Indiana Geological and Water Survey "golden spike" drill core.

By National Cooperative Geologic Mapping Program 2021 (approx.)

This image of a drill core shows four sections of core in casings with sediment ranging in size from gravel to silt.

Detailed Description

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. The information gained from these cores is used to constrain 3D models of the subsurface geology and glacial deposits in the Great Lakes region.

Sources/Usage

Public Domain.

Image courtesy of the Indiana Geological and Water Survey.