Inside an Esker, Lawrence County
There are no active gravel pits in the Jacksville Esker to visit to see the internal structure of an esker. This photo is from a sand and gravel pit that was developed in another esker along US 19 between Moraine and McConnells Mill State Parks.
The layers of sand and gravel inside an esker are usually arranged in a dome-shape across the esker, as seen in this photo.
In addition, the beds of sand and gravel are offset along faults downward toward the margin of the esker because of slumping resulting from the melting of the supporting ice walls of the tunnel. The sand layers labeled "a" in this photo are all the same sand layer that has been offset along the faults marked on the photo.
Photo by Gary Fleeger, PaGS