rock strata in a break in the escarpment, comes to it's northern end. The water here is seen as a white line, instead of the usual blue-green color of the water. The reason for the color change is that the white represents the Lower Rapids, where the water is flowing extremely fast and the turbulence mixes in air to give the water it's white color. The white areas in the Upper River, just above the falls, are the Upper Rapids where the water flows toward the falls down the eastern side of the Niagara Valley.
The reason for the Lower Rapids is that there is a slope in the rock strata underground that cannot be seen from the surface. The collapse of the rock strata which formed the Niagara Valley, due to the break in the escarpment caused by the northward pressure of the Appalachian collision, extends only as far as the beginning of this underground slope in the rock strata that forms the Lower rapids. The conclusion seems clear, that the end of the Niagara Valley and the beginning of the Lower Rapids, about where the Whirlpool Bridge is located, was once where the escarpment stood until it was pushed northward to where it sends now by pressure from the Appalachian collision to the south. The rock strata which collapsed, to form the Niagara Valley, was only in the zone where the escarpment had stood previously. Much of the stress on the escarpment was relieved by it's shift northward, and this is why the collapse which formed the Niagara Valley does not continue all the way to where the escarpment stands today, at Lewiston-Queenston.
Notice that the white line of the lower rapids in the Niagara River begins at a point that is directly level, due east, of the breaking point, which is the crux of the "V", where the escarpment "breaks" southwest of St. Catharines. This southern beginning of the white line of the lower rapids is where the Niagara Valley ends, and is also on the Humber Line. The red line in the following image is an east-west line from the "break" in the Niagara Escarpment near St Catharines.
The reason for the curve in the river at the Lower Rapids is that it is following the route of the former St. David's River, which was the version of the Niagara River from the warm period before the last ice age. Notice that the curve leads to the whirlpool and, if we continue the line, to the break in the escarpment at the village of St. David's, hence the name of the former river which was filled in by soil and debris carried by the glaciers of the ice age but was readily excavated by the river after the end of the last ice age because it was easier to flow through than the solid rock layers all around.
The Humber Line that I noticed with regard to this posting is the discernible line on the satellite imagery which formed when the pressure from the Appalachian collision front to the south shifted from mostly northwestward to mostly northward. I named it for the side of the Humber Valley in Toronto. The Humber Line does not go right through the "breaking point" of the escarpment, but is not far to the east of it. The Humber Line does pass right across the northern end of the Niagara Valley.
The reason is that the Niagara Valley begins at the end of the southward slope of the escarpment at it's southern end, and continues to the Humber Line at it's northern end. The termination of the Niagara Valley at the Humber Line shows both the significance of the Humber Line with regard to the displacement of the Niagara Escarpment by the pressure from the shifting collision front of the Appalachians to the south, and that the Niagara Valley was formed as a result of the pressure on the escarpment from the Appalachian Collision. The escarpment was, in effect, being "stretched" to the west of the Humber Line, as opposed to the entire structure of the escarpment just being shifted to the north, so that something had to give way and that something was the collapse of the rock strata which formed the Niagara Valley.
At ground level in Toronto, the Humber Line can be seen as the drop in elevation on east-west streets west of downtown, such as Bloor Street In Buffalo, it can be seen as "The Parkside Line" as described in the section by that name. There are a number of places in the satellite imagery that the Humber Line can be seen. The far eastern shore of Lake Erie from Blasdell through downtown Buffalo forms a straight line with the southwestern shore of Navy Island, in the Niagara River near Niagara Falls. On the other side of Blasdell, the line continues as the Boston Valley in which the town of Boston, NY is located.
The Boston Valley resulted from uneven tectonic pressure on it's opposite sides as the direction of the thrust from the Appalachian collision shifted. Just as when the Niagara Valley formed, this caused pressure on the rock layers in a perpendicular direction which also caused a shift due to different pressures, and this is what formed western New York's scenic Zoar Valley which is perpendicular to and runs southwestward from the southeastern end of the Boston Valley. The Zoar Valley extends between the towns of Gowanda and Springville.
In western New York State how do two broad valleys end up at a right angle to each other? Zoar Valley (red line) runs parallel to the collision front of the Appalachians while Boston Valley (purple line) is along the Humber Line. The two valleys intersect at Springville.
This process was far from as smooth as I am making it sound here, and all of this took many millions of years. Land masses and rock strata are not very fluid. That is why we have earthquakes, pressure build up and the land slips suddenly instead of flowing smoothly as if it were a fluid. The division of the northward pressure of the Appalachian collision to the south was not smooth either as the collision from progressed across Pennsylvania, and the pressure direction shifted from northwestward to northward. There is a valley that is roughly parallel to the Boston Valley extending southward from East Aurora, along Route 16, and which formed in the same way as the Boston Valley.
The very pronounced valleys to the east of here, such as Letchworth State Park which run in a different direction, do not fit this scenario. These were formed with the Finger Lakes of central New York State, and are from glacial ice thrusts, during the Ice Ages, which were channeled between the barriers of the Niagara Escarpment and the Adirondack Mountains to the east.
Let's now look at the eastern end of Lake Ontario. Notice the large peninsular land mass on the Canadian side that differs sharply from the otherwise fairly smooth coastline of Lake Ontario. This is Prince Edward County.
Notice also that the western limit of this peninsular land mass is due north of the eastern end of the Niagara Escarpment Bulge, at Rochester. This is no coincidence. The mass of the escarpment being forced northward by the tectonic pressure of the sliding Appalachian collision across Pennsylvania "smoothed out" the northward pressure from there so that the Canadian shore of Lake Ontario is smooth to the north of the Niagara Escarpment. and it's outward bulge. But east of the end of the escarpment, that is not the case. There is the much more shapeless peninsular land mass of eastern Ontario's Prince Edward County. The white dot in the following image is the Niagara Escarpment Bulge. The red dot is Prince Edward County.
In another topic, the lines across this peninsular land mass are perfectly aligned to be a continuation of the line of magma emergence which comprises the St. Lawrence Valley. This St. Lawrence emergence line is aligned just right to be a longitudinal line of emergence from when the north pole was what is now the Great Basin of the western U.S. Continued in the opposite direction, out to sea, this line can be seen as forming the trench in the relatively shallow sea between Greenland and Iceland. Lake St. Clair is also on this line, and may the result of residual magma emergence below pulling the land apart to form a lower area.
There is an escarpment which passes through the area on an east-west line, known as the Onondaga Escarpment. There is an article about it and a map on Wikipedia. This escarpment is nowhere near as high as the Niagara Escarpment and is probably unnoticed by most people since it's slopes are often difficult to distinguish from the common slopes created by the movement of glacial ice during the ice ages.
The Niagara Peninsula of Ontario, the land east of Hamilton to the Niagara River which is the U.S. border, is formed and defined by the Niagara Escarpment on it's north side and this Onondaga Escarpment on it's south side. These escarpments are the reason that the shorelines of Lakes Erie and Ontario do not form a continuous curve parallel to the Appalachians, or indeed why the two are not a single lake.
The upper white line is the Niagara Escarpment and the lower white line is the Onondaga Escarpment.
The Onondaga Escarpment extends east-west and has a steep side facing north, with a sloping side facing south. The Niagara Escarpment is structured the same way, but much higher in elevation. The Niagara Escarpment is not any kind of fault line, but formed by uneven erosion over millions of years. This type of land form is known as a cuesta.
The Niagara Escarpment is layers of limestone, which erodes over long periods of time. Caves form in limestone when the rock is gradually dissolved by flowing water. The stalactites that form on the ceilings of caves, like icicles, are from dissolved limestone recrystallizing.
The Niagara Escarpment exists because a layer of very durable limestone formed, which shielded the layers below from erosion. Ordinary limestone is calcium carbonate but magnesium was introduced, probably by a meteorite that landed in a body of water, so that the durable top layer is magnesium carbonate. There is a posting on the Niagara Natural History blog, "The Niagara Escarpment And The Meteorite". I presume that the Onondaga Escarpment formed in a similar way.
The Onondaga Escarpment can be seen on Transit Road, near the intersection of Sheridan Drive. This is the northward steep side. The sloping side can be seen in the long and slow drop in elevation southward toward Lancaster. The steep northward side of the escarpment can also be seen just north of Main Street, along Harlem Road, in Williamsville.
On Main Street in north Buffalo, to the north of East Amherst Street, the terrain on Main Street is seen as much higher to the east and lower to the west. Main Street gets continuously higher as we go north from Hertel Avenue, until we reach University Heights upon which the South Campus of the University of Buffalo is located.
Going northeast from around Amherst Street, Main Street stays close to the crest of the Onondaga Escarpment.
(Note-I refer to the Main Street campus of the University of Buffalo repeatedly throughout this posting because that is where the main part of the Onondaga Escarpment continues eastward. If you are unfamiliar with the area, but still try to follow this scenario on the map, be sure not to confuse this Main Street campus with the larger Amherst campus of the University of Buffalo. I am referring to the campus where Main Street and Bailey Avenue intersect).
At this point, we are atop the escarpment. On nearby Bailey Avenue, there is the steep drop to the north and the gradual drop to the south from the escarpment. On Walden Avenue, east from Sycamore Street, we are going across the gradual southward slope of the Onondaga Escarpment and this can be seen in how it gets higher to the north and lower to the south. The increase in elevation going northward can also be clearly seen on Union Road, north of Walden Avenue.
The Onondaga Escarpment meets Transit Road just south of Sheridan Drive. You can see in the following image, from Google Street View, how the road is cut into the rock. This is the Escarpment. The nearby Eastern Hills Mall might be named for this Escarpment.
I decided that the higher ground in Tonawanda, north of the Highway 290, is not part of this escarpment. This high ground was the result of compacting by bergs of ice sliding down the southward slope of the Niagara Escarpment, to the north, and this was the former shoreline of Lake Tonawanda.
These escarpments are extremely old. There was a tectonic collision between what is now North America and what is now Africa, which formed the system of ridges and mountains known as the Appalachians. Both such tectonic movement and glacial movement is driven by the rotation of the earth. The escarpments were there before this tectonic collision hundreds of millions of years ago, and were affected by it.
Many mountain ranges across the world were formed by tectonic collisions. The thing that makes the Appalachians so unique is that the collision was sliding, rather than a direct collision, and also that the collision front underwent two major changes in direction due to the Canadian Shield to the north, the dense layer of rock underlying the eastern half of Canada.
The first change in direction formed a great curve across Pennsylvania with the focal point at Harrisburg, the state capital. If we look at Georgian Bay, in Ontario, we see that it has a long axis and that if we continue this line to the southeast we come to Harrisburg. This is the line that I named "The Humber Line" and it continues on the opposite side of Harrisburg as the Susquehanna River follows it. The Humber Line represents the change in tectonic pressure are the primary direction of the Appalachian collision shifts from northwestward to northward.
Around the Humber Line, there is a transition zone of the direction of force from the Appalachian collision. This means that the force is uneven in this zone, becoming greater as we move eastward. East of this zone, the tectonic force is greater but more even.
It is within this zone of uneven pressure that we find some special effects on the landscape. The principle is the same as tides. Tides operate not just by gravity, but by a difference in gravity. There are tides in the earth's oceans because the bottom of the ocean is further from the moon and it's gravity than the surface of the ocean, this causes the tidal bulge. The gravity of the sun is much greater than that of the moon, but the sun is about four hundred times as distant as the moon so that there is much less difference in it's gravity between the bottom and surface of the earth's oceans, with the result that the tidal effect of the sun is less than half that of the moon.
BUFFALO'S PARKSIDE LINE (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The Humber Line passes right through Buffalo, the section within Buffalo is what I named "The Parkside Line" because the change in elevation in the rock layers caused by tectonic pressure on the escarpment to the north can be seen as increasing around the Parkside Line as we go eastward.
The name of this line comes from Buffalo's Parkside neighborhood, just east of Delaware Park. The higher level in the rock layers on the Kensington Expressway, Route 33, is obvious as we drive there from the Scajaquada Expressway to the west, Route 198. Here, we are crossing the Humber Line and the higher elevation is due to tectonic pressure from the Appalachians on the escarpment to the north.
At the northern end of Jefferson Avenue, just south of Main Street, we can see that the elevation gets higher if we look eastward along the side streets in the Hamlin Park Neighborhood. This is also a manifestation of the Parkside Line, not the escarpment itself but the increase in elevation due to tectonic pressure on the Onondaga Escarpment to the north from the Appalachian collision.
The Appalachians are a complex system of mountains and ridges that extends across much of the eastern U.S. The southern extent of the Appalachians is around Atlanta. These mountains and ridges formed as a result of a sliding tectonic collision between what is now North America and what is now Africa. The two continents were later cut apart by volcanic activity below, along the line that we call the Mid-Atlantic Ridge. This is the undersea chain of volcanic mountains that extends along the entire floor of the Atlantic Ocean. The ocean floor has been spreading from this line so that the Atlantic is gradually getting wider. There is a place where the Mid-Atlantic Ridge pokes above the water level, forming the island of Iceland. Part of the Appalachians ended up on the other side of the Mid-Atlantic Ridge and now form the Atlas Mountains of Morocco.
The tectonic collision front that formed the Appalachians can be seen on a map to have underwent a great curve in it's direction, so that the northern portion of the Appalachian ridges and mountains are along an east-west line. The focal point of this curve is around the city of Harrisburg, Pennsylvania, which happens to be the state capital of Pennsylvania. This can easily be seen on a map of physical geography.
As described previously, I noticed that Georgian Bay in Ontario had a well-defined long central axis that, if continued to the southeast in a straight line, pointed directly to Harrisburg. Then, I noticed that nearby Lake Erie also had the same type of well-defined long central axis and that the Lake Erie axis both ran parallel to the adjacent section of the Appalachians and also terminated, with a perfect right angle, at the line along the axis of Georgian Bay to Harrisburg.
The next thing that I noticed is that the straight line through the long axis of Georgian Bay to Harrisburg in Pennsylvania passes right through both Toronto and Niagara Falls. Since the line is the boundary region between different zones of geological pressure as a result of the sliding collision that formed the Appalachians, to the west of the line the pressure was primarily northeastward and to the east of the line the pressure was primarily northward, this should show in the local terrain in at least some places.
Sure enough, the Niagara Valley that I described in my blog about Niagara Falls natural history can be explained by the sliding collision that formed the Appalachians and the zones of differing geological pressure. In Toronto, this geological boundary line is easily seen as the change in elevation at the east side of the Humber Valley.
Later, I noticed that this line also passed directly through the city of Buffalo, and I wondered if there was any manifestation of this line to be seen within the Buffalo area. It turned out to be very easy to find, both on land and on the shore of Lake Erie.
First, let me show you something really interesting on the map of Buffalo with regard to the Lake Erie shore. You do not need to be familiar with the area to see this clearly on the satellite imagery. Notice that the far eastern portion of the lake shore forms a straight line and actually runs from north northwest to south southeast. This is the industrial shore of Buffalo, from the southern suburb of Blasdell to downtown Buffalo near the Peace Bridge. Along this section of shore is the Buffalo Harbor, the grain elevators and, the former steel mills for which Buffalo is known.
This straight-line section of Lake Erie shore in Buffalo is actually a part of the Humber Line. This shoreline around downtown Buffalo is included in the line of the Humber Line.
Remember in the section of this posting, "The Detroit-Toledo Line", we saw that the far western shoreline of Lake Erie also forms a straight line that leads to the starting point of the Appalachians. The Detroit-Toledo Line is a line similar to the Humber Line, a boundary between zones of differing geological pressure brought about by the formation of the Appalachians.
So, it is the shift in the thrust direction of the tectonic collision which formed the mountains and ridges of the Appalachians that also formed the downtown Buffalo section of Lake Erie shore. The reason that the Buffalo end of Lake Erie is deeper than the Toledo end now becomes clear, it is where these two lines formed by the Appalachian collision meet at a right angle.
The line of the long axis of Lake Erie can be seen to continue eastward onto land, from the easternmost point of the lake, as the broad V-shaped valley that we see along South Park Avenue, in the southern Buffalo suburb of Lackawanna, with the lowest point of the valley at the intersection with Mile Strip Road.
Next, let's have a look at this line within the city of Buffalo.
There is a highway that crosses Buffalo, known as the Kensington Expressway or Route 33. If we drive westward along this highway from the area of Buffalo Airport or the Interstate 90 highway, there are the layers of rock on either side into which the base for the highway was cut. This limestone was formed eons ago as sea floor that was later forced upward, we can tell this by the fact that the rock is clearly layered. In some places, there are "waves" to be seen in the layers of the rock, indicating that they were forced upward by uneven pressures. These layers of rock are on either side of the highway from the city line with the eastern suburb of Cheektowaga, going into Buffalo.
If we then turn off the Kensington Expressway (Route 33) onto the Scajaquada Expressway (Route 198), and continue westward, we still see the layers of gray limestone along the sides of the highway. But the layers of rock do not continue much further. We can see that there is a definite change in the elevation of the land as we proceed west.
(By the way, this is an area of native Indian names like Scajaquada, Chautauqua, Irondequoit, Tonawanda and, Cheektowaga that are ideal for computer passwords).
Off the expressway, we see that there is a change in the elevation of the land around the Parkside neighborhood, just east of the Buffalo Zoo and Delaware Park. The drop in elevation, going west, continues into the park. On nearby Main Street, if we glance southward from the area of Sisters Hospital and Humboldt Parkway, we see a drop in elevation there also. This drop in elevation in the area can also be seen looking at Fillmore Avenue from Main Street.
It is obvious by the layers of rock, seen along the expressways, that this change in elevation in the Parkside area is not merely the result of glaciation during the ice ages but is based on the underlying layers of rock. Furthermore, I consider the change in elevation to be too broad and smooth to be the work of glacial ice. This is far older than the ice ages, going back hundreds of million of years.
Let's call this section of the Humber Line "The Parkside Line".
Finally, a question that I had not addressed previously. Why is Georgian Bay, in Ontario, such a vast bay at all. It is a roughly oval-shaped body of water that is big enough to be considered as one of the Great Lakes in itself? If the Humber Line, which passes right through the long axis of Georgian Bay, is a boundary of different pressure zones then shouldn't the eastern half of the bay be high ground as we see in Toronto and Buffalo?
The answer is that these two lines formed by the collision which produced the Appalachians, the Humber Line and the Detroit-Toledo Line, meet in the middle of Georgian Bay. This causes the rock layers to be lower in elevation, below water level thus forming a bay, in the same way that the intersection of the long axis of Lake Erie with the Humber Line causes the Buffalo end of Lake Erie to be deeper than the Toledo end.
In the transition zone from the west to the Humber Line, an entire section of the Onondaga Escarpment was broken off and shifted in another direction by the tectonic pressure from the Appalachian collision. I will call this displaced section The Fort Erie Escarpment because it does not have a name, as far as I can tell. This effect is very rare.
This displaced section of the Onondaga Escarpment can be seen on the map as beginning with the peninsula west of Fort Erie that extends into Lake Erie, with Point Albino at it's end. Form there, the escarpment forms a curve past the village of Ridgeville, along North Ridge Road and approaches Ridgemont. The escarpment appears to terminate just west of the Queen Elizabeth Way (QEW).
This is the Onondaga Escarpment around Fort Erie, beginning at the Point Albino Peninsula. This forms the peninsula and is a broken segment of the Onondaga Escarpment that was forced northward by the collision that formed the Appalachians. The second image, from Google Street View, is of the drop in elevation westward along Bowen Road at the end of North Ridge Road.
The Point Albino peninsula can be seen from the U.S. side on the Skyway from downtown Buffalo or along the lake shore of south Buffalo. The end of the peninsula appears higher because it is the tip of the escarpment. The lower adjacent area is formed by the slope of the escarpment. The west shore of the Point Albino peninsula is the ridge, and the east shore is the sloping side of the escarpment.
(One thing that is really helpful in natural history in the area where I live, on both sides of the border, is that ridges are easy to locate because roads often get built along ridges, with the word "ridge" as part of the name of the road. If I see a road on a map with "ridge" as part of the name of the road, then I can be sure that the road is along the line of a ridge).
THE WEST SIDE ESCARPMENT (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The tectonic force of the Appalachian collision, taking place to the south in Pennsylvania, in the transition zone where the direction of the force changed from northwestward to northward, shifted the land so that it broke off a second section of the Onondaga Escarpment and aligned it, much like the Fort Erie Escarpment, as a curve at nearly a right angle to the roughly east-west line of the original escarpment. Shifts like this required millions of years, as well as countless earthquakes.
This second displaced section is what I have named The West Side Escarpment, because it is on the west side of Buffalo, NY. The West Side Escarpment, like the other sections, has a steep side which faces the Niagara River and a gradually sloping side facing toward downtown Buffalo. The sloping side can be seen on the map as many of the streets on the west side are aligned at a different angle to the usual east-west and north-south pattern in the rest of the city.
The presence of the West Side Escarpment can also be seen on the map in the drainage pattern of Buffalo. Even though the terrain gets gradually lower as we go southward, the drainage is to the west instead. To the south, drainage goes through the Buffalo River, and to the north through Scajaquada Creek. These routes for water are to avoid the West Side Escarpment.
It can also be seen on the map how the Scajaquada Expressway, which runs roughly east-west alongside Scajaquada Creek, makes a northward detour to go around Buffalo State College. From the highway, we see that the land on which the college is built is a little bit higher than the ground on the opposite side of the creek and the expressway. This is because the land that the expressway and the creek detour around is the northern end of the West Side Escarpment.
The vertical line is Buffalo's West Side Escarpment, another broken piece of the Onondaga Escarpment. You can see that Scajaquada Creek, and the parallel highway, curves around the northern end of it. Buffalo State University is at the very northern end of the Escarpment. At right the Escarpment continues eastward, to University Heights, as described above, which is just on the other side of the Humber Line.
These broken pieces of the Onondaga Escarpment form a "doorway" through which the Niagara River can flow. We can consider the West Side Escarpment as a door that has opened for the Niagara River.
The section of the thruway that runs parallel to the Niagara River, on the map, is known as route 190 or the Niagara Thruway. While driving on this thruway, we can see that the steep side to the escarpment is higher than the ground on the Canadian shore opposite. In no way is this higher ground a glacial moraine because the bare rock of the escarpment can be seen in places. The higher ground on the U.S. side extends to south of the Peace Bridge, and defines the U.S. side of the Niagara River.
When driving westward on the section of Niagara Street that extends from downtown Buffalo, we find ourselves on terrain that is gradually increasing in elevation until we reach the top at the intersection with Porter Avenue. From here, looking southward toward Lake Erie, we can tell that we are on an escarpment. The high level that we have reached is the flat top of this escarpment, after having just ascended the sloping side. The steep side of the escarpment faces the Niagara River. From Main Street, in Buffalo right downtown, the terrain is lower looking eastward and higher looking westward due to this slope of the West Side Escarpment.
If we go north on the section of Niagara Street which runs parallel to the Niagara River, the flat top and the sloping side of the escarpment can be seen looking eastward along side streets. The escarpment leaves Niagara Street and curves eastward, as we proceed northward. West Delevan Avenue seems to be the northernmost street from which we can see the slope of the West Side Escarpment from Niagara Street.
From Forest Avenue, in the northern west side of Buffalo and just south of Buffalo State College, we see that there is an increase in elevation looking south along the side streets. This is near the northern end of the West Side Escarpment. At the intersection of Grant Street and Forest Avenue, Grant Street is higher to the south and lower to the north than Forest Avenue. There is also a very pronounced drop along West Delevan Avenue from Grant to Niagara Streets.
All of these changes in elevation represent Buffalo's West Side Escarpment. This is a section of the east-west Onondaga Escarpment that was broken off as the terrain shifted beneath it due to the tectonic pressure from the Appalachian collision to the south. There is a one-block low ridge on Rees and Grant Streets, adjacent to Buffalo State College. This is a glacial deposit from when glacial ice from the north, pushing soil and loose rock in front of it, came to a halt when it collided with this escarpment.
The rest of the escarpment, to the east, was pushed northward along with the underlying rock layers and continues around University Heights at the north Main Street campus of the University of Buffalo. On the map, the distance between these two colleges is the gap between the West Side escarpment and the main section of the Onondaga Escarpment to the east which was pushed northward, due to the increasing pressure to the east as the line of pressure from the tectonic collision proceeded eastward.
THE NIAGARA RIVER (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
We know that the route of the Niagara River for water has existed for at least one previous warm period between ice ages, the former St. David's River is the previous manifestation near the Niagara Escarpment. But at the Lake Erie end of the river, we see no evidence at all of such a previous river from before the last ice age.
That is because it flowed along exactly the same route that it does now. The breaking away of two sections of the Onondaga Escarpment by tectonic pressure from the Appalachian collision formed a kind of doorway for the river to flow through, and that is what it does. There is a gap between the Fort Erie and West Side Escarpments, and this is where water and ice bergs found their way through to form the Niagara River. The step side of the West Side Escarpment, seen as higher ground on the U.S. side of the river, acted as a guide to glacial ice and water and this is why the Niagara River is where it is today.
The next question is: why didn't Beaver Creek, the Ontario creek to the west of the Fort Erie Escarpment, become the Niagara River since it was a potential route around all sections of this escarpment? The far eastern shore of Lake Erie, which forms a straight line on a map from downtown Buffalo to the southern suburb of Blasdell, acted as a guide to glacial ice because it was higher ground in the rock layers. This led the ice to the "doorway" between the Fort Erie and West Side Escarpments.
Also the configuration of Lake Erie, which is a fold in the rock strata formed by the Appalachian collision, favored this "doorway" between the two displaced sections of the escarpment because it is closer to the lengthwise axis of Lake Erie, which can be seen to continue inland as the broad V in South Park Avenue with the bottom at Mile Strip Road. If the Niagara River had been carved by moving water alone, and not fragments of ice, it might have been at what is now Beaver Creek.
THE GLACIAL RIDGES OF BUFFALO (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The thing that is difficult about discerning the geological story of Buffalo, involving these escarpments, is that there are also a lot of glacial effects from ice movement at the end of the last ice age about 12,000 years ago. These glacial effects tend to camoflage the escarpments produced by geological changes so that to understand either, it is vital to separate what is geological from what is glacial in origin.
The glacial effects in Buffalo were actually created by the general southward slope of the terrain, combined with these escarpments, so that if we could separate what is of glacial origin then it could help us to better understand the escarpments of geological origin.
When driving westward on the section of Niagara Street that extends from downtown Buffalo, we find ourselves on terrain that is gradually increasing in elevation until we reach the top at the intersection with Porter Avenue. From here, looking southward toward Lake Erie, we can tell that we are on an escarpment. The high level that we have reached is the flat top of this escarpment, after having just ascended the sloping side. The steep side of the escarpment faces the Niagara River. From Main Street, in Buffalo right downtown, the terrain is lower looking eastward and higher looking westward due to this slope of the West Side Escarpment.
If we go north on the section of Niagara Street which runs parallel to the Niagara River, the flat top and the sloping side of the escarpment can be seen looking eastward along side streets. The escarpment leaves Niagara Street and curves eastward, as we proceed northward. West Delevan Avenue seems to be the northernmost street from which we can see the slope of the West Side Escarpment from Niagara Street.
From Forest Avenue, in the northern west side of Buffalo and just south of Buffalo State College, we see that there is an increase in elevation looking south along the side streets. This is near the northern end of the West Side Escarpment. At the intersection of Grant Street and Forest Avenue, Grant Street is higher to the south and lower to the north than Forest Avenue. There is also a very pronounced drop along West Delevan Avenue from Grant to Niagara Streets.
All of these changes in elevation represent Buffalo's West Side Escarpment. This is a section of the east-west Onondaga Escarpment that was broken off as the terrain shifted beneath it due to the tectonic pressure from the Appalachian collision to the south. There is a one-block low ridge on Rees and Grant Streets, adjacent to Buffalo State College. This is a glacial deposit from when glacial ice from the north, pushing soil and loose rock in front of it, came to a halt when it collided with this escarpment.
The rest of the escarpment, to the east, was pushed northward along with the underlying rock layers and continues around University Heights at the north Main Street campus of the University of Buffalo. On the map, the distance between these two colleges is the gap between the West Side escarpment and the main section of the Onondaga Escarpment to the east which was pushed northward, due to the increasing pressure to the east as the line of pressure from the tectonic collision proceeded eastward.
THE NIAGARA RIVER (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
We know that the route of the Niagara River for water has existed for at least one previous warm period between ice ages, the former St. David's River is the previous manifestation near the Niagara Escarpment. But at the Lake Erie end of the river, we see no evidence at all of such a previous river from before the last ice age.
That is because it flowed along exactly the same route that it does now. The breaking away of two sections of the Onondaga Escarpment by tectonic pressure from the Appalachian collision formed a kind of doorway for the river to flow through, and that is what it does. There is a gap between the Fort Erie and West Side Escarpments, and this is where water and ice bergs found their way through to form the Niagara River. The step side of the West Side Escarpment, seen as higher ground on the U.S. side of the river, acted as a guide to glacial ice and water and this is why the Niagara River is where it is today.
The next question is: why didn't Beaver Creek, the Ontario creek to the west of the Fort Erie Escarpment, become the Niagara River since it was a potential route around all sections of this escarpment? The far eastern shore of Lake Erie, which forms a straight line on a map from downtown Buffalo to the southern suburb of Blasdell, acted as a guide to glacial ice because it was higher ground in the rock layers. This led the ice to the "doorway" between the Fort Erie and West Side Escarpments.
Also the configuration of Lake Erie, which is a fold in the rock strata formed by the Appalachian collision, favored this "doorway" between the two displaced sections of the escarpment because it is closer to the lengthwise axis of Lake Erie, which can be seen to continue inland as the broad V in South Park Avenue with the bottom at Mile Strip Road. If the Niagara River had been carved by moving water alone, and not fragments of ice, it might have been at what is now Beaver Creek.
THE GLACIAL RIDGES OF BUFFALO (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The thing that is difficult about discerning the geological story of Buffalo, involving these escarpments, is that there are also a lot of glacial effects from ice movement at the end of the last ice age about 12,000 years ago. These glacial effects tend to camoflage the escarpments produced by geological changes so that to understand either, it is vital to separate what is geological from what is glacial in origin.
The glacial effects in Buffalo were actually created by the general southward slope of the terrain, combined with these escarpments, so that if we could separate what is of glacial origin then it could help us to better understand the escarpments of geological origin.
Between the northern end of the West Side Escarpment and the Parkside Line, the section of the Humber Line through Buffalo of a raised level in the rock strata due to tectonic pressure from the Appalachian collision against the main section of the Onondaga Escarpment to the east, there was a glacial raceway through which a vast amount of glacial ice bergs moved as the glaciers broke up and melted at the end of the last ice age. This raceway can easily be seen on the map as going over what is now Delaware Park and Forest Lawn Cemetery.
This is the Parkside Line, the segment of the Humber Line through Buffalo.
On Main Street, we can easily see that there is a low area in the terrain opposite the cemetery. The rise in elevation from the intersection of Main Street and Jefferson Avenue as we go northward is the Parkside Line. The low elevation of this former glacial raceway can also be seen from Main Street if we look eastward along side streets, such a along Florida Street and Northland Avenue. And also if we look eastward on Eastwood Place and Glendale Place. Across north Buffalo, there is a slow and steady drop in elevation to the south and this funneled a tremendous volume of ice through this raceway. The absence of glacial effects along Main Street north of the Scajaquada Expressway is because all of the loose soil and rock in the area was pushed southward by the ice.
The soil and loose rock that was pushed through this glacial raceway, created by the escarpments, can be seen today. it formed what we could call Buffalo's Medical Ridge because upon it is built many of the buildings in the medical corridor, which includes Buffalo General Hospital and Roswell Park Cancer Hospital. The peak of the Medical Ridge can be see at the intersection of Jefferson Avenue and Best Streets, the glacial ridge continues westward along Best Street from there. The Ridge is also along North and High Streets, and there is a peak at the intersection of Goodrich Street and Main Street. There is somewhat lower high ground from the glacial movement through the raceway at Delaware Park and Forest Lawn Cemetery northward on Jefferson Avenue from the Medical Ridge.
The sloping side of the northern section of the West Side Escarpment also formed a raceway for glacial ice, which plowed up soil and loose rock in front of it. This formed a ridge in the form of a plateau, with a flat top. There is high ground on Delaware Avenue from West Ferry to West Utica Streets, with a long drop from there to the west and a drop that extends beyond Main Street to the east. From this plateau, which we can call The Delaware-Elmwood Ridge for these two well-known streets, the drop from the higher ground going south on Elmwood Avenue begins at Lexington Avenue. The Delaware-Elmwood Ridge extends eastward to Main Street, as higher ground around the intersection of Main Street and East Utica Street, extending southward to Dodge Street.
The central business district in downtown Buffalo is built on another glacial ridge created by the effect of these escarpments on the movement of glacial ice, which pushes soil and loose rock in front of it. This is a low ridge, from being tamped down by ice after being deposited, and fortunately can be seen on the map of the city in how the parallel downtown streets, from south southwest to north northeast which are built upon this Downtown Ridge, we we could call it, differ somewhat from the usual east-west and north-south alignment of the streets. From Church Street, going eastward, there is a gradual slope up to the peak at Main Street. Main and Washington Streets are upon this Downtown Ridge, which is in line with the raceway to the north and also shaped by ice sliding down the slope of the West Side Escarpment. Around Virginia and Edward Streets, it can be seen that Main Street is upon a brad and low ridge. The eastward extent of the ridge can be seen in how the terrain gets lower east of Main Street in the central business district. It also gets lower to the west of Main Street around Dodge Street, Coe Place and, Northampton Street. Tupper Street gets lower to the west, but not to the east, from Washington Street. There is a drop in elevation in both directions along Goodell Street from Washington Street, but more of a drop to the west.
There are various glacial ridges along the gradual southward drop from the main section of the Onondaga Escarpment, such as one along Bailey Avenue with a peak at Doat Street. Harlem Road, north of Walden Avenue, has a number of low ridges formed by glacial deposits. The entire slope of the main section of the escarpment was a slide for glacial ice, and the debris that it pushed in front of it, and the result is the ridge upon which Ridge Road in Lackawanna is built.
Two of the most visible glacial ridges in Buffalo, produced by sliding icebergs at the end of the last ice age, are the Medical Ridge, purple line, and Ridge Road in Lackawanna, red line.
The ice that formed each of these three major glacial ridges affected the shaping of the others, as well. Glacial ice slid down the southward slope of the terrain in general and the eastward slope of the West Side Escarpment into the east side of Buffalo, east of Main Street. Further ice, pushing before it a vast amount of soil and loose rock, pushed up against the ice that had arrived previously so that the soil and loose rock that it pushed was compacted against this first ice. The result is the two nearly perpendicular ridges, the one along the streets of the central business district and the Medical Ridge.
Other glacial ridges in the area are the one on which Lundy's Lane, on the Canadian side, is built and the one on which Center Street in Lewiston is built. These four ridges run east-west because of ice sliding along the southward slope of the escarpments. But the one along Pine Ridge Heritage Blvd, in Cheektowaga, is nearly north-south.
The bergs of ice that had plowed the Medical Ridge forward then had soil and loose rock compacted against it by more ice coming through the raceway, represented by Delaware Park and Forest Lawn Cemetery, a lesser volume of ice by this time, this compacted the ridge along Main Street, north of downtown toward the Scajaquada Expressway. Still more bergs of ice, sliding down the sloping side of the northern portion of the West Side Escarpment, plowed the soil and loose rock that would become the Delaware-Elmwood Ridge and compacted against the now-stationary ice that had plowed forward the Medical Ridge.
CLOSING (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The majority of the mountain ranges of the world were created by tectonic collisions. But most of these collision are direct, while the one that formed the Appalachians was sliding so that it formed extensive systems of ridges, as well as mountains. The only other such collision that I can think of which had more of a sliding than a direct element is the one which formed the Witwatersrand in South Africa.
But what makes the Appalachians so unique is that not only was it a sliding collision, but the collision front underwent major changes in direction due to the Canadian Shield to the north. This is what has created the special effects of these geological lines that I am pointing out as having been as of yet undocumented, and being found nowhere else in the world.
As the direction of the Appalachian collision across Pennsylvania shifted, so that the resulting pressure was northward rather than northwestward, the change in pressure as the line of pressure moved eastward broke off a large section of the Onondaga Escarpment by shifting the terrain beneath it, forming it into a curve with the opening facing east. With more pressure northward, so that it was directly against the east-west escarpment but less difference in pressure from one point along the escarpment to another, the process repeated with a smaller section of the escarpment being broken off and forming a curve. These are seen today as the Fort Erie and the West Side Escarpments that I have described here.
In the zone of pressure direction transition around the Humber Line, the pressure line from the tectonic collision had first been brought against the escarpment in the west, and increased as the pressure line from the front of the collision proceeded eastward. To the east of this transition zone, pressure northward had reached it's maximum but was also more even so that the main part of the Onondaga Escarpment was shifted northward, from the University of Buffalo Main Street campus eastward, but there was no more fragmentation of the escarpment due to the evenness of the pressure.
We can see how the entire landscape was shifted northward by the pressure from the collision by the location of Point Albino, at the end of the Point Albino peninsula to the west of Fort Erie. The fact that this southernmost section of the Fort Erie Escarpment lies about 2 km south of the southernmost extent of the West Side Escarpment is a vivid illustration of how the entire landscape shifted northward as the northward pressure increased and the line of pressure moved eastward.
This means that the entire terrain had been pushed northward by 2 km by the time the West Side Escarpment was broken away from the main section of the Onondaga Escarpment. The rest of the escarpment was pushed still further to the north, leaving the West Side Escarpment behind, to where we see it today continuing at the Main Street Campus of the University of Buffalo. This means that this escarpment, and it's continuation eastward, was once to the south in a line with Point Albino. Notice that the northern end of the West Side Escarpment, represented on the map by Buffalo State College around which Scajaquada Creek and the parallel Scajaquada Expressway curves to the north, lies on a straight line from Point Albino to the University of Buffalo where the main section of the escarpment continues eastward.
The main section of the escarpment east of here did not undergo any more breaks while being shifted northward to it's present position because the pressure from the south was more even. But even so, there was still some change in pressure moving eastward and this can be seen in how the escarpment curves from the University of Buffalo to the intersection of Main Street and Harlem Road in Williamsville to the intersection of Sheridan Drive and Transit Road. This is also how the Niagara Escarpment, to the north, can be seen to curve on the map (it shows as a dark green line of the trees on it south of, and parallel to, the shore of Lake Ontario) east of the "breaking point" of that escarpment just southwest of St. Catharines. The Niagara Escarpment "broke" at this point, but only at one point and not into pieces like the Onondaga Escarpment.
The bergs of ice that had plowed the Medical Ridge forward then had soil and loose rock compacted against it by more ice coming through the raceway, represented by Delaware Park and Forest Lawn Cemetery, a lesser volume of ice by this time, this compacted the ridge along Main Street, north of downtown toward the Scajaquada Expressway. Still more bergs of ice, sliding down the sloping side of the northern portion of the West Side Escarpment, plowed the soil and loose rock that would become the Delaware-Elmwood Ridge and compacted against the now-stationary ice that had plowed forward the Medical Ridge.
CLOSING (A SECTION OF "THE VERY SPECIAL ESCARPMENTS OF BUFFALO AND FORT ERIE")
The majority of the mountain ranges of the world were created by tectonic collisions. But most of these collision are direct, while the one that formed the Appalachians was sliding so that it formed extensive systems of ridges, as well as mountains. The only other such collision that I can think of which had more of a sliding than a direct element is the one which formed the Witwatersrand in South Africa.
But what makes the Appalachians so unique is that not only was it a sliding collision, but the collision front underwent major changes in direction due to the Canadian Shield to the north. This is what has created the special effects of these geological lines that I am pointing out as having been as of yet undocumented, and being found nowhere else in the world.
As the direction of the Appalachian collision across Pennsylvania shifted, so that the resulting pressure was northward rather than northwestward, the change in pressure as the line of pressure moved eastward broke off a large section of the Onondaga Escarpment by shifting the terrain beneath it, forming it into a curve with the opening facing east. With more pressure northward, so that it was directly against the east-west escarpment but less difference in pressure from one point along the escarpment to another, the process repeated with a smaller section of the escarpment being broken off and forming a curve. These are seen today as the Fort Erie and the West Side Escarpments that I have described here.
In the zone of pressure direction transition around the Humber Line, the pressure line from the tectonic collision had first been brought against the escarpment in the west, and increased as the pressure line from the front of the collision proceeded eastward. To the east of this transition zone, pressure northward had reached it's maximum but was also more even so that the main part of the Onondaga Escarpment was shifted northward, from the University of Buffalo Main Street campus eastward, but there was no more fragmentation of the escarpment due to the evenness of the pressure.
We can see how the entire landscape was shifted northward by the pressure from the collision by the location of Point Albino, at the end of the Point Albino peninsula to the west of Fort Erie. The fact that this southernmost section of the Fort Erie Escarpment lies about 2 km south of the southernmost extent of the West Side Escarpment is a vivid illustration of how the entire landscape shifted northward as the northward pressure increased and the line of pressure moved eastward.
This means that the entire terrain had been pushed northward by 2 km by the time the West Side Escarpment was broken away from the main section of the Onondaga Escarpment. The rest of the escarpment was pushed still further to the north, leaving the West Side Escarpment behind, to where we see it today continuing at the Main Street Campus of the University of Buffalo. This means that this escarpment, and it's continuation eastward, was once to the south in a line with Point Albino. Notice that the northern end of the West Side Escarpment, represented on the map by Buffalo State College around which Scajaquada Creek and the parallel Scajaquada Expressway curves to the north, lies on a straight line from Point Albino to the University of Buffalo where the main section of the escarpment continues eastward.
The main section of the escarpment east of here did not undergo any more breaks while being shifted northward to it's present position because the pressure from the south was more even. But even so, there was still some change in pressure moving eastward and this can be seen in how the escarpment curves from the University of Buffalo to the intersection of Main Street and Harlem Road in Williamsville to the intersection of Sheridan Drive and Transit Road. This is also how the Niagara Escarpment, to the north, can be seen to curve on the map (it shows as a dark green line of the trees on it south of, and parallel to, the shore of Lake Ontario) east of the "breaking point" of that escarpment just southwest of St. Catharines. The Niagara Escarpment "broke" at this point, but only at one point and not into pieces like the Onondaga Escarpment.
