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R. E. Rathbun

Publications and source records attributed to R. E. Rathbun.

47 records · Page 3Linked to original sources

Traveltime, unit-concentration, longitudinal-dispersion, and reaeration characteristics of upstream reaches of the Yampa and Little Snake Rivers, Colorado and Wyoming

Measurements were made along a 58-mile reach of the Yampa River in Colorado and a 77-mile reach of the Little Snake River in Colorado and Wyoming to determine traveltime, unit-concentration , and longitudinal-dispersion characteristics. Two traveltime, unit-concentration, and dispersion analyses were made along the Yampa River when its average streamflow was approximately 100 and 3,400 cu ft/s; three traveltime, unit-concentration, and dispersion analyses were made along the Little Snake River when its average streamfow was approximately 200, 600, and 1,600 cu ft/s. Reaeration coefficients were determined only for the Yampa River, when its average streamflow was approximately 100 cu ft/s. Traveltime and unit-concentration simulations were made using a mathematical model. Data collected for the Little Snake River when the average streamflow was approximately 600 cu ft/s were used as a check of model-simulation accuracy. Traveltime simulations compared to within 5%, and unit-concentration simulations were within 30 to 40% of the measured flow data. Longitudinal-dispersion coefficients ranged from 400 to 6,050 sq ft/s for the two streams. Reaeration coefficients for the Yampa River, adjusted to 20 degrees celsius, ranged from 6.04 to 33.4 per day. Two semi-empirical equations gave reaeration coefficients in best agreement with measured reaeration coefficients. Absolute errors of estimate for these equations were 11.8 and 17.3%. (USGS)

Water-Resources Investigations Report↗

Estimating the gas and dye quantities for modified tracer technique measurements of stream reaeration coefficients

Measuring the reaeration coefficient of a stream with a modified tracer technique has been accomplished by injecting either ethylene or ethylene and propane together and a rhodamine-WT dye solution into the stream. The movement of the tracers through the stream reach after injection is described by a one-dimensional diffusion equation. The peak concentrations of the tracers at the downstream end of the reach depend on the concentrations of the tracers in the stream at the injection site, the longitudinal dispersion coefficient, the mean water velocity, the length of the reach, and the duration of the injection period. The downstream gas concentrations also depend on the gas desorption coefficients of the reach. The concentrations of the tracer gases in the stream at the injection site depend on the flow rates of the gases through the injection diffusers, the efficiency of the gas absorption process, and the stream discharge. The concentration of dye in the stream at the injection site depends on the flow rate of the dye solution, the concentration of the dye solution, and the stream discharge. Equations for estimating the gas flow rates, the quantities of the gases, the dye concentration, and the quantity of dye together with procedures for determining the variables in these equations are presented. (Woodard-USGS)

Water-Resources Investigations Report↗

Transport and dispersion of fluorescent tracer particles for the dune-bed condition, Atrisco Feeder Canal near Bernalillo, New Mexico

A fluorescent tracer technique was used to study the rates of transport and dispersion of sediment particles of various diameters and specific gravities for a dune-bed condition in an alluvial channel, Atrisco Feeder Canal near Bernalillo, N. Mex. The total transport rates of bed material measured by the steady-dilution and spatial-integration procedures were within the range of transport rates computed by the modified Einstein procedure. Lateral dispersion of the tracer particles increased with increase in the size of the tracer particles, whereas longitudinal dispersion decreased. The velocities of the tracer particles decreased with increase in the size of the tracer particles; dependence on particle diameter was large for the small particles, small for the large particles. Tracers were found at larger depths in the bed than would be expected on the basis of the sizes of the dunes in the channel. (Woodard-USGS)

Professional Paper↗

Comparison of the radioactive and modified techniques for measurement of stream reaeration coefficients

The radioactive and modified tracer techniques were used to measure the reaeration coefficients of two reaches each of Black Earth Creek and the Madison Effluent Channel near Madison, Wis. Comparison of the results showed that coefficients measured with the modified technique ranged from -8.96 to +3.61 and from +15.7 to +32.2 percent different from the coefficient measured with the radioactive tracer technique on the two reaches of Black Earth Creek. The larger coefficients measured with the modified technique on the second reach were attributed to increased wind conditions during the latter part of the modified-technique experiment. Interpretation of the results of the Madison Effluent Channel study was complicated by an unsteady flow condition during the modified-technique experiment. It was necessary to estimate the part of the reduction in the area under the dye concentration-versus-time curve that was the result of dye loss and the part that was the result of the increase in water discharge. Using these estimated values, the coefficients measured with the modified technique ranged from +25.3 to +57.9 and from -4.74 to +2.94 percent different from the coefficient measured with the radioactive technique on the two reaches of the Madison Effluent Channel. Reaeration coefficients were predicted for the 4 stream reaches with 19 predictive equations from the literature. The range of the predicted coefficients for each of the reaches varied from about a 6-fold range for the first reach of the Madison Effluent Channel to an almost 11-fold range for the second reach of Black Earth Creek. There are advantages and disadvantages to both the radioactive and modified tracer techniques. The main advantage of the radioactive technique is that the tracer gas is chemically inert; the main disadvantage is that a radioactive isotope of the gas must be used to obtain the necessary analytical sensitivity. The main advantage of the modified technique is that radioactive tracers are not necessary; the main disadvantage is that the hydrocarbon tracer gases may be subject to biological degradation and sorption losses. Results of this comparison study suggest that the modified technique is a promising alternative to the use of radioactive tracers.

Wisconsin↗

Transport and dispersion of fluorescent tracer particles for the dune-bed condition, Atrisco Feeder Canal near Bernalillo, New Mexico

A tracer technique in which mineral particles were coated with fluorescent dyes was used to study the rates of transport and dispersion of sediment particles`of various diameters and specific gravities for a dune-bed condition in an alluvial channel. The experiment was conducted in the Atrisco Feeder Canal near Bernalillo, N. Mex., between May 1 and July 14, 1967. A continuous point source of tracers, approximated by injections at 5- or 10-minute intervals, was maintained for 7 days so that the steady-dilution procedure could be used to calculate the transport rate of bed material. After termination of the injection process, the spatial-integration procedure was used to follow the movement of the tracers downstream and to calculate the transport rate. Samples of the bed material in transport and the accompanying tracers moving along the surface of the dune bed were obtained periodically throughout the study with the "dustpan" sampler especially designed for fluorescent tracer studies. In addition, the spatial distributions of the tracers in the dune bed were determined three times during the study by core sampling.

New Mexico↗

Determination, storage, and preservation of low molecular weight hydrocarbon gases in aqueous solution

A gas chromatograph with a flame ionization detector was used in conjunction with a stripping chamber and cold trap apparatus to measure microgram-per-litre quantities of low molecular weight hydrocarbon gases in water samples. Glass bottles with ground-glass stoppers were used to store the samples. Formalin was added to stop bacterial activity and preserve samples with no measurable losses for as much as 7 days.

Journal of Research of the U.S. Geological Survey↗