ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03196.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTDrill‐stem tests may be useful for such hydrogeological purposes as regional ground‐water or geothermal resource studies. Water samples, hydraulic head and hydraulic conductivity may be obtained from these tests.Analysis of 41 drill‐stem tests conducted for a regional ground‐water study reveals that maximum pressures recorded during a test should exceed 30 percent of the full scale of the pressure gauge used in the case of bourdon‐type instruments. Use of drill‐stem‐test data without consideration for percent deflection of the pressure recorder, even with evaluation of mechanical quality will mean that individual values of pressure head may be as much as 30 percent different from that which would be obtained in an observation well. The error is random and has a median value approximating that which would be observed in a well completed over the same interval. Use of large numbers of drill‐stem tests will produce hydraulic head maps which agree with those produced by conventional ob

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03197.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTThis paper presents ten theses summarizing: The cyclic pattern of precipitation and runoff in the Central Valley of California and the need for cyclic storage to insure regularity and continuity in water supply; the inadequacy of surface‐water storage because of evaporation losses and probable interference with ground‐water recharge; the blasted hopes of Federal and State water agencies for control and management of the ground‐water reservoir, because of potential conflict with private property rights; the artificial recharge by private and local enterprise; increasing emphasis in Federal and State programs upon surface reservoirs at increasing cost in money and water; the tendency of Federal policy to focus on the needs and clamors for irrigation water, with subsidies; and the availability of water from Federal projects now under construction for artificial recharge and subsurface storage, a first step to a long‐range program of cyclic

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03198.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTA mathematical model for estimating daily water levels from less than daily observations was used to analyze an existing water‐level observation network on Cape Cod, Massachusetts. The model assumes that the water‐level fluctuation curve can be approximated by a simple harmonic function of the form: wl(x)=M+A cos(2π/T×+ C) + Bx where wl(x) is the water level for day number x. M, A, C and B are constants, and T is the harmonic period.The analysis indicated that for those sites which are not affected by tidal fluctuations or man‐made influences (such as pumping), six water‐level measurements per year would allow daily water levels to be interpolated with a standard error of estimate of about 0.

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03199.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTSulfate sorption data determined from laboratory investigations were used to predict movement of sulfate during a field experiment of artificial ground‐water recharge in a basin near Lubbock, Texas. Laboratory studies confirmed that sulfate sorption is controlled in the system by surface area, content of iron oxides and hydroxides, and pH. Predicted sulfate distribution in the unsaturated zone was made by assuming constant one‐dimensional flow. Where these assumptions were met, predictions were generally good at shallow depths and for short times.At greater depths and longer times, these assumptions combined with other factors, such as changes in effective porosity, variable mineralogy, changing hydrodynamic dispersion coefficients, and variable infiltration rates contributed to the failure of the predicted values to match the observed data.It appears that sulfate distribution in the unsaturated zone during artificial recharge can be predicted by using easily derived laboratory data if the flow conditions in the field can be described adequat

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03200.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTTemperature logs were used to study the movement of water injected into wells penetrating the Pliocene Ogallala Formation in the High Plains of Texas. Descriptions of the results of three recharge tests are necessary because the hydrologic response to recharge at each site was very different. The water used for artificial recharge of the aquifer was derived from playa lakes in which the diurnal fluctuation of temperature was as much as 17 ° Celsius. Daily thermal cycles that resulted from injection of this water were traced through the aquifer by use of a series of temperature logs made at frequent intervals in cased holes specially constructed for logging. The thermal pulses were detected by logging holes as far as 46 meters (150 ft) from the recharge well.In areas where this technique was used, the Ogallala Formation consists of thick sections of uniform medium‐grained sand that visually appear uniform and thus were thought to have uniform hydraulic conductivity. However, the results of temperature logging at each of the three sites clearly demonstrate that the hydraulic conductivity varies greatly through these seemingly uniform lithologic units. Thermal pulse velocities as high as 4.6 meters (15 ft) per hour were found in thin zones immediately adjacent to sand where velocities were a few feet per day. Tracing with temperature logs is potentially useful in locating zones of high intrinsic permeability and in detecting apparent changes in rate of flow as a function of ti

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03201.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

ABSTRACTHydraulic conductivity studies of a consolidated pozzolanic material indicate that heat‐shrinkable tubing can be utilized to encase cylinders for use in a permeameter. The materials required for encasement of a sample include: heat‐shrinkable tubing, hose clamps, polyvinyl chloride discs, glass tubing, and an electric oven. The procedure requires that the assembled PVC discs, filters, shrinkable tubing, and sample be placed on a support stand in an electric oven for three to four minutes at a temperature between 450–500° F. Upon removal from the oven, hose clamps are placed around each PVC disc. The method has several advantages. It saves time and expenses over conventional methods such as pneumatic pressurized core holders or triaxial testing units and preserves the original interstitial bore spaces of the

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03202.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03203.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

ISSN:0017-467X    

DOI:10.1111/j.1745-6584.1978.tb03204.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY