Why are these here? Traditional Cache
-
Difficulty:
-
-
Terrain:
-
Size: 
(small)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Maybe a micro maybe a small. It's one of those in-betweeners.
As we were caching through the western edge of Lake Elmo Park Reserve, Q asked a simple question. Sure, we could have checked Wikipedia, or called our favorite geologist, but it seemed better to pose the question to the broader geocaching community.
So to all you would be scientists and weekend Earth Cachers: Why are these here?
Additional Hints
(No hints available.)