Geologic units in Gray county, Kansas

Loess (Holocene to Pleistocene) at surface, covers 71 % of this area

eolian silts

Dune Sand (Holocene to Pleistocene) at surface, covers 22 % of this area

unconsolidated dune sand

Alluvium (Holocene to Pleistocene) at surface, covers 4 % of this area

unconsolidated sand, silt, clay, and gravel

Alluvium (Pleistocene) at surface, covers 4 % of this area

unconsolidated sand, silt, clay, and gravel

Greenhorn Limestone and Graneros Shale (Late Cretaceous) at surface, covers < 0.1 % of this area

Greenhorn FM- thin bedded gray, chalky limestone and calcareous shale. Graneros Shale- fissile, noncalcareous, gray shale locally contains sandstone and siltstone beds.