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Donald G. Jorgensen

Publications and source records attributed to Donald G. Jorgensen.

15 recordsLinked to original sources

Accounting for intracell flow in models with emphasis on water table recharge and stream-aquifer interaction: 2. A procedure

Intercepted intracell flow, especially if cell includes water table recharge and a stream ((sink), can result in significant model error if not accounted for. A procedure utilizing net flow per cell ( F n ) that accounts for intercepted intracell flow can be used for both steady state and transient simulations. Germane to the procedure is the determination of the ratio of area of influence of the interior sink to the area of the cell ( A i / A c ). A i is the area in which water table recharge has the potential to be intercepted by the sink. Determining A i / A c requires either a detailed water table map or observation of stream conditions within the cell. A proportioning parameter M , which is equal to 1 or slightly less and is a function of cell geometry, is used to determine how much of the water that has potential for interception is intercepted by the sink within the cell. Also germane to the procedure is the determination of the flow across the streambed ( F s ), which is not directly a function of cell size, due to difference in head between the water level in the stream and the potentiometric surface of the aquifer underlying the streambed. The use of F n for steady state simulations allows simulation of water levels without utilizing head-dependent or constant head boundary conditions which tend to constrain the model-calculated water levels, an undesirable result if a comparison of measured and calculated water levels is being made. Transient simulations of streams usually utilize a head-dependent boundary condition and a leakance value to model a stream. Leakance values for each model cell can be determined from a steady state simulation, which used the net flow per cell procedure. For transient simulation, F n would not include F s . Also, for transient simulation it is necessary to check F n at different time intervals because M and A i / A c are not constant and change with time. The procedure was used successfully in two different models of the aquifer system in the Ozarks. The use of F n was essential to the two model studies because most model cells in both models contained water table recharge and multiple sinks.

Water Resources Research

Field use of orifice meters

A well-designed and calibrated orifice meter is an accurate and inexpensive measuring device for flow. Endline orifices can be calibrated at work sites by solving an equation that interrelates easily measured dimensions of the orifice and outflow.

Groundwater

Analysis of regional aquifers in the central Midwest of the United States in Kansas, Nebraska, and parts of Arkansas, Colorado, Missouri, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming: Summary

Large quantities of ground water are available for use from three regional aquifer systems in the central Midwest of the United States. Parts of the lowermost aquifer contain nearly immobile brine and may be hydrologically suitable for material storage or waste disposal. Results of numerical modeling and geochemical analyses confirm general concepts of ground-water flow in the regional aquifer systems.

Arkansas, Colorado, Kansas, Missouri, Nebraska, Ne

Regional aquifers in Kansas, Nebraska, and parts of Arkansas, Colorado, Missouri, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming: Geohydrologic framework

Regional aquifers are described within a 370,000-square-mile area extending from the foothills of the Rocky Mountains in Colorado to the Missouri and Mississippi Rivers in eastern Nebraska and Missouri, and from South Dakota to the Ouachita, Arbuckle, and Wichita Mountains of Arkansas and Oklahoma. The present geohydrologic framework of aquifers and confining units in this area is controlled by topography, geologic structures, and hydraulic properties. All of these characteristics are the result of past geologic and hydrologic processes. From the end of the Precambrian to Late Cambrian time, the area was above sea level, and an uneven erosional surface had developed on the fractured crystalline rocks. From Late Cambrian through Middle Ordovician time, a transgressive but cyclic sea covered the area. The oldest deposits were mostly permeable sand followed by slightly permeable calcareous mud consisting of aragonite and algal remains.

Arkansas, Colorado, Kansas, Missouri, Nebraska, Ne

Paleohydrology of the Anadarko Basin, central United States

Geohydrologic systems in the Anadarko basin in the central United States are controlled by topography, climate, geologic structures, and aquifer hydraulic properties, all of which are the result of past geologic and hydrologic processes, including tectonics and diagenesis. From Late Cambrian through Middle Ordovician time, a generally transgressive but cyclic sea covered the area. The first deposits were permPable sand, followed by calcareous mud. During periods of sea transgression, burial diagenesis decreased porosity and permeability. During periods of sea recession, uplift diagenesis increased porosity and permeability, especially in exposed rocks. During most of Silurian and Devonian time, the sea receded; increased porosity and permeability resulted from uplift diagenesis. However, at the end of the Devonian and during the Early Mississippian, very slightly permeable clay, which now is a regional confining unit, was deposited in a mostly euxinic sea. Later during Mississippian time, calcareous muds, which became limestone, were deposited in and adjacent to the Anadarko basin and underwent burial diagenesis. During Pennsylvanian time, rapid sedimentation accompanied rapid subsidence in the Anadarko basin. A geopressure zone probably resulted when sediments with little permeability trapped depositional water in Lower Pennsylvanian sands. Burial diagenesis included compaction and thermal alteration of deeply buried organic material, which released carbon dioxide, water, and hydrocarbons. By Middle Pennsylvanian time, the sea had submerged most of the central United States, including the Ozarks, as tectonic activity reached its maximum. During Late Pennsylvanian and Early Permian time, the Ouachita uplift had been formed and was higher than the Ozarks. Uplift was accompanied by a regional upward tilt toward the Ouachita-Ozarks area; the sea receded westward, depositing large quantities of calcareous mud and clay, and precipitating evaporitic material in the restricted-circulation environment. By the end of Permian time, > 20,000 ft of Pennsylvanian and Permian sediments had been deposited in the Anadarko basin. These thick sediments caused rapid and extreme burial diagenesis, including alteration of organic material. During Permian time in the Ozarks area, development of the Ozark Plateaus aquifer system commenced in the permeable Cambrian-Mississippian rocks near the St. Francois Mountains as the Pennsylvanian confining material was removed. Since Permian time, uplift diagenesis has been more active than burial diagenesis in the Anadarko basin. Synopsis of paleohydrologic interpretation indicates that Cambrian-Mississippian rocks in the Anadarko basin should be relatively impermeable, except for local secondary permeability, because rocks in the basin have undergone little uplift diagenesis.

Book chapter

Hydrology and model of North Fork Solomon River Valley, Kirwin Dam to Waconda Lake, north-central Kansas

The alluvial valley of the North Fork Solomon River is an important agricultural area. Reservoir releases diverted below Kirwin Dam are the principal source of irrigation water. During the 1970'S, severe water shortages occurred in Kirwin Reservoir and other nearby reservoirs as a result of an extended drought. Some evidence indicates that surface-water shortages may have been the result of a change in the rainfall-runoff relationship. Examination of the rainfall-runoff relationship shows no apparent trend from 1951 to 1968, but annual records from 1969 to 1976 indicate that deficient rainfall occurred during 6 of the 8 years. Ground water from the alluvial aquifer underlying the river valley also is used extensively for irrigation. Utilization of ground water for irrigation greatly increased from about 200 acre-feet in 1955 to about 12,300 acre-feet in 1976. Part of the surface water diverted for irrigation has percolated downward into the aquifer raising the ground-water level. Ground-water storage in the aquifer increased from 230,000 acre-feet in 1946 to 275,000 acre-feet in 1976-77. A digital model was used to simulate the steady-state conditions in the aquifer prior to closure of Kirwin Dam. Model results indicated that precipitation was the major source of recharge to the aquifer. The effective recharge, or gain from precipitation minus evapotranspiration, was about 11,700 acre-feet per year. The major element of discharge from the aquifer was leakage to the river. The simulated net leakage (leakage to the river minus leakage from the river) was about 11,500 acre-feet per year. The simulated value is consistent with the estimated gain in base flow of the river within the area modeled. Measurements of seepage used to determine gain and loss to the stream were made twice during 1976. Based on these measurements and on base-flow periods identified from hydrographs, it was estimated that the ground-water discharge to the stream has increased about 4,000 acre-feet per year from 1946 to 1976. During the same period, ground water withdrawn from the aquifer increased 12,100 acre-feet per year. Hydrographs of water levels in wells indicate some withdrawal from aquifer storage during 1976, possibly as a combined result of below-normal rainfall and greatly increased pumpage. The analysis of data is inconclusive as to whether the aquifer can sustain increased groundwater development. However, the analysis does indicate that the aquifer could sustain withdrawals at the 1976 rate for several consecutive years of drought similar to the 1976 conditions.

Kansas

Relationships between basic soils-engineering equations and basic ground-water flow equations

The many varied though related terms developed by ground-water hydrologists and by soils engineers are useful to each discipline, but their differences in terminology hinder the use of related information in interdisciplinary studies. Equations for the Terzaghi theory of consolidation and equations for ground-water flow are identical under specific conditions. A combination of the two sets of equations relates porosity to void ratio and relates the modulus of elasticity to the coefficient of compressibility, coefficient of volume compressibility, compression index, coefficient of consolidation, specific storage, and ultimate compaction. Also, transient ground-water flow is related to coefficient of consolidation, rate of soil compaction, and hydraulic conductivity. Examples show that soils-engineering data and concepts are useful to solution of problems in ground-water hydrology.

Water Supply Paper

Salt-water encroachment in aquifers near the Houston Ship Channel, Texas

Interpretations based on analyses of inorganic constituents, dissolved organic carbon, and tritium in ground water and surface waters indicate that the Houston Ship Channel is the source of salt water that has been detected in shallow wells between Baytown and Houston, Texas. Analyses of the ratios of the stable isotopes of carbon, sulfur, hydrogen, and oxygen were inconclusive as to the source of the salt water, but were consistent with the hypothesis that the ship channel is the source. Estimates of the amount of vertical leakage indicate that the quantity of salt water encroaching from the surface or near surface to the Chicot aquifer, including leakage from the Houston Ship Channel, is not sufficient to appreciably alter the inorganic chemical quality of the ground water in any large segment of the aquifer. The effects of other contaminants, particularly organic substances, are not known. (Woodard-USGS)

Open-File Report

Water resources of the Big Sioux River Valley near Sioux Falls, South Dakota

The major sources of water in the Big Sioux River valley between Sioux Falls and Dell Rapids, S.Dak., are the Big Sioux River and the glacial outwash aquifer beneath the flood plain. The river and the aquifer are hydraulically connected. The Big Sioux River has an average annual discharge of 246 cubic feet per second, on the average exceeds bankfull stage every 2.3 years, and has moderate basin storage.. Periods of low flow are common in the late summer, fall, and winter. A low flow of 0.1 cubic foot per second has been recorded. The outwash aquifer is composed of permeable sand, sand and gravel, and some boulders. The aquifer underlies an area of 33 square miles and commonly has a saturated thickness of less than 30 feet. Aquifer tests and measurements of streamflow indicate a rate of streambed infiltration of about 6 gallons per day per square foot. Analyses of streambed samples and interpretations of lithology from an electric log indicate that the streambed sediments in the diversion channel of the Big Sioux River consist largely of relatively impermeable silts and clays. Under normal climatic conditions, most of the water pumped by the city of Sioux Falls is water that entered the aquifer by streambed infiltration. To evaluate the importance of the aquifer in the hydrologic system, both an electrical analog model and a digital model were programmed for storage depletion alone. These models were used to determine the water-level declines in the aquifer that would result from 1 year of withdrawal at a rate of 9-10 million gallons per day. Both models indicated that the existing well field can yield water at that rate for more than 1 year. The analog model was also used to determine the maximum average daily yield of the aquifer-river system for a 2-year period modeled for the minimum recorded stream discharge and for streambed infiltration as the only recharge. The maximum average yield under these conditions would be less than 24 million gallons per day. Most of the water pumped during this period would be from aquifer storage. Water from the river is generally less mineralized, softer, and easier to treat than ground water. Water pumped from wells near the river is similar in quality to the river water, but does not have the objectionable odors or tastes often present in water from the river.

South Dakota