Saturday, July 11, 2009

Burnt Ship Creek And The American Falls

Burnt Ship Creek is the wide marshy area that separates Grand Island from Buckhorn Island at the northwest corner of Grand Island, a short distance from the North Grand Island Bridges. I realize that Burnt Ship Creek could only have been formed by sliding icebergs as the glaciers melted and broke up at the end of the last ice age.

Image from Google Earth

The geometry of Burnt Ship Creek is completely wrong for it to have been carved by the river. The thing that is striking about Burnt Ship Creek is how symmetrical it's width is, at least until it widens in it's far western section. Another thing is it's abrupt right angle turn.

How can we see a marsh with near-symmetrical width and which makes an abrupt 90 degree turn and not think that something very unusual was at work here?

But suppose Burnt Ship Creek was carved by one or more sliding icebergs that broke free from the melting glacier and slid southward across the LaSalle section of Niagara Falls, NY. That would explain the existence of the creek perfectly. This explanation fits with what we see of the slope of the land caused by the underlying rock strata. The slope is to the south and west.

From Niagara Falls Blvd., it is fairly easy to see the downward slope of the ground going southward around 75th to 77th Sts. in Niagara Falls. Then, the upper rapids in the Niagara River just west of Grand Island is caused by the downward slope of the underlying rock strata going westward. 

The sliding icebergs, wearing away the ground beneath them as they moved, slid across what is now the Niagara River and then abruptly switched direction when the primarly slope of the underlying ground went from southward to westward. This explains the 90 degree angle of the marsh.

We can see the underlying slope of the ground at Burnt Ship Creek by the fact that it's western, downstream, end is much more watery than it's beginning. We can also see that the northern shore of nearby Navy Island forms almost a straight line with the southern shore of Burnt Ship Creek. This is because it was worn away by the iceberg as it continued westward. I can think of no better explanation of why this creek exists.

WHY ARE THERE TWO FALLS AT NIAGARA?

An enduring mystery of Niagara Falls is why does all the water not go over one falls. There is a definite tilt of the underlying rock strata in the area to the southwest. This is why water goes over the main falls at Niagara, the Horseshoe Falls. So why does about 8% of the water that is set to go over the falls make a northward detour, seemingly against gravity, to form a second falls at Niagara, the American Falls. Actually two other falls are formed by this detour, the other is the smaller Bridal Veil Falls.

A glacier brings a virtual ocean of water to areas high on land where this volume of water would not otherwise be and when the glacier melts, this water has a permanent effect on the land. In addition, if there is a slope to the land when a glacier melts, massive chunks of ice will break off and slide along the slope. This happened extensively at Niagara Falls.

There is a westward and southward slope to the underlying rock strata in the area of Niagara Falls, USA and so secondary glaciation in the form of sliding icebergs at the end of the ice age was a factor in forming the falls as we see them today. The upper river from North Tonawanda down to the falls is the lakebed of the former Lake Tonawanda that existed for most of the time since the end of the last ice age about 12,000 years ago.

The reason that this was the lakebed is that it is at the low line of a southward slope to the land in the area and itself has a westward slope toward the falls. We can tell by the Niagara Falls Moraine, the high ground on the Canadian side around the falls that it was impacted by massive blocks of ice sliding across the westward slope, seen in the Upper Rapids just before the falls.

The southward slope, best seen from Niagara Falls Blvd. looking southward along the numbered streets in the 70s in the LaSalle section of Niagara Falls is what deposited these icebergs from the melting glacier in the line that became the upper river after Lake Tonawanda drained.

Now, let's go back to Burnt Ship Creek. (Note-I am unsure where the name "Burnt Ship Creek" comes from. Presumably, in the days of wooden warships in the area, one ship fired hot shot into another).

I established that Burnt Ship Creek was formed by a massive iceberg that had slid down the southward slope in the 70s streets in LaSalle and then began sliding westward, toward what is now the falls, when it reached a point in which the slope was more westward than southward. This scraped away the ground along it's path and the result was Burnt Ship Creek, a wide marsh with a 90 degree angle, after Lake Tonawanda drained.

If the iceberg that formed Burnt Ship Creek had continued on it's course, it veers somewhat northward on it's westward course after it leaves the western end of Burnt Ship Creek, it will move along the course of the channel between Goat Island and the mainland that leads to the American Falls.

In some areas the general southwest slope of the underlying rock strata is more southward and in others, it is more westward. The route taken by this iceberg from Burnt Ship Creek to what is now the falls avoids the southward sloping areas so that the falls it caused to form results from a detour away from the main falls which seemingly defies gravity. The river was not there at the time, of course, so the iceberg continued westward to collide with the high ground on the Canadian side, where it finished melting.

The channel north of Goat Island leading to the American Falls has something in common with Burnt Ship Creek. Both get wider near their downstream, western ends. This can be explained by the fact that the iceberg that formed both was actually a mass of ice that was fragmenting and melting as it went along, eroding away the ground as it went, and thus spreading out. This formed a channel through which water later flowed from the main stretch of river and thus is why we have two falls, actually three, instead of just one.

Image from Google Earth

The sliding iceberg that formed Burnt Ship Creek continued westward to carve the channel through which water flows to the American Falls.

In a similar way, we could say that Goat Island (the land separating the two main falls) exists because the southward slope in the upper rapids, which is why the water above the falls is deeper on the Canadian side, kept such large chunks of ice moving westward away from it.

If we draw a straight line from the center of the wide marshy area through which Burnt Ship Creek flows at the point where it makes a 90 degree bend and continue the line, which represents the route of the sliding iceberg that formed both Burnt Ship Creek and the American Falls, as shown below:

Image from Google Earth

The line passes exactly along the center of the western part of the wide marshy area around Burnt Ship Creek, seen in close-up below. The highway crossing the creek is the I-190.


This shows that both Burnt Ship Creek and the American Falls were formed by a sliding iceberg, at the end of the last ice age, as described here. The small islands just above the American Falls are formed of the ground that was left intact as the iceberg broke up.

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