Red Hills Physiographic Region


Gayla R. Corley
Dr. James S. Aber, Instructor

Table of Contents
Introduction Description of Study Region
Methodology Literature Review
Geology of Red Hills Conclusions
Photo Gallery References

Overview of Red Hills, Barber County, with gypsum exposure, white in upper center of photograph.
Kite aerial photograph by Susan Aber.


Kansas presently has eleven physiographic regions designated by the Kansas Geological Survey. Figure 1 illustrates these regions. Click for enlarged version.

Fig. 1 Physiographic Regions of Kansas
From the Kansas Geological Survey

Fig. 2 Map with counties where Red Hills
located. Modified by G.R. Corley. Map
courtesy of Kansas Geological Survey.

The physiographic regions are determined by: 1) predominate grasses, 2) climate, 3) types of agriculture, 4) altitude, and 5) an arbitrary cartographic line (Frye and Schoewe, 1953). The Red Hills region, also known as the Gyp or Gypsum Hills, is located in south-central Kansas. Included in this region partially or wholly are Meade, Clark, Barber, Comanche, Kingman, Kiowa, and Harper Counties. This region is noted for its rugged hills, buttes and mesas, red soils and gypsum deposits (Figures 3 and 4). Natural bridges occur in Barber County and Clark County is noted for two sinkholes, Big and Little Basin.

Fig. 3. Butte in Barber County.

Fig. 4. Permian red beds on Bouzidan Ranch.
Note layers of white gypsum in bed.

Return to top of page.

Description of Study Region

The United States is divided into three ecosystems domains: 1) The dry domain, 2) the humid temperate domain, and 3) the humid tropical domain (USDA). The Red Hills Region is in the dry domain. These domains are further divided into ecosystem provinces and divisions. Characteristics of the dry domain include annual loss of water by evaporation exceeds the annual water gain from precipitation. Boundaries for domains cannot be set on a specific value of annual precipitation. Permanent streams do not originate in dry climate zones normally.

There are 347,100 square kilometers (134,000 square miles) of land from the Canadian border through Oklahoma, including the high plains and central lowlands in the Great Plains Steppe Province (USDA). The characteristics of this province are mixed grasses, soils designated as mollisols, with small areas of entisols and vertisols. This area was once dominated large herds of bison (Bos bison). The American bison is now found only in parks or privately owned herds. A wide range of fauna occurs. Migrating waterfowl nest in the northern area of the region and there is an abundance of other birds and animals living in this dry climate. Kansas is further subdivided into physiographic regions. The Red Hills Physiographic Region is one of the 11 regions and located in south-central Kansas along the state line between Kansas and Oklahoma.

This region is dated from the Permian Period when several thousand feet of sandstones, red shales and siltstones were deposited (Buchanan, 1984). The hills are rugged and capped with layers of gypsum and dolomite and form butte-and-mesa topography. The Indians called this area the Medicine Hills and the river was known as the Medicine River as they considered the hills and river water to cure illnesses and cause wounds to heal rapidly (Wilson, 1978). The water in the streams and springs contained dissolved calcium and magnesium sulfates and has healing and therapeutic effects. Two large sinkholes in Clark County of special interest are Big and Little Basins. North of the Cimarron River is lowland known as the Englewood-Ashland Lowland and geologists believe this is a sinkhole covering a large area in Clark and Meade counties. The Red Hills Physiographic Region is the focus of this study.

Climate varies from the Canadian border to Oklahoma. Average annual temperature ranges from 4ºC (40ºF) in the north to 18ºC (65º) to the south; 13ºC (55ºF) to the east and 15ºC (60ºF) in the west (USDA). Precipitation varies from 380-770 mm (15-30 in.) over the Great Plains Steppe Province.

Agriculture in the Red Hills region includes dryland farming and some irrigation. The majority of crops are dryland and these include wheat, grain sorghum, soybeans, and hay (USDA). The major crops are hay, for livestock feed, and wheat, as a cash crop. Much of the Red Hills is not tillable ground and remains in pasture land. More than 200,000 head of cattle were pastured or in feedlots in this region in 2006.

Gypsum, an evaporite mineral, is abundant in the Red Hills. It occurs as selenite, satin spar, and rock gypsum. In Barber County the National Gypsum Company manufactures wallboard and other plaster products (Cyber Lodge Internet Service). Near Sun City, a mining operation provides the rock gypsum for the plaster industry.

Pronghorn antelope (Antilocapra americana) are found in the Red Hills. A herd of bison, owned by the Kansas Department of Wildlife and Parks (KDWP), is located in Big Basin Prairie Preserve in Clark County (KDWP). Big Basin is a circular depression about 1.61 k (1 mile) wide and 31 m (100 feet) deep. The walls are almost vertical and scattered over the floor of the basin are small ponds that hold water temporarily when it rains. The basin is bisected by U.S. Highway 283 and two thirds of the basin lies east of the highway. The eastern two-thirds of the basin is part of the 1,818 acre Big Basin Prairie Preserve managed by KDWP. The remaining one-third of Big Basin is owned by private landowners. Figure 5 was taken in Big Basin Prairie Preserve with the bison herd in the distance.

Fig. 5. Big Basin in Clark County

Located within the Big Basin Prairie Preserve is another basin known as Little Basin. It is much smaller than Big Basin and is about 256 m (280 yards) wide and 11 m (35 feet) deep. Located in one end of Little Basin appears to be another much smaller sink (Right of Arrow Figure 6). St. Jacob’s Well is located in the Little Basin. It is a hole of water 26 m (84 feet) wide and 18 m (58 feet) deep and has never been known to go dry.

Fig. 6. Little Basin, Clark County.

Fig. 7. St. Jacob's Well, Clark County.

The Red Hills is a mixed grass region including the tall grass a short grasses. Grasses found in this region include: big bluestem (Andropogon gerandii), blue gamma grass (Bouteloua gracilis), hairy gamma (Bouteloua hirsute), buffalo grass (Buchloë dactyloides), alkali or salt grass (Distichlis spicata), little bluestem (Schizachyrium scoparium), side oats gramma (Bouteloua curtipendula), sand bluestem (Andropogon hallii), and sand reed grass (Calamovilfa longifolia) (Lauver et al., 1999). These are the predominate grasses.

Fig. 8. Sage and prairie, Clark County.

Other vegetation in the Red Hills are forbs, trees, and scrub brush. Found growing in areas where grass is thin is the sand sagebrush (Artemisia filifolia) (Lauver et al., 1999). Purple poppy mallow (Callirhoe involucrate), heath aster (Callirhoe involucrate), evening primrose (Oenothera macrocarpa), sand dropseed (Sporobolus cryptandrus) and the broom snakeweed (Cutierrezia sarothrae) are forbs found in this region. Trees common to south central Kansas include the cottonwood (Populus deltrides), peach leaf willow (Salix amydalvides), the narrow leaf willow (Salix exigua), common hackberry (Celtis occidentalis), and the eastern red cedar (Juniperus virginiana). Shrubs and brush can be found in draws and close to water and some of the most common found are Chickasaw plum (Prunus angustifolia), smooth sumac (Rhus glabra), and buckbrush (Symphoricarpus occidentalis). All of this vegetation is used to determine a physiographic region.

The Red Hills region climate is dry and present are reptiles and arachnids adapted to dry climates. Fitch (1993) did a study on Kansas snakes and found the most common captured for the study in the region were: the prairie rattlesnake (Crotalus viridis), the eastern worm snake (Carphophis amoenus), the ring-necked snake (Diadophis punctatus), and the gopher snake (Pituophis catenifer). Another reptile is the Texas Horned Lizard (Phrynosoma cornutum). These small lizards, commonly called horned toads, can be found in the prairie grass pastures (Figure 9). A variety of insects and tarantulas (Aphonopelma sp.) are commonly found (Figure 10).

Fig. 9. Horned lizard, Kiowa County, by G. Corley.

Fig. 10. Tarantula, Clark County.

Fig. 11. Clark County State Fishing Lake, Note white mortar beds at the edge of High Plains Region on far side of lake.

Clark County State Fishing Lake is a 300 acre (122 hectare)lake in the Bluff Creek Canyon of Clark County, Figure 11 (KDWP). The mortar beds are visible at this site and are the escarpment boundary between the Red Hills and High Plains Region (Frye and Leonard, 1952). The spillway of the lake is cut down into the Permian red beds and gypsum deposits are visible in the banks and where the water has evaporated on the rocks around the water's edge. This lake is used recreationally and is managed by the Kansas Department of Wildlife and Parks.

Return to top of page.


Information was gathered from the Kansas Geological Survey website and a literature search of writings of early geologists and recent literature was reviewed. Permission was obtained from a rancher in Clark County to have access to his ranch to collect rock and mineral specimens and take photographs. Photographs were also taken along U.S. Highway 160 in Barber County. These photographs were taken with a digital Canon PowerShot A610 camera.

Return to top of page.

Literature Review

The physiographic subdivisions of Kansas have been changed over the past 101 years since Haworth (1896 and 1897) and Adams (1897-98 and 1902) wrote about these subdivisions. The number of physiographic regions has been designated from eight to twelve by different geologist. Adams (1902) proposed boundaries and characteristics of the divisions of Kansas and a brief description of each division. He proposed ten regions and the eastern third of the state were divided similarly to the present Kansas Geological Survey (KGS) with the exception of the different names. The greatest difference is seen in the Arkansas River Lowlands and the Wellington-McPherson Lowlands. Adams Great Bend Prairie included the McPherson Lowlands and extended almost to Dodge City in Ford County. The Wellington Lowlands was a part of the Oklahoma Prairie. The division between the Oklahoma Prairie and the Red Hills was the Gypsum Hills escarpment. Adams discussed the drainage of the Cimarron River, but did not specifically mention the Red Hills region.

Fig. 12. Surface Features of Kansas by Moore (Aber, 2007).
Click to enlarge map.

A surface feature map of Kansas in 1930 by Moore, illustrated eight regions (Aber, 2007). The Great Bend Prairie region included the Red Hills. The Glaciated Region of Kansas was not distinguished from the Osage Plains, but was included in it (Figure 12).

Fig. 13. Schoewe's Kansas physiograpic map, 1949 (Schoewe, 1949). Click to enlarge map.

The Kansas Physiographic Regions Map of Schoewe (1949) included both regions and subregions that vary slight from the present day KGS map. Schoewe had twelve regions and subregions. The Arkansas River Lowlands were separated into two subregions, the Finney Lowlands and the Great Bend Lowland. The KGS Wellington-McPherson Lowlands were separated into two subregions, the Wellington Lowlands and the McPherson Lowlands. The Red Hills or Cimarron Breaks division Schoewe considered being quite scenic (Figure 13).

Frye and Schoewe (1953) described how boundary lines of physiographic regions should have an internal homogeneity in the areas of fauna, flora, climate, soils, geology, and topography. These geologists believed setting boundary lines were difficult due to changes in land use, the changing climate, and the distribution of soil types, animal and plant patterns. They believed Kansas should have eight physiographic regions. Several of these regions were divided by escarpments. The present day Ozark Plateau was included in the Cherokee Lowlands. The Chautauqua Hills was integrated into the Osage Cuestas. The McPherson Lowlands were part of the Great Bend Region and extended only to the northeast corner of Ford County. The Wellington Lowlands were part of the Red Hills Region. These were the major differences seen between Frye and Schoewe’s map and the present day KGS map.

Fig. 14. Physiographic map proposed revisions by Aber and Aber (2007). Click to enlarge map.

In 1978 a physiographic map was completed by Wilson (Aber, 2007). The map presently used by the KGS is adapted from Wilson's map. Aber and Aber (2007) have proposed the following changes to the KGS map, dividing it into twelve regions (Figure 14). The Osage Plateau, Cherokee Lowlands, Osage Cuestas, Chautauqua Hills, Flint Hills, Red Hills, and High Plains would basically remain as presently denoted. The Arkansas River Lowlands would be changed to include the Wellington-McPherson Lowlands as these two regions have many similar characteristics: sand dunes and Quaternary alluvial deposits of sand, gravel and silt.

The greatest change would occur in the Smoky Hill region. It would be divided into three regions: 1). Smoky Hills, 2). Blue Hills, and 3). the Chalk Buttes. These changes in the physiographic regions were based on eight general characteristics of the regions.

  • Bedrock age and type
  • Surficial sediments
  • Landforms
  • Relief
  • Drainage
  • Natural vegetation
  • Land use
  • Special Conditions
These three areas are all Cretaceous deposits and were deposited at different times making the underlying bedrock and types different (Aber, 2007). The Smoky Hills are lower Cretaceous deposits and are characterized by deposits of sandstone. The Dakota Sandstone Formation is a rock resistant to erosion and forms escarpments, the hills are rugged, and there is high relief in this part of the state. The Blue Hills and the Chalk Buttes are upper Cretaceous deposits. The chalk erodes more easily and these hills are lower with gentle slopes and have more moderate relief than the Smoky Hills. Thick layers of chalk are the characteristics of the Chalk Buttes, while the Blue Hills has thinner chalk layers and shales. These characteristics of the three areas and a difference in vegetation coverage, drainage from perennial to intermittent streams, and different special conditions in each area separate them distinctly.

Return to top of page.

Geology of Red Hills

The dissected terrain of the Red Hills is associated with the retreating escarpments of the High Plains (Frye and Leonard, 1952). The scarp farthest west defines the edge of the High Plains and is capped in Clark County by the Ogallala Formation and in Comanche, Kingman, and Barber counties by early Pleistocene deposits. The secondary scarps and buttes are capped by Permian gypsum and siltstone locally, giving the area its characteristic appearance. The upper Permian rocks of the Red Hills Region are part of a 22 county area of south-central Kansas studied by Swineford (1955). Their color is derived from the hematite stain of mineral grains in the shale, siltstone, and sandstone. Coatings on detrial minerals and in colloidal solution from the Colorado and Oklahoma highlands are a probable source of the iron oxides. The Red Hills upper Permian age deposits of shale, siltstone, dolomite, salt and gypsum were laid between 248.2 to 290 million years ago (KGS, 1999). The lower Permian deposits were limestone, shale and chert forming the Flint Hills. The Permian lasted about 41.8 million years and seas covering Kansas rose and subsided depositing the dolomite, shale, and siltstone. Salt and gypsum were deposited when the sea water evaporated.

What is now the Permian Red Hills were then covered with deposits from the Triassic through the Tertiary periods. By the end of the Cretaceous period the inland sea stretching from the present day Gulf of Mexico to the Arctic Ocean had subsided due to the elevation of the land (Haworth, 1897). The mountains to the west in present day Colorado were elevated and previous drainage toward the inland sea from the east was reversed and water across Kansas flowed to the east-southeast. The land exposed from the sea was subject to erosion by wind and water. During the Tertiary and Pleistocene time erosion took place all across Kansas. Drainage and erosion was climate dependant as it is today with greater erosion in the wet periods by water and wind erosion in the dry periods. This created times when heavy rock, silt, and sand materials were moved by water and sand and soil moved by the wind and deposited.

This region is drained by four rivers: the Cimarron, Medicine Lodge, Salt Fork Arkansas, and the Chikaskia River. The tributaries of these rivers include Crooked Creek, two Bluff Creeks, Bear Creek, Mule Creek and Sandy Creek. Water from rivers flow into the Arkansas River in Oklahoma.

Two formations of the Permian red beds are significant in this region, the Day Creek Dolomite and the Blaine Formation. The Day Creek Dolomite is exposed in Clark County north of the Cimarron River and is noted here because it is restricted to Clark County (Swineford, 1955). Exposures occur along Krieger Creek and southeast into Harper and Woodward counties in Oklahoma. The Blaine Formation is a massive 15 m (50 feet) bed of gypsum and exposed in Barber, Comanche, and Kiowa counties. This Permian bed can be easily traced from Kansas through western Oklahoma, the Texas panhandle and into central northern Texas. It has several gypsum members and the thickest is the Medicine Lodge gypsum member as its lowest bed. It is 9 m (30 feet) thick and contains a dolomite base of 30 cm (1 foot). A layer of anhydrite 30 cm (1 foot) thick is within this member approximately 3 m (10 feet) from the base. Gypsum is mined from the Medicine Lodge member for the plaster industry.

Fossils are rare in the Permian red beds (Swineford, 1955). The Cyzicus, a brine shrimp, is restricted to the non-red bedding and found in the Wellington Shale east of the Red Hills. Plant remains, vertebrate fossils and tracks have not be observed or reported in the past according to Swineford. Fossils of the Pleistocene, Elepha primigenius, have been found in the Red Hills region in Clark County (Williston, 1895-96). Other late Tertiary and Pleistocene fossils of mastodons, camels, rhinoceroses, two and three toed horses, and shell parts of large turtles have been recovered (Pioneer Krier Museum). These fossils are displayed at Fort Hays State University Museum, the Smithsonian Institute Museum, the Pioneer Krier Museum, and in Europe.

Clark and Barber counties have geologic features connected and controlled by the Permian gypsum beds (Merriam and Mann, 1957). Sinks, caves, and natural bridges occur in the Red Hills Region. Sinks are classified as simple, complex, or coalescing and are either a solution-subsidence or solution-collapse type. Big Basin and Little Basin, Clark County, are solution-subsidence or solution-collapse types. A simple sink involves one incident of subsidence and deposits in the basin will dip toward the center. A complex sink has subsidence occurring more than one time and it affects the previous sink or sinks. Little Basin is an example as it contains St. Jacob’s Well and another area appearing to sink, Figure 6. Coalescing sinks occur when two or more sinks are joined together by erosion or the collapsing of the rims. The Ashland-Englewood Basin is an example of this classification. The solution-subsidence sink develops more slowly with downward movement and the solution-collapse sinks occur suddenly and draw more attention.

Big Basin has vertical walls and small depressions within it holding water for short periods of time (Merriam and Mann, 1957). It probably occurred several hundred to a few thousand years ago. Little Basin occurred about the same time and St. Jacob’s Well more recently. These sinks were created by water dissolving the gypsum and other soluble minerals in the Permian bed and the roof over the area weakening allowing the overburden to sink or collapse and the basin to develop. Comanche and Barber counties have small caves, sinks and natural brides because of solution of the Blaine gypsum (Merriam and Mann, 1957). A natural bridge over Bear Creek formed in Barber County and was known as the Sun City Natural Bridge. This bridge was 11 m (35 feet) wide with a span of 17 m (55 feet). It was formed by the solution of Permian gypsum as the water flowed through and developed the bridge over the creek. Continued erosion of Bear Creek and solution of the gypsum caused the natural bridge to collapse in 1962 (Charlton and Merriam, 2003).

Return to top of page.


The Red Hills region of Kansas is distinct and different from the other present 10 physiographic regions of Kansas. This region of upper Permian red beds is different geologically from the other major Permian deposit in Kansas, the lower Permian deposits of the Flint Hills Region. Because of its distinctive nature it will continue to remain a separate region, even if other regions in the state are changed with new boundaries and names.

Return to top of page.

Photo Gallery

Click on the small pictures for enlarged photograph.

Red Hills, Bouziden Ranch, Clark County.

Ravencraft, original ranch headquarters,
established 1886, Bouziden Ranch.

Site of military redoubt, Bouziden
Ranch, Clark County. Note prairie
grass and ditch around redoubt area.

Bluff Creek in Clark County.

Big Basin, Clark County.

Big Basin from rim bison
herd in distance.

Big Basin bison herd.

Clark County State Lake
with mortar beds visible on
opposite side of lake.

High Plains mortar bed at
Clark County State Lake.

Clark County State Lake
Spillway. Note white gypsum
evaporite on rocks.

Sink in bluff wall, Clark County.
Note syncline and dipping layers

Red soil, Clark County.

Gypsum layers in Barber County

Satin spar gypsum, Barber County.

Gypsum, Barber County.

Gypsum layers eroding
from hillside,
Barber County

Butte-and-mesa topography,
Barber County.

Permian red beds near Belvidere,
Kiowa County. Photo by G. Corley

Remnants Ogallala Formation
near Belvidere, Kiowa County.
Photo by G. Corley.

Return to top of page.


Aber, J.S. 2007. Kansas physiographic regions, ES 546 Field Geomorphology Syllabus, Emporia State University, Emporia, KS.

Aber, J.S. and Aber, S.W. 2007. Kansas physiographic regions: A reappraisal. Kansas Academy Science, annual meeting (poster).

Adams, G.I. 1897-1898. Physiography of southeastern Kansas. Transactions of the Annual Meetings of the Kansas Academy of Science, vol. 16, pp. 53-63.

Adams, G.I. 1902. Physiographic divisions of Kansas. Bulletin of the American Geographical Society, vol. XXXIV, No. 2.

Buchanan, Rex. 1984. Kansas geology, an introduction to landscapes, rocks, minerals, and fossils. University Press of Kansas, Lawrence, KS.

Charlton J. and Merriam, D. 2003. Ever changing landscape: Recent topographic landmark erosion in Kansas. Transactions of the Kansas Academy of Science, vol 106, no. 1/2, p. 29-39.

Cyber Lodge Internet Service, World Wide Web [retrieved 28 Nov. 2007].

Fitch, Henry. 1993. Relative abundance of snakes in Kansas. Transactions Kansas Academy of Science, vol. 96, p. 213-224.

Frye, J.C. and Leonard, A.B. 1952. Pleistocene geology of Kansas, Summary of Pleistocene drainage changes, World Wide Web [retrieved 20 Nov. 2007].

Frye, J.C. and Schoewe, W.H. 1953. The basis for physiographic subdivisions of Kansas. Transactions of the Kansas Academy of Science, vol. 56, no. 2, pp. 246-252.

Haworth, E. 1896. Physiographic features of the Carboniferous. University Geological Survey of Kansas, vol. 1, pp. 195-217.

Haworth, E. 1897. Physiography of western Kansas. University Geological Survey of Kansas, vol. 2, pp. 11-49.

Kansas Department of Wildlife and Parks. Big Basin Prairie Preserve Wildlife Area, World Wide Web [retrieved 28 Nov. 2007].

Kansas Department of Wildlife and Parks. Clark State Fishing Lake, World Wide Web [retrieved 21 Nov. 2007].

Kansas Geological Survey. Physiographic map of Kansas, World Wide Web [retrieved 10 Nov. 2007].

Kansas Geological Survey, 1999. Kansas Geologic Timetable, World Wide Web [retrieved 10 Nov. 2007].

Lauver, C.L., Kindscher, K., Faber-Langendoen, D., and Schneider. 1999. A classification of the natural vegetation of Kansas. The Southwestern Naturalist, 44 (4):421-443.

Merriam, D.F. and Mann, C.J. 1957. Sinkholes and related geologic features in Kansas. Transactions of the Kansas Academy of Science, vol. 60, no.3, p. 207-243.

Pioneer-Krier Museum, Ashland, Kansas. County History Home. [retrieved 6 Dec. 2007].

Schoewe, W. H. 1949. The geography of Kansas. Kansas Academy of Science Transactions, 52/3, pp. 261-333.

Swineford, Ada. 1955. Petrography of upper Permian rocks in south-central Kansas, World Wide Web [retrieved 20 Nov. 2007].

U.S.D.A. Forestry Service, Ecosystem Domains, World Wide Web [retrieved 22 Nov. 2007].

U.S.D.A. Forestry Service, Ecosystem Divisions, World Wide Web [retrieved 22 Nov. 2007].

U.S.D.A. Forestry Service, Ecosystem Provinces, World Wide Web [retrieved 22 Nov. 2007].

U.S.D.A. National Agricultural Statistics Service, Data and Statistics, World Wide Web [retrieved 28 Nov. 2007].

Williston, S.W. 1895-1896. The Pleistocene of Kansas. Transactions of the Kansas Academy of Science, vol. XV, p. 90-95.

Wilson, F.W. 1978. Kansas landscapes, A geologic diary. Kansas Geological Survey, Lawrence, KS.

Return to top of page.

I want to thank rancher Rhett Bouziden, Ashland, Kansas, for granting permission to take photographs and collect specimens on his ranch and Gaylette Conard for taking the photographs on this website. All photographs are by Gaylette Conard unless stated otherwise.

This webpage was created to meet the requirements of ES 546 Field Geomorphology at Emporia State University, Emporia, Kansas, and is the property of the author. For more information contact the author: Gayla R. Corley

Created 27 November, 2007, for the Earth Science Department, Emporia State University:, at Emporia State University, Emporia, KS Latest update December 6, 2007.

Return to top of page.