Images

Depiction of a national geologic map of the U.S. used as an illustration for EDMAP and STATEMAP outreach

This is a 20 foot section of a drill core collected by the Indiana Geological and Water Survey (IGWS). IGWS geologists dub these cores "golden spikes" when they are drilled deep enough to reach the underlying bedrock.

This map details the subsurface contact between the consolidated Paleozoic bedrock surface and the overlying unconsolidated Quaternary-aged sediments. This image is used with the permission of the Ohio Department of Natural Resources, Division of Geological Survey and the Indiana Geological and Water Survey. 

Glacial deposits are sampled deep underground by drilling (Lake County, Illinois). Geologists analyze sediments to determine physical characteristics, such as the capacity to hold and transmit water or ability to accept a load from a building or bridge.

Illinois State Geological Survey (ISGS) geologists and the State of Illinois are featured in the History Channel's internationally popular program, How the Earth Was Made: America's Ice Age.

Geophysical surveys at the land surface help scientists explore the subsurface geology. Here geologists collect geophysical data using geophones. In the resulting geophysical profile, colors highlight key horizons.

3D geologic framework model from west-central New Mexico; graphic shows stratigraphic units in the model being sequentially removed to reveal the deeper units. Faults used in the model appear as vertical “ribbons” as geologic layers are removed.

This map shows the depth to bedrock for Cass County, Minnesota which represents the thickness of unconsolidated sediment above bedrock. It is part of the County Geologic Atlas project being conducted by the Minnesota Geological Survey. Maps like these help provide information about the glacial deposits that overlie the bedrock. 

This diagram depicts the Quaternary Stratigraphy of Cass County, Minnesota shown in six different cross sections located throughout Cass County, MN as indicated in the bottom right indicator map. These cross sections are representative of the materials to be encountered between the land surface and bedrock. 

OLYMPUS DIGITAL CAMERA

During invasions of the ice sheets (about 10,000 to 1,800,000 years ago), the glacial landscape of the Central Great Lakes region was a foreboding and barren place. In this scene, melting along the front edge of the continental ice sheet feeds water and sediment into a river and glacial lake.

Cover page for the USGS Open File Report 99-349. Read the original report here: https://www.usgs.gov/publications/mapping-glacial-geology-central-great…

Each advance and retreat of the ice sheet left behind a landscape composed of patches of clay, silt, sand, gravel and till, commonly capped by soil. This block diagram provides an artistic depiction of a modern landscape on glacial deposits. 

This is the cover page of USGS Circular 1190. View the publication here: https://pubs.usgs.gov/circ/c1190/

King and Beikman's 1974 Geologic Map of the United States (1974 Geologic Map of the United States)