Geologic map of the United States' surface

"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."

The United States Geological Survey provides an Earth's Surface geology layer that maps geologic units exposed at the surface across the conterminous United States, spanning Quaternary glacial deposits and alluvium to Precambrian crystalline bedrock. Western and southeastern coverage is a composite of 29 state geologic maps. The glaciated Midwest and Northeast combine 21 state maps of pre-Quaternary bedrock, 8 state maps of Quaternary deposits, and 18 USGS Quaternary Atlas Series maps used where state maps were not available. Data and additional map layers are available for download from USGS, and deeper-time datasets extend back billions of years.

Read at FlowingData