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Hansford T. Shacklette

Publications and source records attributed to Hansford T. Shacklette.

17 recordsLinked to original sources
USGS1984

Element concentrations in soils and other surficial materials of the conterminous United States

Samples of soils or other regoliths, taken at a depth of approximately 20 cm form locations about 80 km apart, throughout the conterminous United States, were analyzed for their content of elements. In this manner, 1,318 sampling sites were chosen, and the results of the sample analyses for 50 elements were plotted on maps. The arithmetic and geometric mean, the geometric deviation, and a histogram showing frequencies of analytical values are given for 47 elements. The lower concentrations of some elements (notable, aluminum, barium, calcium, magnesium, potassium, sodium, and strontium) in most samples of surficial materials from the Eastern United States, and the greater abundance of heavy metals in the same materials of the Western United States, indicates a regional geochemical pattern of the largest scale. The low concentrations of many elements in soils characterize the Atlantic Coastal Plain. Souls of the Pacific Northwest generally have high concentrations of aluminum, cobalt, iron, scandium, and vanadium, but are low in boron. Soils of the Rocky Mountain region tend to have high concentrations of copper, lead, and zinc. High mercury concentrations in surficial materials are characteristic of Gulf Coast sampling sites and the Atlantic coast sites of Connecticut, Massachusetts, and Maine. At the State level, Florida has the most striking geochemical pattern by having soils that are low in concentrations of most elements considered in this study. Some smaller patterns of element abundance can be noted, but the degree of confidence in the validity of these patterns decreases as the patterns become less extensive.

Conterminous United States↗
USGS1983

Biogeochemical sampling in the Mahd Adh Dhahab District, Kingdom of Saudi Arabia

A biogeochemical reconnaissance of the Mahd adh Dhahab district, Kingdom of Saudi Arabia, confirms the ability of deep-rooted Acacia trees to reflect bedrock concentrations of some trace elements. The analytical values for lead, zinc, selenium, and cadmium in ash of tree branches are significantly higher in samples from areas of known mineralization (13 sites) than in samples from areas of no known mineralization (12 sites). Geometric mean concentrations of these elements in the two areas (mineralized; nonmineralized), quoted as parts per million in ash, are lead (122; 28), zinc (713; 443), selenium (1.2; 0.6), and cadmium (1.4; 0.5). The range of molybdenum values in ash from the two areas is similar, but a cluster of four sites in an area classified as nonmineralized corresponds to an area where the U.S. Geological Survey reported anomalous molybdenum values in rock in 1965. Results for other elements were either equivocal (mercury, tellurium, silver) or showed no correspondence to the two areas. Mean values for barium, manganese, potassium, and sodium are significantly higher in areas of no known mineralization, but we conclude that this reflects a difference in country rock major-element chemistry rather than the effect of ore-forming processes. The pattern of trace-metal values in Acacia ash is present whether the sampled tree grows on bedrock, on talus, or on residual or modern alluvium. This fact suggests that the trace-element chemistry of the trees reflects bedrock geochemistry and implies that Acacia biogeochemistry could be applied as a prospecting tool in areas where bedrock is not well exposed.

Open-File Report↗
USGS1974

Selenium, fluorine, and arsenic in surficial materials of the conterminous United States

Concentrations of selenium, fluorine, and arsenic in 912, 911, and 910 samples, respectively, of soils and other regoliths from sites approximately 50 miles (80 km) apart throughout the United States are represented on maps by symbols showing five ranges of values. Histograms of the concentrations of these elements are also given. The geometric-mean concentrations (ppm) in the samples, grouped by area, are as follows: Selenium-- Entire United States, 0.31; Western United States, 0.25; and Eastern United States, 0.39. Fluorine-- Entire United States, 180; Western United States, 250; and Eastern United States, 115. Arsenic-- Entire United States, 5.8; Western United States, 6.1; and Eastern United States, 5.4.

Circular↗
USGS1973

Lithium in surficial materials of the conterminous United States and partial data on cadmium

Concentrations of lithium in 912 samples of soils and other regoliths from sites approximately 50 miles apart throughout the United States are represented on a map by symbols showing five ranges of values. A histogram of the lithium concentrations is also given. The geometric mean lithium concentration is 20.4 ppm (parts per million) for all samples, 17.3 ppm for samples from the Eastern United States, and 23.3 ppm for samples from the Western United States. Cadmium concentrations were less than 1 ppm in all but 11 of the 912 samples. Ten of these 11 samples contained from 1 to 1.5 ppm cadmium; one sample contained 10 ppm cadmium.

Circular↗