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Ingalls Area Hydrology

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Geology in Relation to Ground Water

Cretaceous System

Gulfian Series

Carlile Shale

Character—The Carlile shale consists predominantly of darkblue to black calcareous fissile clay shale, chalky shale, and thin beds of chalky limestone. It is composed of two members, the Fairport chalky shale below and the Blue Hill shale above, which elsewhere contains the Codell sandstone zone at the top.

The Fairport chalky shale member constitutes the lower third of the Carlile shale and consists predominantly of dark-gray to black and yellow-tan calcareous shale containing some gray limestone, flakes of calcite, and hard fine-grained concretions. The Blue Hill shale member constitutes about the upper two-thirds of the formation. The upper part of this member is exposed in a strip along Pawnee Valley several miles north of the area considered in this report. The member consists of dark-gray, bluish-black, and black non calcareous shale containing thin seams of gypsum, selenite crystals, and in the upper part a zone of large septarian concretions.

At the top of the Carlile shale in other parts of Kansas is a sandy zone, the Codell sandstone zone, consisting of fine-grained silty sandstone and sandy shale. The Codell sandstone zone is missing in the Ingalls area and presumably was deposited but later removed by erosion before deposition of the Ogallala formation.

Distribution and thickness—The Carlile shale does not crop out in the Ingalls area, but it underlies the area and has a maximum thickness of 300 feet (Latta, 1944). Of 32 test holes drilled by the Bureau of Reclamation, 31 penetrated a dark-gray calcareous clay shale, which is probably the Carlile shale. One test hole did not penetrate the entire thickness of younger sediments overlying the Carlile shale.

Water supply—Because of its low permeability, the Carlile shale yields little or no water; no wells in the area are known to obtain water from it.

Tertiary System

Pliocene Series

Ogallala Formation

Character—Unconformably overlying the Cretaceous shales is a thick sequence of clay, calcareous silt, and sand and gravel of the Ogallala formation. In general, the materials making up the Ogallala formation are poorly sorted, and the lithology changes vertically within short distances. Most studies of the Ogallala formation indicate that the deposits are lenticular, but in the relatively small Ingalls area the logs prepared from drill cuttings and used in the cross sections in Plates 2 and 3 show fair lateral continuity of beds.

Nearly all the 32 test holes drilled by the Bureau of Reclamation penetrated some clay beds in the lower half of the Ogallala formation. These beds consist of tan, gray, and greenish-gray non-calcareous clay containing streaks of silt and fine sand. The thickness of the clay beds ranges from a few inches in some places to as much as 26 feet in test hole 25-30-12dd. Several test holes penetrated 5 to 20 feet of clay.

Silts containing minor amounts of clay and much fine to medium sand compose most of the fine materials of the Ogallala formation. Beds of tan, pink, and gray silt ranging from a few inches to as much as 60 feet thick are common throughout the area. Many silt beds are heavily impregnated with calcium carbonate, which colors them gray white to light gray.

Sand is the most abundant material in the Ogallala and is found throughout the formation. Sand beds are not common, but where present they generally contain silt, are poorly sorted, and range from fine to very coarse. The sand consists predominantly of angular to subangular quartz grains but contains some feldspar grains and dark minerals. Mica is present in most sand beds.

The coarse material of the Ogallala formation is fine to coarse gravel, generally containing sand and some silt and clay. Fine to medium gravel predominates, but action of the drill during test drilling indicates the presence of very coarse gravel that was not brought to the surface by the drilling fluid. Gravel is present throughout the formation but is generally most abundant in the lower part. At or near the base of the formation it generally contains abundant pebbles of weathered Cretaceous chalk, limestone, sandstone, and ironstone, indicating local origin. Higher in the formation the gravel is arkosic, indicating a source in the Rocky Mountain area.

Caliche is common throughout the Ogallala formation and occurs as cementing material, nodules, and small pipe-like concretions. Only 2 test holes drilled by the Bureau of Reclamation penetrated massive caliche; 26-31-1bb penetrated 13 feet and 26-28-1bb penetrated 12.4 feet. In both test holes the massive caliche was near the base of the formation. Thin lime-cemented zones of silt and sand a few inches to 1 foot thick were common in all test holes.

Distribution and thickness—The Ogallala formation is exposed along the north bluff of the Arkansas River valley, and test holes penetrated it beneath younger sediments throughout the area. Because of lithologic similarity, the contact between the Ogallala formation and the overlying younger deposits was difficult to determine in test holes, and only an approximate thickness can be given for the formation in this area. Test hole 26-28-1bb penetrated more than 300 feet of material believed to be of the Ogallala formation. South of Arkansas River part of the Ogallala formation was removed by erosion during Pleistocene time, and the part remaining was subsequently covered by younger deposits. In part of the area south of the river the Ogallala formation may be less than 75 feet thick.

Water supply—In the upland north of Arkansas River all wells obtain water from the Ogallala formation, the sands and gravels in most places being capable of yielding large supplies. Yields range from a few gallons per minute from stock and domestic wells to as much as 1,600 gpm from irrigation well 25-29-14ab. North of Arkansas Valley in the Ingalls area 21 irrigation wells produce water from the Ogallala formation. Further development of water from this formation for irrigation in the area seems feasible.

In the Arkansas River valley and the area south of the valley younger saturated deposits overlie the Ogallala formation, and only one well, 25-29-27 cc2, is known to obtain water from the Ogallala. This well produces water from both the Ogallala formation and the alluvium of Arkansas River. In the vicinity of Pierceville and as far east as Charleston, clay, silt, and fine sand compose the bulk of the Ogallala formation; hence yields are not adequate for extensive irrigation, although stock and domestic supplies are available.

Quaternary System

Pleistocene Series

Meade Group

Character—South of Arkansas River, in the area covered by dune sand, test holes penetrated a thick deposit of sand and gravel containing minor amounts of silt overlying the Ogallala formation. These deposits are not exposed in the Ingalls area, but test-hole cuttings indicate that the deposits are poorly sorted and contain abundant coarse arkosic gravel. The deposits differ from the Ogallala formation in several ways, and because they are in the same relative position as known Kansan deposits in southern Gray County (Latta, 1944; Frye, 1942) they are classified tentatively as of late Kansan age.

The fine materials in the deposits of late Kansan age consist of silt and sandy silt and are mostly in the upper part. The silt is generally tan, but where calcium carbonate is present in large quantity it ranges from gray to near white. Test hole 26-28-36cc penetrated a black silt at a depth of 89 feet that contained many fragments of fossil mollusk shells, none of which was complete enough for identification. Nearly all the silt penetrated in the Kansan deposits is calcareous, but heavy calcareous silt typical of the Ogallala formation is absent.

Sand beds in the Kansan deposits cannot be distinguished lithologically from those of the Ogallala formation. Few sand beds were penetrated in test holes, but where present they were in the upper part of the formation.

Fine to very coarse gravel containing sand and thin silt beds composes the bulk of the Kansan deposits. The gravel is made up chiefly of granite, feldspar, and quartz pebbles and, in general, is coarser than gravel penetrated in the Ogallala formation. Pebbles of sandstone, limestone, chalk, and ironstone, such as are abundant in the basal gravels of the Ogallala formation, were not present in the Kansan deposits.

Some caliche is present throughout the deposits but in very minor amounts almost confined to the upper part. A few thin lime-cemented streaks are present throughout the sand and gravel deposits but not in amounts comparable to those in the Ogallala formation.

Distribution and thickness—The Kansan deposits probably underlie all the area south of the Arkansas River valley. If present under the younger alluvial deposits of the valley, they were not recognized during the test drilling. These deposits are topographically lower than the surface of the Ogallala formation north of the river, and if present north of Arkansas River they were not recognized.

The thickness of the Kansan deposits ranges from a featheredge near the Arkansas River valley to 147 feet (or more) near the southern edge of the Ingalls area. The maximum thickness was penetrated in test hole 26-28-29bb, where 135 feet of sand and coarse gravel was overlain by 12 feet of silt between depths of 32 and 179 feet.

Water supply—The area south of Arkansas River that is underlain by Kansan deposits is used mostly for grazing because the sand dunes make it unsuitable for farming. As a result, few wells other than stock and domestic wells are drilled in the area, and the water in the formation is undeveloped. Only three irrigation wells are known to penetrate the formation; two of these, wells 26-31-4cc and 26-31-12cc, reportedly yielded 1,800 gpm each when test pumped. Large water supplies from wells seem to be obtainable in most of the area underlain by Kansan deposits.

Sanborn Group

No attempt has been made to subdivide the Sanborn group in the Ingalls area. The undifferentiated deposits of the Sanborn group (Table 1) described in this report are exposed in the upland north of Arkansas River and underlie the dune sand south of the river. The deposits north of Arkansas River are topographically higher and, except for some water-laid sands and silts near the base, are eolian in origin. South of Arkansas River the deposits of the Sanborn group are probably water laid.

Character—The upland north of Arkansas River is mantled by deposits of silt, sandy silt, and sand, which are late Pleistocene in age. These deposits overlie very calcareous sandy silts of the Ogallala formation and are difficult to distinguish from the Ogallala in test-hole drill cuttings. The materials composing the Sanborn group north of Arkansas River are calcareous silt, sandy silt, and some sand. The color of the silt ranges from tan to gray tan, according to the amount of calcium carbonate present. The silts commonly become more sandy with depth and in many places grade into thin beds of fine to medium sand near the base.

South of the Arkansas Valley, in the area covered by dune sand, a sequence of silts, sandy silts, and sand of late Pleistocene age overlies deposits of gravel, sand, and silt tentatively classified as of late Kansan age. Cross section F-F' (Plate 3) indicates two cycles of deposition, each consisting of sand that grades upward into silt. The cross sections in Plate 2 indicate that these deposits have been beveled by erosion and could have been the source of the overlying dune sand.

The fine materials composing the Sanborn group south of the Arkansas Valley consist of calcareous silt, sandy silt, and sand. The silts are tan, gray tan, gray white, and gray green, and generally grade downward into sand. The sand is generally poorly sorted, ranging from very fine to coarse, but is predominantly fine to medium. It consists principally of subangular to angular grains of quartz but contains feldspar and dark minerals. No gravel was penetrated in the Sanborn group during test drilling.

Distribution and thickness—Deposits of the Sanborn group underlie the surface of the upland north of Arkansas River in the Ingalls area. South of the river these deposits are covered by dune sand, but they are continuous throughout the area except along the southern edge of the valley where they have been removed by erosion or covered by younger terrace deposits.

Contacts between the Sanborn group and underlying older sediments are difficult to distinguish in test holes because of similarities in lithology; therefore the thicknesses given here are only approximate. North of Arkansas River, deposits of the Sanborn group are 15 to 30 feet thick. South of the river the thickness ranges from a featheredge to as much as 65 feet but averages about 35 feet.

Water supply—In the Ingalls area the deposits of the Sanborn group, except: the terrace deposits south of" Arkansas River; lie above the water table and do not yield water to wells.

Terrace Deposits

Character—The deposits forming the prominent terrace 20 to 25 feet above the floodplain south of Arkansas River are probably of late Wisconsinan age and are included in the Sanborn group. These deposits are well exposed in gravel pits near Pierceville and Cimarron. They consist of unconsolidated crossbedded fine sand to large cobbles, which in the pit near Pierceville are overlain by sandy silt containing abundant invertebrate fossils. Sand and gravel beds are composed chiefly of subrounded to well-rounded quartz but contain some feldspar and dark minerals. Pebbles of quartz, feldspar, granite, other igneous rocks, and "mortar bed" compose the coarser gravels. Many of the pebbles in the coarse gravels are 2 to 4 inches in diameter, and some angular "mortar bed" blocks are as much as 8 inches long.

Distribution and thickness—Terrace deposits border the floodplain of Arkansas River throughout the Ingalls area and form an almost continuous scarp along the south edge of the floodplain. Remnants of the terrace Occur north of the river and are well exposed in a draw about 1.4 miles west of Ingalls. The thickness of the terrace gravels is known from two test holes: 25-31-22bb penetrated 25.5 feet of sand and gravel and 25-31-24dd penetrated 21.6 feet of sand and gravel.

Water supply—The upper part of the terrace gravels is above the water table and does not yield water to wells. The basal part, however, is below the water table and supplies water to a few stock wells in the area. An abandoned gravel pit in the terrace deposits south of Cimarron, 26-28-14dc, has been excavated below the water table, and the water is used as an irrigation supply.

Dune Sand

Dune sand of Quaternary age mantles the area south of Arkansas Valley. It is composed predominantly of fine- to medium-grained quartz sand but contains some silt and some coarse sand. The sand forms small hills that average 30 feet in height. Most of the sand hills are covered by vegetation, but locally small areas of bare sand are subjected to wind action. Smith (1940, p. 127-128, 153- 168) gives an excellent description of the dune sand in southwestern Kansas, and the reader is referred to his paper for further details.

No wells obtain water from the dune sand, because it lies above the water table. Because the sand is loose and permeable, it serves as an important catchment medium for precipitation. Although recharge to the ground-water reservoir from the sand dunes is retarded by underlying silt, the dunes hold precipitation in the area for a time sufficient to allow downward percolation that results in a recharge rate greater than in adjacent areas.


Character—Deposits of Recent alluvium underlie the floodplain of Arkansas River in the Ingalls area. The deposits of the lower terrace, which stands 4 to 6 feet above the floodplain, are also classified as Recent alluvium.

The alluvium consists of stream-laid deposits that range from clayey silt to very coarse gravel. The silt and clay beds are in the upper few feet of the alluvium. These silts and clays, which range from light gray to black, are generally sandy, and locally they contain abundant invertebrate shells. The sands of the alluvium, which range from tan to gray, are composed of fine to coarse grains of quartz and minor amounts of feldspar and dark minerals. The gravels, which compose the bulk of the alluvium, range from fine to very coarse but are predominantly fine to medium. They are poorly sorted and generally contain sand. The gravels consist chiefly of subangular to rounded quartz grains. The coarser gravels are mostly well-rounded pebbles of feldspar, granite, and other igneous rocks.

Distribution and thickness—The width of the alluvium of Arkansas Valley ranges from about 1 mile at Pierceville to H miles at Cimarron, and averages approximately 1 1/4 miles. The thickness of the alluvium varies from place to place but averages 35 feet in the deeper parts of the fill.

Water supply—The sands and gravels of the alluvium are the most permeable water-bearing deposits in the Ingalls area and are the source of most irrigation, stock, and domestic supplies in the valley. Yields range from a few gallons per minute from stock and domestic wells to as much as 2,500 gpm from an irrigation installation.

Irrigation in the Ingalls Area

Extent of Irrigation

Both surface water and ground water are used for irrigation in the Ingalls area. Plate 1 shows the points of diversion of surface water from Arkansas River and the locations of irrigation wells.

According to the records of the Division of Water Resources of the State Board of Agriculture, 2,470 acre-feet of surface water from Arkansas River and 12,045 acre-feet of ground water have been appropriated in the Ingalls area; 6,415 acre-feet is pumped from wells in the Arkansas Valley and 5,630 acre-feet from wells in the upland. Of the 5,630 acre-feet, about 1,560 acre-feet is pumped from wells within 4 miles of Arkansas River, and about 4,070 acre-feet from wells 4 to 14 miles from the river.

In the Ingalls area the total amount of land irrigated is 7,420 acres, of which 1,502 acres is irrigated with surface water from Arkansas River and 5,918 acres with ground water. Of the 5,918 acres irrigated with ground water, 2,240 acres is in the Arkansas Valley, 805 acres in the upland within 4 miles of the river, and 2,873 acres in the upland 4 to 14 miles from the river.

Yields of Irrigation Wells and Types of Power Used for Pumping

The yields of irrigation wells in the Ingalls area range from about 100 to 2,500 gpm. Most of the wells are in the Arkansas River valley, and many in the alluvium constitute what are known locally as batteries of wells-3 to 5 closely spaced wells pumped by one pump. Some of these installations are driven by gasoline or diesel engines and some are driven by electric motors. The battery-type wells have a wide range in yield, which depends on the permeability of the water-bearing materials and on the number of wells connected to the system. The yield of a battery system does not always increase in proportion to the number of wells in the system. Mutual interference between the wells may reduce the average yield per well below that from anyone well alone. The greater the distance between wells the less the mutual interference. , Most of the battery-type systems in this area yield at least 1,500 gpm. A few shallow wells in the valley are single-cased wells pumped by electric turbines. The yields of the upland wells range from about 500 to 1,600 gpm and average about 1,000 gpm. The wells are deep and are pumped by turbine pumps, most of which are driven by diesel motors.

Depths and Diameters of Irrigation Wells

Irrigation wells in the Arkansas River valley range in depth from 25 to 50 feet and average about 30 feet; they range In diameter from 15 to 18 inches. One well (25-29-27cc2) is 180 feet deep and yields about 1,400 gpm from both the alluvium and the underlying Ogallala formation.

The upland irrigation wells range in depth from 150 to 310 feet. These wells generally are cased with 16- to 18-inch pipe and are gravel packed. Some of the wells are screened throughout the saturated water-bearing material, whereas other wells are screened only in the zones of permeable sand and gravel.

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Kansas Geological Survey, Geology
Placed on web Sept. 10, 2017; originally published July, 1958.
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