Barium in Illinois Surface Soils
1986
Jones, Robert L.
The mean total Ba content determined in 174 upland, surface soil samples was 610 mg kg⁻¹ and the contents of the samples formed a normal distribution. An isopleth map of Ba contents was produced from programs calculating contours on a grided surface overlaid on a base map of Illinois. The isopleths are related to loess isopachs in southern Illinois and uniformly decrease from about 700 mg kg⁻¹ near the Mississippi River to near 500 mg kg⁻¹ at the eastern boundary of the state. This change in Ba content may reflect both weathering intensity and aeolian sorting of Ba-bearing minerals. In northwestern Illinois where loess is also an important parent material, Ba contents are rather invariant in the range 600 to 650 mg kg⁻¹. Where loess is very thin or nonexistent, surface soils of northeastern Illinois contain about 500 mg kg⁻¹, a content thought to reflect the concentration in the tills of this area.
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