Elemental concentrations soil units

Shacklette H.T., Boemgen J.G. Element concentrations in soils and other surficial materials of the conterminous United States an account of the concentrations of 50 chemical elements in samples of soils and other regoliths. Washington, 1984. 

Smith, D.B., Cannon, W.F., Woodruff, L.G., Garrett, R.G., Klassen, R.D., Kilburn, J.E., Horton, J.D., King, H.D., Goldhaber, M.B., Morrison, J.M. 2005. Major- and trace-element concentrations in soils from two continental-scale transects of the United States and Canada. U.S. Geological Survey Open-File Report 2005-1253. 

Forty-two soil samples were taken for analysis from difierent soil units of six exposures. The primary grouping of the analytical data was made by the soil units distinguished in the field (Figure 3). Table II contains the analytical data expressed as elemental concentration means and standard deviations for five major elements and nine minor and trace elements for the five soil units. Complete data are available from the authors on request. In addition. Units II and III have been subdivided on stratigraphic and chemical grounds. Unit II consists of Ko-e and its associated Apb. Because Ko-e is discontinuous. Unit IF is the second soil unit in those sections where Ko-e is missing from the exposure. 

The rare earth element (REE) concentrations show similar patterns when the samples are grouped by soil units. Results, expressed as elemental concentration means and standard deviations, are displayed in Table III. There are three main points of interest ... 

Many nonessential trace elements are found in the body. Depending on the local environment, at least 43 elements are normally incorporated into developing teeth another 25 elements are seen less frequently. The rest, notably the heavy metals, have never been detected in teeth. Many trace elements, particularly the heavy metals, are considered when testing for metal poisoning. Many plants concentrate essential and nonessential elements from soil and water, including aluminum (several species of subtropical plants), selenium (many plants), strontium (mesquite beans), and lithium (wolfberries, used by Native Americans in the southwestern United States for jam). Ingestion of these plants can cause toxicity for the element involved. 

Chaklette, T. H, Boemgen, J. C. (1984). Element Concentration in Soils and Other Surficial Materials of the Conterminous United States. U.S. Geological Survey Prof. Paper No. 574-C. Washington, 1-39. 

Fig. 7-23. Scatter diagrams for iron, titanium, magnesium, calcium, vanadium, and chromium in the atmospheric aerosol versus aluminum as reference element. Concentrations are given in units of ng/ m3. Symbols indicate the type of sampling site O marine, A marine-influenced, 9 remote continental, Antarctic. The range of X/Al ratios in crustal rock is shown by the solid lines and X/Al ratios in soil by the dashed lines. [Adapted from Rahn (1975b).]...

FIGURE 7.4 Abundance of the most important elements in soils (black bars) and in the earth s crust (grey bars) in (a) mass units (logarithm of concentration, in parts per million) and (h) molar units (logarithm of concentration in millimoles per kilogram). 

Uranium is a naturally occurring radioactive element that is present in nearly all rocks and soils it has an average concentration in U.S. soils of about 2 pCi/g (3 ppm) (du Preez 1989 NCRP 1984a). Some parts of the United States, particularly the western portion, exhibit higher than average uranium levels due to natural geological formations. Most uranium ores contain between 0.05 and 0.2% uranium, up to 1,000 times the levels normally found in soil (Uranium Institute 1996). 

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