Geologic units in Jewell county, Kansas

Loess (Holocene to Pleistocene) at surface, covers 54 % of this area

eolian silts

Niobrara Chalk (Late Cretaceous) at surface, covers 19 % of this area

Interbedded, soft, light-gray calcareous shale and chalk

Alluvium (Holocene to Pleistocene) at surface, covers 13 % of this area

unconsolidated sand, silt, clay, and gravel

Carlile Shale (Late Cretaceous) at surface, covers 10 % of this area

Chalky shale with bentonite and thick chalk beds, dark gray fissile shale containing septarian concretions, and fine-grained sandstone.

Greenhorn Limestone and Graneros Shale (Late Cretaceous) at surface, covers 4 % 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.

Niobrara Formation (Late Cretaceous) at surface, covers 0.1 % of this area

Argillaceous chalk, limestone and shale. Chalk is medium gray to white, interbedded with thin layers of chalky shale; contains many fossil clams, oysters, and formanifera. Limestone is light gray to medium gray and yellowish gray, interbedded with medium-gray chalky shale; also contains fossil clams, oysters, and formanifera. Bedding plans commonly marked by thin layers of gypsum and locally a thin bed of red flint occurs at top of unit. Approx. max thickness 570 ft.

Carlile Shale (Late Cretaceous) at surface, covers < 0.1 % of this area

Shale, limestone, and sandstone. At top, locally 5 feet of gray to pale-yellowish brown siltstone or very fine grained sandstone. Upper 200 feet of shale is drak gray to medium gray; locally contains ironstone concretions, and interbedded with thin siltstone. Lower 80 feet of shale is medium gray, calcareous, and contains many very thin bedded, fossiliferous, shaly limestone and calcareous shale layers. Approx. max thickness 300 ft.

Ogallala Group or Formation (Miocene) at surface, covers < 0.1 % of this area

Silt, sand, sandstone, gravel and conglomerate. Predominantly interfingered fine- to coarse grained, poorly sorted, arkosic, fluvial deposits of light-gray, light-olive-gray, and grayish-green calcareous silt and sand, and locally poorly consolidated conglomerate, sandstone, and siltstone.