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J. A. Erdman

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

At least 19 recordsLinked to original sources
USGS2002

Mineral composition of small-grain cultivars from a uniform test plot in South Dakota

Seventy-five cultivated varieties (cultivars) of hard red spring wheat (HRS), hard red winter wheat (HRW), durum wheat, oats, and barley were harvested in 1974 from a small-grain trial plot in Harding County, SD, just north of Buffalo. Analysis of the grains reported here includes crude protein for only the wheat cultivars, ash yield, and 17 chemical elements, many of which are not commonly given in the literature (such as B, Cd, Mo, Ni, and Se). Differences in composition between the two classes of hard red wheat indicate that HRS is significantly higher (p < 0.05) than HRW in protein content, ash yield, Ca, K, Mg, Na, P, total S, Sr, and Zn; Cd is significantly higher in the HRW cultivars. For the most part, concentrations were quite uniform within all grain types. Only two cultivars were anomalous: cv. Hi Plains in HRW wheats and cv. Astro in the oat group.

Journal of Agricultural and Food Chemistry↗
USGS1988

Gold and other metals in big sagebrush (Artemisia tridentata Nutt.) as an exploration tool, Gold Run District, Humboldt County, Nevada

Big sagebrush — a cold-desert species that dominates the terrain over large parts of western United States — was sampled along several traverses that crossed thermally metamorphosed limestone, phyllitic shale, and schist of the Middle and Upper Cambrian Preble Formation that host skarn-, disseminated gold and silver-, and hot springs gold-type mineral occurrences. Patterns of detectable levels of gold (8 to 28 ppb or ng g −1 ) in ash of new growth were consistent with areas affected by known or suspected gold mineralization. Soils collected along one of the traverses where a selenium-indicator plant was common contained no gold above background levels of 2ppb, but were consistently high in As, Sb, and Zn, and several samples were unusually high in Se (maximum 11 ppm or μg g −1 ). Sagebrush along this traverse contained Li at levels above norms for this species. We also found a puzzling geochemical anomaly at a site basinward from active hot springs along a range-front fault scarp. Sagebrush at this site contained a trace of gold and an unusually high concentration of Cd (13 ppm) and the soil had anomalous concentrations of Cd and Bi (3.2 and 6 ppm, respectively). The source of this anomaly could be either metal-rich waters from an irrigation ditch or leakage along a buried fault. Despite the limited nature of the study, we conclude that gold in sagebrush could be a cost-effective guide to drilling locations in areas where the geology seems favorable for disseminated and vein precious metals.

Journal of Geochemical Exploration↗
USGS1985

Remotely sensed limonite anomaly on Lordsburg Mesa, New Mexico: Possible implications for uranium deposits

We have identified a large, anomalously limonitic area in Cenozoic gravels on Lordsburg Mesa near Lordsburg, New Mexico, using Landsat images. Our interpretation of the geophysical and geochemical data suggests the exploration hypothesis that the Lordsburg Mesa limonite anomaly is the surface expression of a chemical trap that may contain concentrations of uranium similar to calcrete-uranium deposits. Ground water originating in the Big Burro Mountains, where uranium vein deposits are known, drains through the Lordsburg Mesa area. This ground water is apparently forced near the surface by a buried bed-rock ridge along the west side of the limonite anomaly. The resulting changes in ground-water chemistry may be precipitating uranium along the eastern margin of the limonite anomaly.

Economic Geology↗