Ogallala Formation

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
State Kansas
Name Ogallala Formation
Geologic age Miocene
Lithologic constituents
Major
Sedimentary > Clastic > Sandstone > Arkose (Bed)
Minor
Igneous > Volcanic > Alkalic-volcanic (Pyroclastic-air fall)
Sedimentary > Clastic > Mudstone > Claystone (Bed)
Sedimentary > Carbonate > Marlstone (Bed)
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Sandstone (Bed)
Comments approximate thickness 0-350 ft. in outcrop. May be partly upper Miocene in age
Stratigraphic units locally includes Rexroad, Laverne and Delmore FM's.
References

Ross, Jorgina A., 1991, Geologic Map of Kansas: Kansas Geological Survey, Univ. of Kansas, Map M-23, scale 1:500,000.

Zeller, D.E., ed., 1968, The Stratigraphic Succession in Kansas, State Geological Survey of Kansas Bull. 189.

NGMDB product
Counties Cheyenne - Clark - Decatur - Edwards - Ellis - Ellsworth - Finney - Ford - Gove - Graham - Greeley - Hamilton - Hodgeman - Kearny - Kingman - Lane - Logan - McPherson - Marion - Meade - Morton - Ness - Norton - Osborne - Pawnee - Phillips - Rawlins - Reno - Rooks - Rush - Scott - Seward - Sheridan - Sherman - Smith - Stanton - Thomas - Trego - Wallace - Wichita