Now showing items 7066-7085 of 14895

    • A hydrogeochemical evaluation of the lower Cienega Creek sub-basin, Pima County, Arizona

      Conklin, Martha H.; Grahn, Howard Lance; Conklin, Martha H.; Bassett, R. L. (The University of Arizona., 1995)
      Mass transport modeling of ground and surface waters upstream of perennial Cienega Creek, Arizona, delineate processes which control ground water chemistry in this arid alluvial basin. NETPATH modeling shows that the aquifer is open to CO2 flux, and that dissolution of gypsum, redistribution of carbonate minerals, and cation exchange of Ca2+ for Na+, control the evolution of ground and surface water chemistry. Calcium bicarbonate waters which recharge the basin margin, evolve to calcium-sulfate waters during passage through the alluvial aquifer, and produce a quantifiable chemical evolution of ground water within the aquifer. Evaluation of a 10-year data base, plus the clarification of controlling chemical processes, allow a reinterpretation of the source of Cienega Creek waters, which is shown in this study to be the upstream alluvial basin. These findings are partially corroborated by an associated geophysical study which confirms a basin flow pattern parallel to the flow path assumed by this investigation.
    • Hydrogeochemical Modeling of Western Mountain Front Recharge, Upper Cienega Creek Sub-Basin, Pima County, Arizona

      Conklin, Martha; Huth, Hans Jarlath (The University of Arizona., 1997)
      Using historical and current water quality data, the geochemical processes responsible for controlling the chemical evolution of groundwater in the Upper Cienega Creek Basin are characterized and modeled. Spatially, waters evolve from a calcium-bicarbonate type at the mountain front to a sodium-bicarbonate type in the central basin. Analyses for Cienega Creek perennial flows demonstrate a relatively high sodium concentration (greater than 1.71 mmol/l) characteristic of central basin groundwaters. Given the similar high sodium signature, it is assumed that surface and groundwaters evolve under the same geochemical controls while originating from the same mountain-front recharge sources. Mass balance modeling demonstrates that the chemical processes controlling water quality in the Upper Cienega Creek Basin are typical of alluvial basins in the Southwest (Robertson, 1991).
    • The hydrogeochemistry of strontium in the Ranegras Plain groundwater basin

      Dolegowski, John Richard,1951-; Simpson, Eugene S.; Davis, Stan N.; Long, Austin (The University of Arizona., 1988)
      The occurrence, sources, and governing geochemical reactions of strontium in the groundwater of the Ranegras Plain basin, western Arizona, were evaluated by the analysis of basin geology, groundwater quality data, and chemical analyses of basin drill cuttings and potential strontium source rocks from the surrounding mountains. Four potential mechanisms controlling the hydrogeochemistry of strontium were evaluated: (1) celestite and strontianite dissolution; (2) strontium release during the weathering of silicate minerals; (3) the solid solution of strontium in calcite, aragonite, and gypsum; and (4) cation exchange. Evaporite dissolution, aluminosilicate mineral hydrolysis, calcite precipitation, and cation exchange control the basin hydrogeochemistry. Strontium concentrations in groundwater range from 0.060 to 4.4 milligrams per liter and are controlled primarily by pH, gypsum dissolution and calcite precipitation of which strontium is a trace component, and the cation exchange of strontium on aquifer minerals.
    • Hydrogeologic evaluation of the Sonoita Creek aquifer

      Bradbeer, Gayle Elizabeth,1953-; Evans, Daniel D. (The University of Arizona., 1978)
      This study examines the potential of the area along Sonoita Creek upstream from Rio Rico, Arizona, 8-1/2 miles to Lake Patagonia dam, for water production from the shallow alluvial Sonoita Creek aquifer using geologic and hydrologic surveys made in 1977. The aquifer was divided into two geographical regions. Sources of recharge to and discharge from each region were examined and a quantitative water budget was made for each region. The three potential sources of water, the extractable stored volume, the rejected recharge, and the natural discharge were quantified, and the feasibility of exploiting each was discussed, for an emergency supply and for a sustained yield production.
    • Hydrogeologic field study of the Koongarra Uranium Deposit in the Northern Territory of Australia

      Marley, Robert Douglas,1962-; Davis, Stanley N. (The University of Arizona., 1990)
      Water level, aquifer test, and slug-test data indicate that the Koongarra uranium deposit is within a low permeability, semi-confined, fractured-schist aquifer. Water levels demonstrate semi-diurnal and diurnal fluctuations related to earth tides and evapotranspiration stresses. Hydraulic test data were analyzed with homogenous isotropic and homogenous anisotropic models which allowed parameter estimation for sub-regions of the study area. Dominant anisotropy is subparallel to lithologic layering and the reverse fault. Slug tests reveal regions controlled by low storage but highly conductive fractures and isolated regions of low conductivity. Hydraulic connection of the weathered zone with the underlying schist is dependent on clay content and fractures. Environmental isotopes indicate ground water has been isolated from the atmosphere for at least 40 years and possibly several thousand years in some locations. Water budget calculations indicate the majority of recharge must be from direct infiltration through the weathered profile to account for the calculated ground-water fluxes.
    • Hydrogeologic investigations for a groundwater contamination site Phoenix, Arizona

      Hall, Dennis Gregory, 1954- (The University of Arizona., 1991)
    • A hydrogeologic resource assessment of the lower Babocomari Watershed, Arizona

      Schwartzman, Peter N.,1961- (The University of Arizona., 1990)
      Perennial streamflow and a rich riparian habitat along portions of the Babocomari River is supported by the regional ground-water system. A hydrologic resource assessment of the lower Babocomari Watershed (upper San Pedro Basin, Arizona) was performed to characterize the system which supports the current flow regime of the river, and estimate the effects of future pumping on hydrologic conditions along the river. Descriptions of the physiography, climate, vegetation, and geology of the study area were primarily derived from literature review. Descriptions of the ground-water system, surface-water system, surface-water/ground-water interaction, riparian vegetation, and water quality were chiefly derived from field work and laboratory analysis. Descriptions were substantiated with flow-net, water-budget, and aquifer-test analyses. Current and predicted future rates of pumping were quantified, and were used to make preliminary analytical estimations of drawdown effects on hydrologic conditions along the Babocomari River.
    • Hydrogeological analysis of groundwater flow in Sonoita Creek basin, Santa Cruz County, Arizona

      Nassereddin, Muhamad Taher,1933-; Harshbarger, J. W.; Pye, W. D.; Wright, J. J. (The University of Arizona., 1967)
      The Sonoita Creek basin lies in a north trending intermontane valley in southeastern Arizona. Mature dissected mountains rise abruptly from long alluvial slopes and culminate in peaks ranging from 1000 to 1300 feet above the valley floor. The mountains surrounding the alluvial sediments are of volcanic rocks of Miocene ? age, and have been subjected to tectonic disturbance which resulted in extensive faulting, folding, and the formation of joint systems. The alluvial sediments have been divided into five units based on their stratigraphic position, structural involvement, lithology, and permeability. The oldest unit in the basin is unit No. 5 and the youngest is unit No. 1. Groundwater supplies of the Sonoita Creek basin are developed largely from alluvial unit No. 4, and minor supplies from alluvial unit No. 1. The groundwater originates as precipitation on the mountain areas and on the floor of the valley. The average rainfall on the valley floor is about 20 inches per year while on the mountains it is more than 50 inches per year. A minor part of the groundwater recharge is from the discharge of Monkey spring into the northern part of the basin. Groundwater is discharged from the Sonoita Creek basin through evaporation, as effluent flow of about 7 cubic feet per second through Sonoita Creek, and by artificial discharge through pumping. The perennial streamflow in Sonoita Creek near Patagonia is due to the impervious volcanic rocks in the subsurface, which crop out 500 feet south of the town, forcing the groundwater to discharge at the surface. Groundwater in the basin is generally of excellent to good quality for irrigation use, and medium to good for domestic purposes. The groundwater contains high percentages of sulphate, calcium, and bicarbonates.
    • A hydrogeological evaluation and feasibility analysis of artificial groundwater recharge and recovery in eastern Pauba Valley, Riverside County, California

      Neuman, Shlomo P.; Phraner, Ralph Wilson, 1950- (The University of Arizona., 1991)
      The Rancho California Water District has an opportunity to conjunctively manage available ground, surface, imported, and reclaimed water resources through a program of artificial recharge and recovery. The site of proposed operations is eastern Pauba Valley, Riverside County, California. Hydrogeological analyses were conducted to identify valley aquifers, evaluate hydraulic properties and quantify ground water storage, movement and yield. Field studies included nine aquifer tests, a survey of well locations and construction of five monitoring wells. All data collected were entered into a computerized Water Resources Information Management System (WRIMS) custom configured for the project. A finite-difference computer simulation model was constructed to evaluate the feasibility and facilities requirements of two alternative recharge and recovery programs. Computer simulation results confirm the feasibility of 9,000 and 18,000 acre feet per year recharge and recovery programs.
    • Hydrogeological study and evaluation of water resources of the Collo Basin, Skikda, Algeria

      Beloulou, Laroussi,1959-; Buras, Nathan; Evans, Daniel D.; Davis, Donald R. (The University of Arizona., 1987)
      The Collo Basin, a small coastal aquifer, consists of three different alluvial units characterized by different hydraulic properties. If adequately managed, alluvial unit No. 3, being the best aquifer, is capable to supply domestic water for the city of Collo in the short and the long run as well. The estimated rate of water withdrawal from unit No. 3 exceeds more or less that of direct recharge by precipitation, causing hence a lowering of the water table. Consequently, recent chemical analyses of water samples show that groundwater is, to some extent, further contaminated by sea water. Therfore, it is time for local authorities to take some legal measures prohibiting any additional well drillings in this area as to prevent a possible disaster until all hydrological parameters are identified with certain degree of accuracy.
    • Hydrogeology and a quantitative model to predict a safe yield for the area of Villa Juarez, Durango, Mexico

      Flores Castro, Sergio Alejandro,1951-; Ince, Simon; Guertin, D. Phillip; Fogel, Martin M. (The University of Arizona., 1987)
      The Villa Juarez, Durango, area was selected as the appropriate location for constructing an electrical generating plant. Although it has been determined that the water supply is adequate for the present time, it is necessary to determine whether this supply will be adequate for operation of the electrical plant during a period of 20 years. A groundwater model was used to predict the safe yield in the study area. The groundwater demand will be 300 L/s, plus that extracted from the unconfined aquifer in the Villa Juarez area. The total pumpage will be 151,454 m³/d in 1988. The predicted drop in water levels will be between 4 and 7 m, depending on the well location. In areas distant from the river the water level is predicted to drop about 13 m. Considering the available data, very good agreement was found between observed and simulated water levels during the calibration period, and the results of the prediction period are reliable.
    • The hydrogeology and development of the ground water resources in the El Asentamiento Campesino El Cortijo, Estado Aragua, Venezuela.

      Marquez Oropeza, Romulo,1938-; Wright, Jerome J.; Simpson, Eugene Sidney; Pye, Willard Dickison (The University of Arizona., 1970)
      This thesis pertains to the ground water resources of the E1 Asentamiento Campesino E1 Cortijo area, which is located within the mountain ranges of north-central Venezuela, South America. The area described in this thesis is an agricultural area of 400 hectares (1,000 acres) lying in a basin of 2,100 hectares (5,187 acres). The sediments underlying the area consist of about 100 meters (328 feet) of gravel, sand and clay of Quaternary age and are bounded on the north and south by relatively impermeable metamorphic rocks. The purpose of the investigation was to determine and to describe the ground water conditions in the mentioned area with special emphasis on the development of the ground water resources. The sources and movement of ground water, the recharge and discharge relations and the effects of pumping on the water levels are described. Ground water occurs under water table conditions and precipitation and unqerf10w represent the sources of recharge to the aquifer. The coefficients of transmissibility and storage were estimated to be 1,800 cubic meters per day (154,700 g./d./ft.), and 0.11 respectively. Water quality is satisfactory for irrigation use, but concentrations of turbidity, apparent color and dissolved-iron exceed the amount recommended by the United States Public Health Service for drinking purposes.
    • Hydrogeology and groundwater development in a salar basin in the Andes Mountains of northern Chile

      Harshbarger, John W.; Montgomery, Errol L.; Victor, William Ray,1953-; Simpson, Eugene S.; Simpson, Eugene S.; Evans, Daniel D. (The University of Arizona., 1986)
      A closed salar basin, 4,100 to more than 5,350 meters above mean sea level, is a potential source of fresh groundwater for proposed mining operations in the arid Andes Mountains of northern Chile. The prolific basin aquifer, comprised of alluvial deposits underlain by fractured ignimbrite, occurs over an area of 23 square kilometers. Transmissivity ranges from 20 to 7,100 square meters per day. Volume of potentially recoverable groundwater is equal to a constant yield of 200 liters per second for 30 years. Groundwater discharge occurs via evaporation at the salar, and is in approximate equilibrium with groundwater recharge. Projected long-term combined pumping rate from two proposed production wells is 164 liters per second. This pumping rate is in the same magnitude as evaporation at the salar. Proposed pumping would diminish surface water supplies in the basin, and would result in a new dynamic equilibrium for the groundwater system.
    • Hydrogeology and groundwater modeling study of the Azua Valley, Dominican Republic

      Pérez Pérez, Odalís, 1950- (The University of Arizona., 1989)
      The results of the model can be used for enhancing the integrated management of the water resources of the Azua Valley. The model shows the effects of an extensive drainage network on the high ground-water levels which prevailed from 1983 to 1988. A sensitivity analysis also shows the zones of the aquifer which require development of new pumpage in order to overcome the drainage problem in areas still flooded by uncontrolled artesian flow. The results of the model can be used for enhancing the integrated management of the water resources of the Azua Valley.
    • HYDROGEOLOGY AND PALEOHYDROGEOLOGY OF THE KOONGARRA NATURAL ANALOGUE, NORTHERN TERRITORY, AUSTRALIA

      Ekwurzel, Brenda; Braumiller, Sue; Ekwurzel, Brenda (The University of Arizona., 2004)
      The Koongarra site is one of the most extensively studied natural analogues in the world. Data for the Koongarra site are re-examined to develop a hydrogeological and paleohydrogeological conceptual model of the natural analogue as a basis for simulating the development of the dispersion fan. Geological, geophysical, hydrologic, and paleoclimatic data are interpreted to determine present-day conditions on the boundaries of host schist and the hydrogeological structure of the host formation. The configuration of groundwater flow through host schist is inferred from the structure of the formation and boundary conditions. Groundwater level measurements and data describing the di stribution of aqueous uranium and other aqueous species and parameters are consistent with the proposed hydrogeological model. Information about the geochronology of the site and paleoclimate of the region are considered to show that sources of recharge to host schist, factors determining the hydrogeological structure of the host formation , and the configuration of groundwater flow through the site are essentially unchanged for the last two million years or more. The proposed flow field descended through the No. 1 orebody with the erosion (lowering) of the land surface and advance of the weathered profile to form the Koongarra dispersion fan. Data describing the three-dimensional distribution of uranium minerals comprising the dispersion fan are consistent with the proposed paleohydrogeological model. Paleoclimatic records and an estimate of the present rate of advance of the weathering front are used to approximate the age and rate of development of the fan, initiated two million years ago.
    • Hydrogeology and simulation of ground-water and surface-water flow in Pinal Creek Basin, Gila County, Arizona

      Neaville, Chris C. (The University of Arizona., 1991)
      Acidic water with elevated concentrations of metals has contaminated a stream and alluvial aquifer in a mining district near Globe, Arizona. The contaminated aquifer is a narrow layer of unconsolidated alluvium along Miami Wash and Final Creek. The purpose of this study was to evaluate the hydrogeology of this area and to simulate the surface- and ground-water flow. The alluvium overlies basin fill which extends throughout most of Final Creek basin. Together, the alluvium and basin fill comprise the primary aquifer in the basin. Horizontal hydraulic conductivities have been estimated to be about 200 m/day in the alluvium, and average linear, ground-water flow velocities are on the order of 5 m/day. Flow was simulated by a three-dimensional, finite-difference, ground-water flow model that maintains a streamflow water budget. Steady-state simulations were performed and adjusted to represent average annual water budget conditions. The transient simulation period covers September 1984 to April 1989, for which considerable data were available for model calibration.
    • Hydrogeology and water resources of Middle Kirkland Creek basin, Yavapai county, Arizona.

      Randall, Jeffrey Hunt.; Harshbarger, John W.; Wilson, Gray; DeCook, Jim (The University of Arizona., 1974)
      Middle Kirkland Creek basin lies at the northern edge of the Basin and Range province 20 miles southwest of Prescott, Arizona. The hydrogeologic system of the basin includes two major aquifers: alluvial sediments and basaltic volcanics. The alluvial sediments are a series of granitic pebble conglomerates intercalated with basalt flows in some areas overlaid by finegrained lacustrine sediments that grade laterally into a pebble conglomerate. Overlying these units is a thin narrow deposit of unconsolidated sands, gravels, and silts representing the flood-plain alluvium of Kirkland Creek. The estimated transmissitivities of the alluvial sediments are as follows: Lower Kirkland Valley - 75,000 to 100,000 gpd/ft Thompsons Valley - 30,000 to 60 , 000 gpd/ft Well yields in Lower Kirkland Valley range from 500 to 1200 gpm and those from Thompsons Valley 200 to 500 gpm. The decreased yields in Thompsons Valley result from the finer texture of the flood-plain alluvium in this area. The basalt aquifer consists of a series of more than 1000 feet of fractured basalt flows interbedded with cinder and conglomeratic layers. The transmissivity of this unit is estimated to range from 50,000 to 200,000 gpd/ft. Wells drilled in this unit could yield 200 to 1000 gpm depending on the nature of the fracturing.
    • Hydrogeology of a contaminated industrial site on filled land

      Feldman, Peter Roy,1957-; Simpson, Eugene S.; Wilson; Yeh (The University of Arizona., 1989)
      A detailed hydrologic investigation was conducted at a wood preservative treatment plant to determine the extent of soil and groundwater contamination and to define the rate at which preservative compounds (polycyclic aromatic hydrocarbons and phenols) are migrating to an adjacent saltwater body. Contamination appears restricted to the uppermost aquifer, which occurs in a sequence of fill deposits comprising the land surface at the site. Groundwater flow and contaminant distribution are likely controlled by heterogeneities within the fill deposits, which are a result of placement history and other factors such as buried shorelines, bulkheads, and filled channels. Calculations of total contaminant flux from the groundwater system to the adjacent saltwater body range from 143 to 191 pounds per year.
    • Hydrogeology of a portion of the Santa Catalina Mountains.

      Belan, Rick Allen,1947-; Matlock, William G. (The University of Arizona., 1972)
      The hydrogeology of a portion of the Santa Catalina Mountains just north of Tucson, Arizona was studied. Groundwater level contour maps for 1930 and 1972 were made by establishing a well net, use of well logs and field observations. Water levels were measured in March, 1972. Water level records and well logs provided water level information for 1930. The resulting maps showed hydraulic gradients ranging from 400 feet per mile to 60 feet per mile, and seven possible groundwater recharge channels to the Tucson Basin aquifer. Comparing the 1930 and 1972 water level maps showed that the greatest water level change of about 60 feet has occurred along Rillito Creek because of heavier aquifer development. Less change in water levels has occurred in the foothills. Chemical quality analysis and temperature measurements were used to further define three local aquifers. Groundwater was generally of good quality, except in one mine well that had high salt concentrations because of ore deposits. A flow net analysis was used to estimate recharge moving to the lower lying Tucson Basin. Recharge of 382 acre feet per year was obtained, which represents about 50 acre feet per mile of mountain front per year.
    • Hydrogeology of Butler Valley, Arizona : an artificial recharge and ground-water storage prefeasibility study

      Herndon, Roy Lee.; Wilson, L. G.; Simpson, E. S. (The University of Arizona., 1985)
      A USGS finite-difference computer program was used to assess possible artificial recharge and recovery scenarios as part of a technical prefeasibility study of Butler Valley, Arizona. Available hydrogeologic data were compiled and analyzed to build a numerical groundwater flow model of the valley. Input data for the model were gathered from previous work as well as from field studies, including seismic refraction and gravity surveys and aquifer-pump tests performed as part of this investigation. The results of the computer simulations indicate that aquifer storage capacity increases in the upper portion of the basin due to a confined system in the lower portion. The computer model and available geologic data were used to identify potential locations in Butler Valley for artificial recharge operations. The areas along Cunningham Wash and the basin margins appear to be the most favorable for surficial water spreading. Artificial recharge using injection wells, though expensive, appears to be feasible from a hydrogeological standpoint, but chemical interactions between recharge water and native ground water could create undesireable well-screen clogging. Gravity and seismic refraction data collected at the outlet of Butler Valley indicate that ground-water outflow during recharge operations would be minimal because of a shallow subsurface bedrock aquiclude.