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J.A. Kingsbury

Publications and source records attributed to J.A. Kingsbury.

6 recordsLinked to original sources

Relation between flow and temporal variations of nitrate and pesticides in two karst springs in northern Alabama

Two karst springs in the Mississippian Carbonate Aquifer of northern Alabama were sampled between March 1999 and March 2001 to characterize the variability in concentration of nitrate, pesticides, selected pesticide degradates, water temperature, and inorganic constituents. Water temperature and inorganic ion data for McGeehee Spring indicate that this spring represents a shallow flow system with a relatively short average ground-water residence time. Water issuing from the larger of the two springs, Meridianville Spring, maintained a constant temperature, and inorganic ion data indicate that this water represents a deeper flow system having a longer average ground-water residence time than McGeehee Spring. Although water-quality data indicate differing short-term responses to rainfall at the two springs, the seasonal variation of nitrate and pesticide concentrations generally is similar for the two springs. With the exception of pesticides detected at low concentrations, the coefficient of variation for most constituent concentrations was less than that of flow at both springs, with greater variability in concentration at McGeehee Spring. Degradates of the herbicides atrazine and fluometuron were detected at concentrations comparable to or greater than the parent pesticides. Decreases in concentration of the principal degradate of fluometuron from about July to November indicate that the degradation rate may decrease as fluometuron (demethylfluometuron) moves deeper into the soil after application. Data collected during the study show that from about November to March when recharge rates increase, nitrate and residual pesticides in the soil, unsaturated zone, and storage within the aquifer are transported to the spring discharges. Because of the increase in recharge, fluometuron loads discharged from the springs during the winter were comparable to loads discharged at the springs during the growing season. ?? 2008 American Water Resources Association.

Journal of the American Water Resources Associatio

Water Resources of the Duck River Watershed, Tennessee

The U.S. Geological Survey began a study in 2003 in cooperation with the Tennessee Duck River Development Agency to assess the hydrology of the Duck River watershed from Normandy Dam downstream to Columbia, Tennessee. Ground-water-level data, spring-flow, bacteria samples, and streamflow were collected during this study to characterize the hydrology of the study area. The emphasis of this study was to characterize the temporal and spatial variability of the various components that make up streamflow in the Duck River in this study area. Water-level data from wells in the study area indicate a good hydraulic connection between the aquifer and the river, with little long-term storage of water following recharge events. Variations in spring flow and ground-water temperature at springs indicate that a large component of water issuing from springs has a short residence time in the aquifer for most of the springs monitored in the study area. Escherichia coli densities in samples collected from springs are similar to concentrations in samples from tributaries and the Duck River. Base-flow synoptic discharge measurements, flow-duration analysis of tributary streams, and streamflow accounting analysis indicate the portion of the watershed between Pottsville and Columbia yields more water than the portion between Shelbyville and Pottsville. Base-flow synoptic measurements show that Fountain Creek yields more water than other tributary basins in the study area, whereas base-flow synoptic measurements on the mainstem indicate that streamflow in the Duck River between Pottsville and Columbia could vary by 10 percent as the result of gaining and losing reaches. These results are applicable for average flow conditions that occurred during the study. Flow-duration analysis indicates that tributaries in this part of the watershed have a large component of ground-water contributing base flow. Streamflow accounting analysis for two periods of extended recession was used to determine the contributions of flow releases from Normandy Dam, tributaries, wastewater discharges, and ground-water discharge. The analysis indicated this same section of the mainstem of the Duck River between Pottsville and Columbia had as much as four times more ground-water discharge as sections upstream from Pottsville.

Scientific Investigations Report

Monazite paragenesis and U-Pb systematics in rocks of the eastern Mojave Desert, California, U.S.A.: implications for thermochronometry

Studies of the paragenesis and U-Pb systematics of monazite in rocks from the eastern Mojave Desert, California, corroborate its potential usefulness as a prograde thermochronometer and in dating granite inheritance. Unmetamorphosed Latham Shale and its equivalents at grades ranging from greenschist to upper amphibolite facies are virtually identical in composition. Monazite is absent in the shale and low-grade schists, but it is abundant in schists at staurolite and higher grades. Lower-grade schists instead include minute Th- and Ce-oxides and unidentified Ce-poor LREE-phosphates that apparently are lower-temperature precursors to monazite. Thus monazite originates when the pelite passes through lower-amphibolite-facies conditions. Monazites from three Upper Cretaceous granites yield ages that are strongly discordant. Upper intercepts of 1.6-1.7 Ga are similar to those defined by U-Pb data for coexisting zircons and coincide with a period of copious magmatism in the Mojave crust. As the host Upper Cretaceous granitic magmas were all above 700??C, effective closure of the restitic monazites to Pb loss must be well in excess of this temperature. U-Pb compositions of monazite from Proterozoic granitoids and schist also indicate high Pb retentivity. Taken together, these studies support the suggestion that monazite can be an effective prograde thermochronometer. At least in pelites, it is not usually retained as a detrital mineral, but rather forms during moderate-temperature metamorphism. Its U-Pb system should not be reset by subsequent higher-grade metamorphism. ?? 1993.

Chemical Geology

Hydrogeology, ground-water quality, and potential for water-supply contamination near an abandoned wood-preserving plant site at Jackson, Tennessee

Hydrogeologic and ground-water-quality data were collected near an abandoned wood-preserving plant site at Jackson, Tennessee to determine the extent and magnitude of ground-water contamination in offsite areas and to assess the potential for contamination of nearby water-supply wells. New methods were used to collect ground-water samples from the alluvial aquifer at six offsite stations at depths of less than about 40 feet below land surface. In addition, 36 offsite wells were installed at these stations to collect samples from the alluvial aquifer and to depths of about 150 feet in the deeper Fort Pillow aquifer. Ground-water samples collected by the new methods and from the 36 offsite wells were analyzed for selected volatile and semi-volatile compounds. The samples collected from the 36 wells also were analyzed for major and trace inorganic constituents. Naphthalene and some volatile organic compounds were detected at low concentrations in samples from both the alluvial aquifer and the Fort Pillow aquifer. To assess the potential for water-supply contamination from the site, four water-supply wells to the east (upgradient) and three wells to the west (down- gradient) of the abandoned plant site were sampled. These samples were analyzed for the same analytes as the samples from the 36 wells. Although volatile organic compounds and elevated concentrations of trace and major inorganic constituents were measured in samples from some wells east of the site, no organic compounds associated with the wood- preserving process were detected. No contaminants from the site were detected in samples from wells west of the site.

Water-Resources Investigations Report