Last week we visited the peninsula that lies between North and South Lakes at the North/South Lake Campground. That campground lies in one of the most scenic vicinities in all of the Catskills and it has been a favorite site for tourists for many generations. But we are not tourists; we are geologists, and we are not there just to look at the scenery. We are asking the simple geologic question “how did that peninsula form?” This is a typical, even commonplace sort of question for a geologist to ask. We, starting today, are going to use the scientific method in our effort to solve this problem. Step one in the scientific method is to identify a problem. Step two is simply to learn as much as possible about the puzzle. And we started to do both of these two things last week. But now it’s time to move on. Step three is to conjure up what are called multiple working hypotheses. Those are two or more possible solutions to the problem. They emerge, one by one, as we scientists study a problem and then go on to think about it.
One of the most important ways to study this problem was to identify how the glaciers moved in this area back during the ice Age. We dealt with that in some earlier columns. Those were the five we published between Aug 18th and Sept. 15th of last year. You clip these and save them, right? Back then we documented flows of the glaciers from those scratches, AKA the glacial striations, that they produced. As the glaciers circled around the campground, they left those striations and these all have compass directions. We found and recorded as many of them as possible. From those we could put together the map you see here. The arrows represent the many glacial striations that we found.
That map shows ice advancing across South Lake as it approached that peninsula from the southwest. Another glacier crossed North Lake as it advanced from the east. The two glaciers seem to have collided with each other right where that peninsula is seen. Both the peninsula and the collision zone are represented by that jagged zigzag line. This hypothesis seems to solve our problem. The peninsula, as we thought last week, is the product of advancing glaciers. It is a mass of earth bulldozed to where we see them by the advancing ice. That explains all those boulders that we saw, along with the heaps of earth. It is what geologists call a glacial moraine. That makes it a curious type of moraine. There was not just one glacier but two of them. So, we have come up with the term “collision moraine” to describe it. It’s a nice explanation and a very appealing one. But that can be a problem in science. If you do come up with such an attractive hypothesis, then you may hesitate to explore the problem further. Maybe there is a better explanation out there, but you are not going to find it.
So, this is not the end of the story. If possible, we scientists always try to come up with more than one hypothesis. We do have one other. Let’s do that next week.
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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