Ferromanganiferous Soil Concretions: A Scanning Electron Microscope Study of Their Micropore Structures

Abstract

Abstract The micropore structures of zoned and nonzoned concretions which occur together in the plow‐depth layer of Flanagan silt loam were examined by scanning electron microscopy. The concretions were characterized by a dominance of small irregularly shaped pores having dimensions varying from 0.2 to 2 µ. Some large pores with dimensions of 2 to 3 µ were observed. The concretion fabric components, for the most part, were masked by massive plasmic depositions indicating that much of the original matrix porosity had probably been infilled during concretion formation. The magnitude of infilling and reduction in original matrix porosity, judged from the frequency and distribution of various sized pores, appeared to be similar for zoned and nonzoned concretions.