Monday, November 13, 2006
101-11

Pedogenesis of Highly Ferromanganiferous Soils in the Maryland Piedmont.

Rebecca R. Blank and Martin Rabenhorst. Univ of Maryland, College Park, 1112 H. J. Patterson Hall, College Park, MD 20742

Soils in the Mid-Atlantic region typically contain <50 g kg-1 Fe (as Fe oxides) and usually only one-fiftieth that amount (<1 g kg -1) Mn (as Mn oxides). However, soils have been discovered in the western portion of the Piedmont physiographic province that contain >170 g kg-1 Fe and 100-150 g kg-1 Mn. These exceptionally high levels of Fe(III)(hydr)oxides and Mn(III, IV)(hydr)oxides impart an extremely dark color to the soil material (moist Munsell value and chroma commonly <2/1). The pedogenesis of these soils is not yet understood; however, they seem to occur in areas of complicated metamorphic geology and particularly in association with marble or other calcareous bedrock. These soils are of interest because Mn(III,IV)(hydr)oxides are highly reactive minerals, having a high sorption potential and large specific surface, and the ability to participate in oxidation-reduction reactions. This paper will demonstrate the general extent of these unusual ferromanganiferous soils by combining various digital spatial data sets (including soil survey, geology, and topography) with a field reconnaissance assessment. The soils will be examined along topographic transects to assess their areal extent and range in properties. Morphological, micromorphological, physical, chemical and mineralogical data will be acquired and reported.

Handout (.pdf format, 506.0 kb)
Handout (.pdf format, 716.0 kb)