ISGS - Maps and a 3-D Model of the Maquoketa Formation
Surface and Thickness Maps and a Three-dimensional Model of the Maquoketa Formation in Lake County, Illinois
The Maquoketa is composed of impermeable to low permeability shales and dolomites that form an important aquitard between the locally recharged Silurian aquifer and the deeper bedrock aquifers.
Left is a three-dimensional representation of the thickness of the Maquoketa Formation.
Updated 10/27/2009 SLD