The Fort Riley Limestone is a Kansas

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Pale ...

stratigraphic unit of member rank and historic building stone, sold commercially as fine-grained Silverdale, having at one time been quarried at

Silverdale, Kansas Silverdale is an unincorporated community in Silverdale Township, Cowley County, Kansas, United States. As of the 2020 census, the population of the community and nearby areas was 61. History The post office was established June 5, 1871, and ...

. This limestone outcrops in east-central

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to ...

, extending into northeast-central Oklahoma and southeastern

Nebraska Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the so ...

, in the

Midwestern United States The Midwestern United States, also referred to as the Midwest or the American Midwest, is one of four census regions of the United States Census Bureau (also known as "Region 2"). It occupies the northern central part of the United States. I ...

. Its conspicuous "rim rock"

marker horizon Marker horizons (also referred to as chronohorizons, key beds or marker beds) are stratigraphic units of the same age and of such distinctive composition and appearance, that, despite their presence in separate geographic locations, there is no d ...

outcrop caps the bluffs overlooking the original buildings of

Fort Riley Fort Riley is a United States Army installation located in North Central Kansas, on the Kansas River, also known as the Kaw, between Junction City and Manhattan. The Fort Riley Military Reservation covers 101,733 acres (41,170 ha) in G ...

, as well as the

Marshall Army Airfield Marshall Army Airfield (MAAF) is a military airfield located on Fort Riley, Kansas, United States. It was opened in 1921. The primary mission of MAAF is to provide fully integrated fixed base helicopter operations for the Combat Aviation Briga ...

opposite the

Kansas River The Kansas River, also known as the Kaw, is a river in northeastern Kansas in the United States. It is the southwesternmost part of the Missouri River drainage, which is in turn the northwesternmost portion of the extensive Mississippi River dr ...

. ap legendbr/>''Note the

below the blue-line Pb marker bed.''

References

Permian Kansas Permian geology of Nebraska Stratigraphy of Oklahoma Limestone Building stone Geological members {{Kansas-geologic-formation-stub

See also

References