Geologic units in Gove county, Kansas

Niobrara Chalk (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 15 % of this area: interbedded, soft, light-gray calcareous shale and chalk
Lithology: shale; limestone
Loess (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 73 % of this area: eolian silts
Lithology: silt
Alluvium (Phanerozoic | Cenozoic | Quaternary | Pleistocene Holocene) at surface, covers 5 % of this area: unconsolidated sand, silt, clay, and gravel
Lithology: gravel; sand; silt; clay or mud
Ogallala Formation (Phanerozoic | Cenozoic | Tertiary | Miocene) at surface, covers 5 % of this area: massive to cross-bedded, generally arkosic sand, silt and gravel, locally cemented with calcium carbonate; also contains limestone, volcanic ash, diatomaceous marl, opaline sandstone and bentonitic clay
Lithology: arkose; limestone; volcanic ash; carbonate; sandstone; claystone
Pierre Shale (Phanerozoic | Mesozoic | Cretaceous-Late) at surface, covers 0.3 % of this area: thin bedded gray to brownish gray shale; contains concretions, selenite crystals, thin beds of bentonite and locally chalky beds.
Lithology: shale