Even if you never use that knowledge professionally, or practice it to earn your living, it gives you an insight into that field of knowledge, a survey of its past accomplishments and failures, as well as how it fits into the library of all man’s knowledge. It doesn’t matter what the field is, or whether or not you ever are exposed to it again, it gives you an idea of how complex and rich all other fields of knowledge are, even if you should never have any experience of it at all. That understanding in itself is of great value.

I never took any courses in pharmacy, or Slavic languages, or microbiology, or the history of the Persian empire; but I know that there are people out there who know as much about those fields as I do about mine, and some who know a lot more. I have an understanding of just how rich and beautiful and detailed is the whole landscape of human knowledge, and how little any one of us sees of it. I have a good idea of just how much it is I DON’T know, and that is a humbling, but extremely valuable experience.

I spent a lot of time in Morraine State Park in Pennsylvania, and I could never actually see the traces the ice left on the landscape until they were pointed out in the park brochure. That is a wonderful thing to have, even if you never use it professionally. You have a familiarity, an understanding, of the Earth at a visceral level right at your fingertips. I envy that.

We call them “proglacial lakes.” There are a couple of different kinds of proglacial lakes, in this case, they might also be called glacial moat lakes.

When a big ice sheet melts, isostatic rebound of the crust is delayed, resulting in a moat around the retreating ice. Drainage is poorly defined, constantly changing, or may not exist at all. In this case, some of these lakes were part of a much larger lake known as Lake Agassiz, named after the famous founding glaciologist.

As for the seemingly regular spacing, I’m not sure why that might be. The first step would be to apply some geographic statistics to the bodies of water and see if there is a true periodicity verses they just look regularly spaced.

I remember when I was taking a glaciology class in grad school under a rather well published glaciologist, when we were discussing the retreat of the Laurentian Ice Sheet, I noted that the Great Lakes were located at the contact between the Precambrian rocks of the Canadian Shield and the much younger sedimentary layers. He responded with a raised eyebrow, a “hmmm”, then a suggestion that that would make an interesting study. If you look at a geologic map of Canada, this same relationship holds for the other big water bodies. So I believe there is something about this contact between hard and soft rocks localizing the proglacial lakes, possibly due to the original scouring at the base of the ice sheet coupled with isostatic depression.