Ogallala formation

In most of the aquifer area, the Ogallala Formation of Miocene age and overlying hydraulically connected Quaternary deposits, if present, are the principal geologic units in the aquifer. In northwestern Nebraska, south central South Dakota, and southeastern Wyoming, the fractured part of the Brule Formation or the Arikaree Group, is the ...

The Ogallala Formation in southeastern New Mexico (i.e., the part that is bounded on the west by the Mescalero Ridge) is almost entirely eolian, and paleogradients (and therefore tilting) have not been estimated. Duller et al. (2012) found that in the central Great Plains, tilting may have occurred ca. 6-3.7 Ma.Origin of the Ogallala. The Ogallala formation in Texas is the southernmost extension of the major water-bearing unit underlying the physiographic province of North America. It was named in 1898 by N.H. Darton for the town of Ogallala, Nebraska, near where the formation was discovered.Ogallala Formation, and locally it is as much as 27 thick. The eolian sedinents generally are finer grained to the northeast, indicating that they were derivedOgallala formation. Divisible into "cap rock bed," Burge sands, and Valentine beds. How deep is Ogallala Aquifer? The saturated thickness of the Ogallala aquifer in the North Plains Groundwater Conservation District ranges from 10 to over 460 feet with an estimated District average of 180 feet. The depth from land surface to the base of the ...The geologic and hydrogeologic characteristics of Tertiary lithostratigraphic units (Ogallala Formation and White River Group) that typically compose or underlie the High Plains aquifer system in southeastern Wyoming were described physically and chemically, and evaluated at a location on the Belvoir Ranch in Laramie County, Wyoming.The Ogallala aquifer is a sandstone formation that underlies some 583,000 square kilometers of land extending from northwestern Texas to southern South Dakota. Water from rains and melting snows has been accumulating in the Ogallala for the past 30,000 years. Estimates indicate that the aquifer contains enough water to fill Lake Huron, but ...

Spatial patterns of lithium, fluoride, nitrate, chloride and bromide in the Ogallala Aquifer of northwestern Texas were mapped and evaluated. Solute concentrations and depths were compiled for 705 water wells sampled between 2008 and 2014. Lithium concentrations were high relative to typical groundwater; median and maximum concentrations were 66.8 and 2,790 ug/L, respectively. Almost half of ...Aquifers are underground layers of porous and permeable rock or unconsolidated sediment, such as sand and gravel, that hold water. Porous means that rocks contain pores, or holes, and permeable means the pores are interconnected in a way that allows water to flow from pore to pore. Spaces containing water in sand and gravel or loosely consolidated rock can be …The Ogallala Formation in Kansas includes strata of Miocene and earliest Pliocene age, revising earlier correlation to the Pliocene only (Zeller, 1968). The Kansas Geological Survey is abandoning use of the term "Tertiary," to be replaced by the term "Neogene." International stage boundaries for the Neogene have not been established in Kansas.The Ogallala Formation in Central North America. The Ogallala Formation was named by Darton (1899) from a locality in southwestern Nebraska that he later (1920) referred to as Ogallala Station. Elias (1931, 1932, 1935, 1942) made detailed studies of the Ogallala in western Kansas and described fossil endocarps, nutlets, and anthoecia from the ...The Ogallala Formation was named by Darton in 1899 from outcrops in Keith County, Nebraska. These beds had previously been referred to as part of the Loup Fork Formation, now an obsolete term. Darton considered the Ogallala to be equivalent, at least in part, to the "mortar beds," "tertiary grit," and "magnesia beds" of Kansas.The Ogallala Formation is the principal water-bearing geologic unit of the central High Plains aquifer (Gutentag and others, 1984; Ryder, 1996); historically, the High Plains aquifer system was often referred to as the “Ogallala aquifer” throughout its extent in reference to the predominant water-bearing unit of the aquifer system, the ...is the Ogallala Formation of Tertiary age. The Ogallala Formation is composed of sediments eroded from the ancestral Rocky Mountains by streams and wind. The dominant mode of deposition was by braided streams that coalesced to form broad alluvial fans (Gutentag and others, 1984). The Ogallala Formation consists of semi-consolidated layers ofThe Neogene Ogallala Formation underlies much of the High Plains physiographic region of the North American Great Plains (Fig. 1) and is the primary water bearing unit of the High Plains aquifer—one of the world's largest freshwater aquifers providing nearly 30% of groundwater in the United States (Dennehy et al., 2002).Groundwater withdrawals in some areas have greatly exceeded local ...

The upper Tertiary Ogallala Formation in original or reworked form has been suggested as the source of the dune sand by Lugn (1935, 1960, 1962). Stanley and Wayne (1972) and Reed and Dreeszen (1965), among others, suggested a lower Pleistocene alluvial source. We conducted a mineralogic study of 7 dune and inter­Origin of the Ogallala Aquifer. The Ogallala formation in Texas is the southernmost extension of the major water-bearing unit underlying the physiographic province of North America. It was named in 1898 by N.H. Darton for the town of Ogallala, Nebraska, near where the formation as discovered.The Ogallala Formation in Kansas is divided into three members which, in ascending order, are the Valentine, Ash Hollow, and Kimball. A thin, discontinuous pisolitic limestone, 1 to 3 feet thick, commonly occurs as the topmost bed of the Ogallala. No attempt was made to divide the Ogallala Formation in Trego County, and it is shown on …Opalized fossil bones and shells of diatoms are found in the Ogallala Formation, as is a green opal that acts as a cement in hard, erosion-resistant sandstones. Chemical …Ogallala-High Plains Aquifer Information. This page specifically addresses issues relevant to the western Kansas (Ogallala) portion of the High Plains aquifer, including Groundwater Management Districts 1, 3, and 4, and the adjacent portions of the aquifer. A primary focus of interest is the issue of declining water levels and the implications for long-term water use and management.Ogallala Group or Formation (Miocene) at surface, covers < 0.1 % of this area. Silt, sand, sandstone, gravel and conglomerate. Predominantly interfingered fine- to coarse grained, poorly sorted, arkosic, fluvial deposits of light-gray, light-olive-gray, and grayish-green calcareous silt and sand, and locally poorly consolidated conglomerate ...

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The Ogallala Formation was named by Darton (1899) from a locality in southwestern Nebraska that he later (1920) referred to as Ogallala Station. Elias (1931, 1932, 1935, 1942) made detailed studies of the Ogallala in western Kansas and described fossil endocarps, nutlets, and anthoecia from the formation while Lugn (1938, 1939) studied the ...Of these, the Ogallala aquifer underlies most of western Kansas and consists mainly of the Ogallala Formation, a geologic unit that formed from sediment eroded off the uplifting Rocky Mountains.The Ogallala formation consists of clay, silt, sandy silt, caliche, and cross-bedded sand and gravel (pl. 11B) which locally is cemented by calcium carbonate to a hard, "mortar bed" type of rock. A generalized section of the Ogallala formation is shown in figure 12B. Channel sands and gravels typically occur at the base and are quite variable ...Pliocene Ogallala Formation of Trego County, Kansas may be referable to Regina. PERTINENT LITERATURE. General accounts of the four species are in Wright and Wright (1957), Emst and Barbour (1989) and Emst and Emst (2003). Important life history studies include those of Hall (1969), Branson and Baker (1974), FranzBlack Mesa is a mesa located in an area covering parts of the U.S. states of Colorado, New Mexico, and Oklahoma.It extends from Mesa de Maya, Colorado southeasterly 28 miles (45 km) crossing into the northeast corner of New Mexico, and ending in the Oklahoma panhandle along the north bank of the Cimarron River at its confluence with the North …

Between 1950 and 2013, the water levels dropped over 250 feet in an Ogallala well near Lubbock, Texas. The aquifer has seen more moderate declines elsewhere, but it’s causing problems for cities, well owners and irrigators alike. Oklahoma only permits its irrigators enough groundwater to cover each acre of their land with 2 feet …Ogallala Group or Formation (Miocene) at surface, covers 63 % of this area. Silt, sand, sandstone, gravel and conglomerate. Predominantly interfingered fine- to coarse grained, poorly sorted, arkosic, fluvial deposits of light-gray, light-olive-gray, and grayish-green calcareous silt and sand, and locally poorly consolidated conglomerate, sandstone, and siltstone. Although the ground water in the Ogallala Formation in the Southern High Plains is common to both Texas and New Mexico, the State laws concerning ownership of the water are different. The New Mexico statutes provide that all under­ ground waters of the State belong to the public and are subject to appropriation for beneficialA. GENERAL GEOLOGY, STRATIGRAPHY, AND HYDROLOGY The Ogallala Formation in Texas is the southernmost extension of the major water-bearing unit underlying the physiographic province of North America. It was named by Darton (1898) for the town of Ogallala, Nebraska, near the type locality. Following the Laramide revolution in which the southern Rocky Mountains were uplifted…Researchers have found just 12 people are responsible for the bulk of the misleading claims and outright lies about COVID-19 vaccines that proliferate on Facebook, Instagram and Twitter. "The ...The upper Tertiary Ogallala Formation contains the Ogallala (High Plains) aquifer, which is the major source of water for agricultural and domestic use on the Southern High Plains of Texas and New Mexico. Locally, perched aquifers overlie the Ogallala aquifer.The Tertiary Ogallala Formation directly overlies the Permian red beds, although Triassic sedimentary rocks are present in the southwestern part of Lake Meredith NRA. The approximately 10-million-year-old Ogallala Formation is much younger than the underlying rocks, and sits atop a regional uncomformity, or period of missing time. ...The Ogallala Formation is an expansive wedge of sand, gravel, silt, and clay that was eroded off the Rocky Mountains and then carried in and deposited by streams millions of years ago. At Point of Rocks, the sediment has been cemented into calcrete, which overlies older Permian -age beds of shale , siltstone, and sandstone .A late Cenozoic uplift of the Rocky Mountains led to the deposition of a vast fan of eroded sediment to their east, forming the Ogallala Formation that covers much of the Panhandle. Most of the state's current stream valleys and canyons date from the Pleistocene to the present, as the final geologic shaping of the state.and Becker, 1999). The Neogene Ogallala Formation and Triassic Dockum Group form shallow aquifers, which are underlain by thick Permian evaporites (Table 1 and Fig. 2). The unconfined Ogallala aquifer, which is the main water supply unit for the Southern High Plains, consists of fluvial sediments and fine-grained eolian silts and clays (Fig. 2).Ogallala Group or Formation (Miocene) at surface, covers < 0.1 % of this area. Silt, sand, sandstone, gravel and conglomerate. Predominantly interfingered fine- to coarse grained, poorly sorted, arkosic, fluvial deposits of light-gray, light-olive-gray, and grayish-green calcareous silt and sand, and locally poorly consolidated conglomerate ...

Stratigraphy. The Ogallala of northern Kansas meets all the stated requirements of a formation (Ashley and others, 1933). Although it contains a wide range of lithologic types, it is essentially a continuous blanket of alluvium that may be regarded as "homogeneous in its heterogeneity"; it is considered a conformable sequence, as the multitude ...

The Ogallala Formation (Neogene) is a widespread syntectonic alluvial apron that was shed eastward from the Rio Grande rift and related uplifts in Colorado and New Mexico during Basin and Range extension. In the Texas Panhandle, the Ogallala completely buried Ancestral Rocky Mountain (Pennsylvanian) structures. ...The Ogallala Formation (originally spelled Ogalalla) was named and first described by N. H. Darton in 1899 from its occurrence in the territory occupied by the Ogalalla Indians in southwest Nebraska and adjacent parts of Kansas. In his original description, Darton did not designate a type section but later (Darton, 1920) he ...The sediments deposited in the High Plains comprise the geologic formations of the Ogallala Group, which record this uplift event (Fig. 1a).Sediments were deposited in a braided river environment ...Between 1950 and 2013, the water levels dropped over 250 feet in an Ogallala well near Lubbock, Texas. The aquifer has seen more moderate declines elsewhere, but it’s causing problems for cities, well owners and irrigators alike. Oklahoma only permits its irrigators enough groundwater to cover each acre of their land with 2 feet …The Ogallala formation in Texas was described by Seni (1980) as a series of coalescing, humid type alluvial fans for a depositional model. The Ogallala Aquifer is an exhaustible resource (Osborn ...the contact between the Ogallala and pre-Ogallala (probably Brule) Formations exposed on the east side of Rush Creek. Beds of dilt, sand, siltstone, and volcanic ash in the area locally dip to the northwest at angles of up to 8g0. The contact between the two formations cannot be seen on the west side ofThe Loup Fork formation of Hayden, Leidy, Marsh, Cope and in part of Scott, Hatcher arid Osborn, may be regarded as corresponding to the Ogallala of Darton. To this formation, also, belongs the Republican river formation of Osborn (1910, p. 348) and part of the Snake creek formation of Cook and Matthew (1924).

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But farmers are pulling water out of the Ogallala faster than rain and snow can recharge it. Between 1900 and 2008 they drained some 89 trillion gallons from the aquifer - equivalent to two ...The smallest video file formats are WMV, FLV, MPEG-4 and RealVideo. These formats can be used to create videos or to stream them.The Ogallala formation of Tertiary (Pliocene) age unconformably overlies the Niobrara throughout these two counties (Pl. 5B). The Ogallala crops out in several places, the best exposures being along Ladder and White Woman Creeks. The undissected plains surface in the area is mantled by the wind-blown silt (loess) of the Sanborn formation of ...Tweet. The Ogallala Aquifer is a shallow table aquifer that sits under eight states ranging from South Dakota south to Texas and New Mexico. It is a major source of irrigation water throughout the region. Formation of the Ogallala Aquifer. Before the Aquifer formed, the land now known as the Great Plains looked nothing like it does now.the Ogallala formation varies in about the same proportion as the volume of water in storage. Nebraska with 64,400 square miles and Texas with 36,080 are the largest. New Mexico, Oklahoma, South Dakota, and Wyoming all have less than 10,000 square miles of surface area underlain by the Ogallala.7 Table 1: Characteristics of the High Plains Aquifer.The smallest video file formats are WMV, FLV, MPEG-4 and RealVideo. These formats can be used to create videos or to stream them.The Ogallala Formation crops out and is locally called the Ogallala aquifer, a convention followed in this report. The underlying White River Group is also an aquifer and, by the same convention, is referred to as the White River aquifer in this report.Ogallala formation. Calcareous grit or soft limestone, sandy clay, and sand, with basal conglomerate at many places. Of late Tertiary (Pliocene?) age. Thickness 150 … ….

The Ogallala Formation consists mostly of coarse sedimentary rocks in its lower sections, which grade upward into finer-grained lithologies. The water-permeated ...How Long Ago Was The Ogallala Aquifer Formed? Advertisements. The principal sediments and rocks of the aquifer range in age from 33 million years old to sediments being deposited today, but the majority is less than 12 million years old. Much of the aquifer is composed of the Ogallala Group or Formation.A 2022 report on the town’s underground water supply, the Ogallala aquifer — the same aquifer Lea County uses — shows the aquifer has dropped 112 feet since 1970. So could Hobbs and Lea County end up in the same situation at Portales? Not any time soon, said Tim Woomer, City of Hobbs public works director.Deposits of the Ogallala Formation lie to the north and cast of the buried ridge, while deposits of the ancestral Pecos River (variously 2. 09/18/2003 08:37 505-830-9528 FRAMATOME AW' MtAIO r&K- It .1 mapped as "Cenozoic Basin Iill, Gatufia Formation, or Ogallala Formation) lie to the south andthe Ogallala Formation, from 27,160 to 35,000 B.P.; and on caliches from 2 to 10 ft below the top of the Ogallala (Zones 2-4), from 30,880 to 43,100 B.P. The radio-carbon dates are apparent ages and do not indicate the time of initial deposition of the caliche. The dates reflect modifications of the calcium carbonate by events during lateLate Miocene (10 to 7 Ma ago) floras from five geographically distinct sites in the Ogallala Formation are described and compared: the Poison Ivy and Russ's floras from Nebraska, the Minium and ...The Ogallala Formation of late Miocene to early Pliocene age consists of heterogeneous sequen-ces of coarse-grained sand and gravel in the lower part, grading upward into clay, silt, and fine sand. In Texas, the Panhandle is the most extensive region irrigated with groundwater. In 2008, almost 96 percent of the water pumped from the Ogallala ...Contrasting management impacts in the Northern and Southern Ogallala. For the Northern Ogallala, sufficient precipitation helps prevent the depletion of the aquifer caused by water withdrawals. Without assimilating GRACE observations, the model tends to underestimate groundwater recharge. So, assimilation is essential to capture water storage ...The occasional detection of pesticides in deeper parts of the Ogallala Formation indicates that contamination pathways exist. Dissolved solids, which are a direct measure of salinity, had 29 ... Ogallala formation, Much of the Ogallala Formation was eroded away and stream channels became established. Sketch courtesy of Wyoming Geological Survey. Today, the Laramie Range , a northern extension of the Colorado Front Range, extends from the Colorado—Wyoming state line north and west to near Casper, Wyoming., The Ogallala Formation, Pleistocene deposits, and alluvium combine to form the High Plains aquifer. Water Resources in the High Plains Aquifer. Usable water in the High Plains aquifer is in the pore spaces between particles of sand and gravel. This water (called groundwater) accumulated slowly--in some of the deeper parts of the aquifer, over ..., Ogallala Formation..-----_ 29. CONTRIBUTIONS TO THE HYDROLOGY OF THE UNITED STATES GEOLOGY AND GROUND-WATER RESOURCES IN EASTERN CHEYENNE AND KIOWA COUNTIES, COLORADO By AjjNOii) 3. BOETTCHEE ABSTRACT The principal source of ground water in eastern Cheyenne and Kiowa Coun­ ties, Colo., is the Ogallala Formation of Pliocene age. ..., Opalized fossil bones and shells of diatoms are found in the Ogallala Formation, as is a green opal that acts as a cement in hard, erosion-resistant sandstones. Chemical …, But farmers are pulling water out of the Ogallala faster than rain and snow can recharge it. Between 1900 and 2008 they drained some 89 trillion gallons from the aquifer - equivalent to two ..., The principal water-yielding geologic unit of the aquifer is the Ogallala Formation of Miocene age, a heterogeneous mixture of clay, silt, sand, and gravel that was deposited by a network of braided streams which flowed eastward from the ancestral Rocky Mountains. Because it consists largely of the Ogallala Formation, the High Plains aquifer ..., Apr 20, 2021 · In general, the Trinity and Fredericksburg Groups and Ogallala Formation exhibit a slight regional dip (dip angle of about 0.14 degrees) to the southeast with dip directions becoming more to the south with each successively overlying unit (105, 110, and 125 degrees for the bases of the Trinity and Fredericksburg Groups and Ogallala Formation ... , Ogallala Formation (Pliocene) at surface, covers 6 % of this area. CIMARRON- Generally semiconsolidated clay, silt, sand, gravel, and caliche 0 to 400 feet thick. BEAVER- Interbedded sand, siltstone, clay, gravel lenses, and thin limestone. Caliche common near surface but occurrence is not limited to the surface., Ogallala Formation. CIMARRON- Generally semiconsolidated clay, silt, sand, gravel, and caliche 0 to 400 feet thick. BEAVER- Interbedded sand, siltstone, clay, gravel lenses, and thin limestone. Caliche common near surface but occurrence is not limited to the surface. Caliche accounts for most of the white color in the Ogallala. , Most of the area of the Pierre is covered by the younger Ogallala Formation. Several outliers both on the surface and in the subsurface are present east of the eastern margin of the formation. These are located in Phillips, Norton (Frye and Leonard, 1949), Graham, Gove, and Logan Counties. Remnants in Gove and Logan Counties are preserved in ..., The Ogallala Aquifer is the largest aquifer in the United States and is a major aquifer of Texas underlying much of the High Plains region. The aquifer consists of sand, gravel, clay, and silt and has a maximum thickness of 800 feet. Freshwater saturated thickness averages 95 feet. Water to the north of the Canadian River is generally fresh ..., Site identification number Each site in the USGS data base has a unique 8- to 15-digit identification number. 341501103500201. n/a. Site name This is the official name of the site in the database. For well information this can be a district-assigned local number. Mesa- Ogallala Formation, lower unit, sand layer. n/a., this region, the Ogallala crops out in steep escarpments alongtheeasternedgeof theHigh Plains. Two hydrodynamically and physio-graphicallydistinctregions — theNorthernandthe Southern High Plains — are separated by the Canadian River Valley.In the study area, the Ogallala Formation coversapproximately111,000 km 2(45,000mi2);90,000km2(36 ..., The Ogallala Aquifer is the largest aquifer in the United States and is a major aquifer of Texas underlying much of the High Plains region. The aquifer consists of sand, gravel, clay, and silt and has a maximum thickness of 800 feet. Freshwater saturated thickness averages 95 feet. Water to the north of the Canadian River is generally fresh ..., In 2001, Kansas formed a special citizens' committee to advise the governor and legislature on potential groundwater conservation policies (Ogallala Aquifer ..., The North Park Formation is a geologic formation in Colorado. It preserves fossils dating back to the Neogene period. See also. Earth sciences portal; Paleontology portal; List of fossiliferous stratigraphic units in Colorado; Paleontology in Colorado; References. Various Contributors to the Paleobiology Database., Although some slight eastward overlap may exist near the eastern margin of the formation, the Ogallala is in the main composed of a series of valley fillings, …, In turn, the Ogallala Formation was subdivided into a lower unnamed member and an upper member, the Rexroad. In Ford County, Waite (1942) assigned all the Tertiary deposits to the middle and upper Pliocene Ogallala Formation. The Ogallala was further subdivided into two members following Frye (1942). In Finney and Gray counties, Latta (1944 ..., The Neogene Ogallala Formation underlies much of the North American High Plains region and is composed chieflyoffluvial and eolian sediments consisting of interbedded conglomerate, sandstone,, base of the Ogallala Formation to the potentiometric surface. The saturated thickness in Oklahoma ranges from more than 400 feet to less than 50 feet. Natural recharge to the aquifer from precipitation occurs throughout the area but is extremely variable. Dryland agricultural practices appear to enhance, The Ogallala Formation is the principal geologic unit in the High Plains aquifer in eastern Colorado and New Mexico. The Ogallala generally consists of an unconsolidated and poorly sorted sequence of gravel, sand, silt, and clay. Moderately to well-cemented zones within the Ogallala are resistant to weathering and form ledges in outcrop areas., The Ogallala Formation has a thickness from 0 to approximately 800 feet, with an average saturated thickness of 95 feet . Throughout most of the Ogallala Aquifer area, withdrawal of water has exceeded the recharge rate. Water levels have declined in excess of 300 feet in the last 50 to 60 years. The use of groundwater from the Ogallala is ..., Opalized fossil bones and shells of diatoms are found in the Ogallala Formation, as is a green opal that acts as a cement in hard, erosion-resistant sandstones. Chemical …, The Ogallala Formation ranges in thickness from a few meters to more than 90 m. The formation was deposited on an erosional surface exposing rocks of Cretaceous age and was itself eroded after deposition, partially accounting for the changes in thickness., Most of the Ogallala sits in these clay formation areas. In fact, the aquifer is almost stagnant. Water from one zone doesn't move to another zone. ... "The Ogallala is a mined aquifer, different areas have different capacities and life spans," Woomer said. "Our area is drawing water at a higher rate than it is recharging. It's not ..., Ogallala Formation (Pliocene) at surface, covers 61 % of this area. ... Includes Ogallala and Laverne Formations of Pliocene age and younger deposits of Pleistocene age. Locally the units are tightly cemented by calcium carbonate; other places, they are very poorly consolidated and nearly free of cementing materials. Thickness ranges from 0 to ..., The Ogallala formation consists of fluviatile, late Tertiary (Neogene) deposits that underlie the surface that forms the High Plains. Ranging up to 300 feet in thickness, these deposits extend from Texas to South Dakota in a broad belt several hundred miles wide. Contrary to prevalent concepts, the Ogallala was not deposited as a series of ..., The Ogallala Formation was named by Darton in 1899 from outcrops in Keith County, Nebraska. These beds had previously been referred to as part of the Loup Fork Formation, now an obsolete term. Darton considered the Ogallala to be equivalent, at least in part, to the "mortar beds," "tertiary grit," and "magnesia beds" of Kansas. , the Ogallala formation varies in about the same proportion as the volume of water in storage. Nebraska with 64,400 square miles and Texas with 36,080 are the largest. New Mexico, Oklahoma, South Dakota, and Wyoming all have less than 10,000 square miles of surface area underlain by the Ogallala.7 Table 1: Characteristics of the High Plains Aquifer., Ogallala Group or Formation (Miocene) at surface, covers < 0.1 % of this area. Silt, sand, sandstone, gravel and conglomerate. Predominantly interfingered fine- to coarse grained, poorly sorted, arkosic, fluvial deposits of light-gray, light-olive-gray, and grayish-green calcareous silt and sand, and locally poorly consolidated conglomerate ..., The formation of the Ogallala Aquifer started 24 million years ago, and ended 1.8 million years ago, according to an MIT Mission 2012 Clean Water report. This happened as sand and gravel that had eroded from the Rocky Mountains were carried eastwards by large rivers, and these sediments ended up covering the Great Plains landscape., From Wikipedia, the free encyclopedia. Ogallala may refer to: Ogallala, Nebraska. Ogallala Aquifer. Ogallala Commons. Ogallala Formation. Oglala Lakota (Sioux) This …, As this graph shows, depth to groundwater had a large range, varying from 33 to 379 feet. Most of the audited sites were extracting water from either the Rush Spring or Ogallala aquifers. The average groundwater depth was 104 feet for the wells tapping the Rush Spring and 273 feet for the Ogallala aquifers. Figure 5.