Geology topics

R.F. Middelburg

Publications and source records attributed to R.F. Middelburg.

4 recordsLinked to original sources

USGS1987

User's manual for estimation of dissolved-solids concentrations and loads in surface water

Dissolved solids in surface water are an important indicator of overall water quality. Ordinarily, dissolved-solids concentrations and loads are estimated by indirect methods that are based on periodic chemical analyses. Three computer programs , FLAGIT, DVCOND, and SLOAD, were developed to provide a consistent and accurate method of estimating dissolved-solids concentrations and loads. FLAGIT retrieves daily values of specific conductance and discharge and periodic water quality analyses from the U.S. Geologic Survey 's National Water Data Storage and Retrieval System data base, deletes incomplete data, and flags possible data errors. DVCOND fills in missing daily values of specific conductance, when appropriate, by linear interpolation. Using water quality data, SLOAD computes 3 yr moving regressions of dissolved-solids loads as a function of specific conductance and discharge. SLOAD then applies the regression coefficients to the daily values data to estimate daily dissolved-solids loads that are summed by month and by year. Separate regressions are used to estimate the mass fractions of six major ions. The theoretical basis and underlying assumptions of the procedures are presented, with documentation of the programs and their use. (USGS)

Water-Resources Investigations Report↗

USGS1986

GOES data-collection system instrumentation, installation, and maintenance manual

The purpose of the manual is to describe the installation, operation, and maintenance of Geostationary Operational Environmental Satellite (GOES) data collection platforms (DCP's) and associated equipment. This manual is not a substitute for DCP manufacturers ' manuals but is additional material that describes the application of data-collection platforms in the Water Resources Division. Power supplies, encoders, antennas, Mini Monitors, voltage analog devices, and the installation of these at streamflow-gaging stations are discussed in detail. (USGS)

Open-File Report↗

USGS1985

Ground-water contribution to the salinity of the Upper Colorado River Basin

A study was conducted to estimate the contribution of groundwater and other natural sources to the salinity of streamflow in the Upper Colorado River Basin. Salt-load estimates were derived from a mass balance using measurements of quantity and quality of base streamflow. Groundwater inflow was considered to represent the bulk of the streamflow during the low-flow winter months. (USGS)

Water-Resources Investigations Report↗

USGS1984

Trend analysis of salt load and evaluation of the frequency of water-quality measurements for the Gunnison, the Colorado, and the Dolores rivers in Colorado and Utah

Monthly values were computed for water-quality constituents at four streamflow gaging stations in the Upper Colorado River basin for the determination of trends. Seasonal regression and seasonal Kendall trend analysis techniques were applied to two monthly data sets at each station site for four different time periods. A recently developed method for determining optimal water-discharge data-collection frequency was also applied to the monthly water-quality data. Trend analysis results varied with each monthly load computational method, period of record, and trend detection model used. No conclusions could be reached regarding which computational method was best to use in trend analysis. Time-period selection for analysis was found to be important with regard to intended use of the results. Seasonal Kendall procedures were found to be applicable to most data sets. Seasonal regression models were more difficult to apply and were sometimes of questionable validity; however, those results were more informative than seasonal Kendall results. The best model to use depends upon the characteristics of the data and the amount of trend information needed. The measurement-frequency optimization method had potential for application to water-quality data, but refinements are needed. (USGS)

Water-Resources Investigations Report↗