well this is an interesting topic! never heard of it. google earth here i come. what's the glacial/geologic structure allowing it to be 200 feet deep in north dakota?
it just looks like your run of the mill but much deeper than normal kettle lake. @
Allen ?
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google earth takes me to little lake south of a farm. i was looking at that one. google maps takes me to a decent sized lake by a wildlife refuge. i assume that's the one you guys are talking about?
I am not at all familiar with Lake George's specific construction. That article said it was from "thrusting of ice" during the last glaciation, which suggests it is essentially a divot on the Earth's surface. Oddly enough, if I remember correctly, that's how Devils Lake was formed. Sully's Hill on the south side is the dirt pushed out of the DL basin.
Most of the Prairie Potholes (lakes and big wetlands) in ND are the result of large chunks of ice that remained in place as the rest of the glacier melted around them. Glaciers actually carry a lot of dirt, rocks, sand, gravel, you name it. So when the ice melts it carries that material away as sediment (aka glacial outwash) and deposits it alongside those HUGE chunks of ice. Eventually though, that ice shall also melt, but where it sat on the Earth's surface is now surrounded by higher ground and you have this large void that remains filled with water.
Anyway, I'd have to look closer at Lake George to see if it really is a divot (is there a large pile of dirt, most likely on its south or southwest side) or if it's just the deepest lake I know of formed by the same processes that created the vast majority of our other Prairie Potholes.
It's salinity would suggest it intersects the Dakota Sandstone (the Dakota daylights out in the RRV, think of Kelly's slough by Grand Forks and that whole strip of saline wetlands that runs N-S in the RRV), but I would have guessed that formation to be somewhat deeper in Kidder county. So I am not 100% sure on that one.