extinct glacial lake
- Extinct Glacial Lake
Simply put, a glacier-created lake that drained, sometimes catastrophically, when a glacier or part of a glacier (like one "lobe" of the glacier) melted back, or simply broke. You can see this at Glacial Lake Wisconsin, the lake bed of which remains visible in Adams and Juneau Counties of that state. Much of the Fox Valley there was once under Glacial Lake Oshkosh as well.
Aren't all glacial lakes extinct? Either find a glacier and check, or look for a really big flat spot where they say a glacier used to be, and if the glacier still hasn't come back by the time you get there, then maybe you've got your extinct glacial lake.