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J. L. Ryder

Publications and source records attributed to J. L. Ryder.

12 recordsLinked to original sources
USGS1996

Surface-water-quality assessment of the lower Kansas River basin, Kansas and Nebraska: Selected metals, arsenic, and phosphorus in streambed sediments of first- and second-order streams, 1987

The occurrence and geographic distribution of major metals and trace elements was assessed in the lower Kansas River Basin of Kansas and Nebraska by studying the concentrations of metals and nonmetallic elements in the less-than 63-micrometer-sized fraction of streambedsediment samples from 422 sites on first- and second-order streams. Median concentrations were the same order of magnitude as the geometric mean concentrations in soils of the western United States. Either threshold concentrations or upper percentile classes (greater than 50 percent of concentrations) were determined for 14 metals, arsenic, and phosphorus. Threshold concentrations were determined as the point that the slope of a normal-probability plot increases, indicating data from two different populations. Samples with a concentration greater than the threshold concentration indicated possible enrichment with respect to that particular element. Concentrations of the transition metals, which included chromium, cobalt, copper, manganese, nickel, and vanadium, generally were larger in the southeastern part of the study unit where Permian and Pennsylvanian shale and limestone predominate. The largest concentrations of the alkali metals, potassium and sodium, mainly were in the northwestern part of the study unit, which is an area of Quaternary loess deposits irrigated with ground water. Large concentrations of the alkaline-earth metal, barium, also were in the northwestern part of the study unit. Concentrations of the other alkaline-earth metals, calcium, magnesium, and strontium, were larger in the southern part of the basin, which is underlain by Permian and Pennsylvanian shale and limestone. The largest concentrations of arsenic and lead were mainly in the southeastern part of the study unit, an area of Permian and Pennsylvanian shale. Large concentrations of phosphorus in the northwestern part of the study unit probably were due to runoff from irrigated agricultural lands.

Kansas, Nebraska↗
USGS1990

Production of sulfur gases and carbon dioxide by synthetic weathering of crushed drill cores from the Santa Cruz porphyry copper deposit near Casa Grande, Pinal County, Arizona

Samples of ground drill cores from the southern part of the Santa Cruz porphyry copper deposit, Casa Grande, Arizona, were oxidized in simulated weathering experiments. The samples were also separated into various mineral fractions and analyzed for contents of metals and sulfide minerals. The principal sulfide mineral present was pyrite. Gases produced in the weathering experiments were measured by gas chromatography. Carbon dioxide, oxygen, carbonyl sulfide, sulfur dioxide and carbon disulfide were found in the gases; no hydrogen sulfide, organic sulfides, or mercaptans were detected. Oxygen concentration was very important for production of the volatiles measured; in general, oxygen concentration was more important to gas production than were metallic element content, sulfide mineral content, or mineral fraction (oxide or sulfide) of the sample. The various volatile species also appeared to be interactive; some of the volatiles measured may have been formed through gas reactions.

Journal of Geochemical Exploration↗
USGS1988

EFFECTS OF METEOROLOGICAL CHANGES ON CONCENTRATIONS OF HELIUM, CARBON DIOXIDE, AND OXYGEN IN SOIL GASES.

Samples were collected from a hollow probe at 0. 75-m depth and from a plastic hemisphere on the ground surface. Soil temperature, air temperature, percent humidity, and barometric pressure were also measured. Soil moisture was measured only indirectly as amount of rain or snowfall. Higher concentrations of CO//2 in both the 0. 75-m and surface samples correlated with higher soil and air temperatures, which suggests that CO//2 was produced by bacteria. Lower concentrations of helium in both the 0. 75-m and surface samples correlated with higher soil and air temperatures. Rain and snowfall appear to affect helium concentrations.

Conference Paper↗