GROUND WATER ATLAS of the UNITED STATES
Iowa, Michigan, Minnesota, Wisconsin
HA 730-J
Silurian-Devonian aquifer
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Hydrogeology
Figure 74 Correlation chart describing characteristics of the
Silurian-Devonian aquifer in Iowa (143K)
downloadable tiff file J074.tif.gz (1MB
compressed)
Figure 75 Correlation chart describing characteristics
of the Silurian-Devonian aquifer in Wisconsin (136K)
downloadable tiff file J075.tif.gz (1.1MB
compressed)
Figure 76 Correlation chart describing characteristics
of the Silurian-Devonian aquifer in Michigan (166K)
downloadable tiff file J076.tif.gz (1.4MB
compressed)
Figure 77 Map showing areas of the Silurian-Devonian
aquifer that are unconfined and those areas that are overlain
by younger rocks (335K)
downloadable tiff file J077.tif.gz (3MB
compressed)
Figure 78 Map showing location of karst features
in the Silurian-Devonian aquifer in Iowa (290K)
downloadable tiff file J078.tif.gz (2.7MB
compressed)
Figure 79 Map showing location of karst features
in the Silurian-Devonian aquifer in Michigan (248K)
downloadable tiff file J079.tif.gz (2.2MB
compressed)
Figure 80 Generalized block diagram showing the
aquifer systems in Iowa (437K)
downloadable tiff file J080.tif.gz (3.5MB
compressed)
Figure 81 Map showing the altitude of the base
of the Silurian-Devonian aquifer contour in Iowa and Wisconsin
(285K)
downloadable tiff file J081.tif.gz (2.4MB
compressed)
Figure 82 Map showing potentiomentric surface of
the Silurian-Devonian aquifer in Iowa and Wisconsin (236K)
downloadable tiff file J082.tif.gz
(2.9MB compressed)
downloadable tiff file J074.tif.gz (1MB
compressed) 
downloadable tiff file J075.tif.gz (1.1MB
compressed) 
downloadable tiff file J076.tif.gz (1.4MB
compressed) 
downloadable tiff file J077.tif.gz (3MB
compressed) 
downloadable tiff file J078.tif.gz (2.7MB
compressed) 
downloadable tiff file J079.tif.gz (2.2MB
compressed) 
downloadable tiff file J080.tif.gz (3.5MB
compressed) 
downloadable tiff file J081.tif.gz (2.4MB
compressed) 
downloadable tiff file J082.tif.gz
(2.9MB compressed)