Abstract
Iron-manganese concretions are common in upper sola of Alfisols in the Inner Bluegrass Region of Kentucky. Their nature and quantities appear to be related to the fluctuation of seasonal perched water tables above clayey argillic horizons. This study was conducted to examine changes in the macro-and micromorphology, chemistry and mineralogy of concretions as a function of size, color and soil depth. Total Mn and Fe contents increased, while SiO2 decreased with concretion size. Black concretions contained higher Mn, while brown concretions were higher in Fe. Crystalline Mn- and Fe-oxides fractionated with a sequential extraction procedure increased, but amorphous Mn and Fe decreased with concretion size. Goethite was the only crystalline Fe oxide mineral identified by X-ray diffraction (XRD) analysis. Manganese oxide minerals were very difficult to detect due to the diffuse nature of their XRD peaks and poor crystallinity. Examination of soil thin sections showed concretions of soil horizons overlying restrictive clayey layers to exhibit differentiated fabrics, sharp external boundaries and generally spherical shapes. Concretions found within clayey restrictive layers or above lithic interfaces usually had less structural organization, softer matrices and diffuse external boundaries due to longer term saturated conditions. Scanning electron microscopy (SEM) examinations suggested that the concretionary matrix, in spite of its density, has numerous cavities and an extensive micropore system within which dissolved plasmic Fe and Mn can diffuse and precipitate.
Similar content being viewed by others
References
Bartenfelder DC, Karathanasis AD. 1988. A comparison between X-ray fluorescence and dissolution methods employing lithium metaborate fusion for elemental analysis of soil clays. Commun Soil Sci Plant Anal 19:19–492.
Barnhisel RI, Phillippe WR, Blevins RL. 1969. A simple X-ray fluorescence technique for the determination of iron and manganese in soils and concretions. Soil Sci Soc Am Proc 33:33–813.
Cescas MP, Tyner EH, Harmer III RS. 1970. Ferromanganiferous soil concretions: A scanning electron microscope study of their micropore structures. Soil Sci Soc Am Proc 34:34–644.
Drosdoff M, Nikiforoff CC. 1940. Iron-manganese concretions in Dayton soils. Soil Sci 49:49–345.
Gallaher RN, Perkins HF, Radcliffe D., 1973a. Soil concretions: I. X-ray spectrograph and electron microprobe analysis. Soil Sci Soc Am Proc 37:37–469.
Gallaher RN, Perkins HF, Tan KH, Radcliffe D., 1973b. Soil concretions: II. Mineralogical analysis. Soil Sci Soc Am Proc 37:37–472.
Jackson ML. 1956. Soil chemical analysis—Advanced course. Madison, WI: ML Jackson. 893 p.
Karathanasis AD, Hajek BF 1982. Revised methods for rapid quantitative determination of minerals in soil clays. Soil Sci Soc Am J 46:46–425.
McDaniel PA, Bathke GR, Buol SW, Cassel DK, Falen AL. 1992. Secondary manganese/iron ratios as pedochemical indicators of field-scale throughflow water movement. Soil Sci Soc Am J 56:56–1217.
McDaniel PA, Buol SW. 1991. Manganese distribution in acid soils of the North Carolina Piedmont. Soil Sci Soc Am J 55:55–158.
Murthy RS, Mathur BS. 1964. Special formation in some alluvial soil profiles of the Ganga river plain of Central Uttar Pradesh—Their origin, development and significance [abstract]. Soils Fert Abstr 31:148.
Phillippe WR, Blevins RL, Barnhisel RI, Bailey HH. 1972. Distribution of concretions from selected soils of the inner bluegrass region of Kentucky. Soil Sci Soc Am Proc 36:36–173.
Radden JA, Porter HC. 1962. Preliminary note on some soil concretions in the Virginia Piedmont. Mineral Ind J 9:9–4.
Rhoton FE, Bigham JM, Schulze DG. 1993. Properties of iron-manganese nodules from a sequence of eroded fragi-pan soils. Soil Sci Soc Am J 57:57–1392.
Rhoton FE, Meyer LD, McChesney DS. 1991. Depth of erosion assessment using Fe-Mn nodule concentrations in surface horizons. Soil Sci 152:152–394.
Ross SJ. Jr, Franzmeier DP, Roth CB. 1976. Mineralogy and chemistry of manganese oxides in some Indiana soils. Soil Sci Soc Am J 40:40–143.
Schwertmann U, Fanning DS. 1976. Iron-manganese concretions in hydrosequences of soils in loess in Bavaria. Soil Sci Soc Am J 40:40–738.
Shuman LM. 1985. Fractionation method for soil microelements. Soil Sci 140:140–22.
Soil Survey Staff. 1984. Procedures for collecting soil samples and method of analysis for soil survey. Soil Survey Invest Rep 1. Washington, DC: US GPO. 248 p.
Tokashiki Y, Dixon JB, Golden DC. 1986. Manganese oxide analysis in soils by combined X-ray diffraction and selective dissolution methods. Soil Sci Soc Am J 50:50–1084.
Uzochukwu GA, Dixon JB. 1986. Manganese oxide minerals in nodules of two soils of Texas and Alabama. Soil Sci Soc Am J 50:50–1363.
Winters Eric. 1938. Ferromanganiferous concretions from some podzolic soils. Soil Sci 46:46–40.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Zhang, M., Karathanasis, A.D. Characterization of Iron-Manganese Concretions in Kentucky Alfisols with Perched Water Tables. Clays Clay Miner. 45, 428–439 (1997). https://doi.org/10.1346/CCMN.1997.0450312
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1346/CCMN.1997.0450312