An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the
United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Google Analytics Dashboard for Possible further evidence for 3.8 b.y.-old rocks in the Minnesota River Valley of southwestern Minnesota
Possible further evidence for 3.8 b.y.-old rocks in the Minnesota River Valley of southwestern Minnesota