Is there any sort of database that provides the locations of exposures of certain geologic groups or formations?
I ask because I have read that halite occurs in the Michigan Basin, and specifically occurs in beds of the Salina Formation (Silurian) and the Detroit River Group (Devonian). I would love to find a source (preferably a map) that provides locations where these features (or really, halite) are at or near the surface.
Thanks.