Geologic map of the United States’ surface

The United States Geological Survey published composite maps and data for the country’s geological makeup.

The Earth’s Surface geology layer depicts geologic units exposed at the Earth’s surface in the conterminous United States, ranging in age from Quaternary glacial deposits and alluvium to Precambrian crystalline bedrock. In the U.S. West and Southeast, the map is a composite of 29 state geologic maps depicting geology at the Earth’s surface. In the glaciated region of the Midwest and Northeast, the map is a composite of 21 state geologic maps depicting pre-Quaternary rocks (“bedrock”), 8 state geologic maps depicting Quaternary deposits, and 18 USGS Quaternary Atlas Series maps depicting Quaternary deposits. The Quaternary Atlas maps were used where modern state geologic maps were not available.

You can download the data and other map layers through USGS. As per the title, the above only shows the surface. They have data that stretches back billions of years ago.

[via Beautiful Public Data]