Soil Horizons
Compiled by Mark Francek (more info) at Carleton College (more info) (SERC) and Central Michigan University (more info)
Find animations illustrating the development of soil horizons and their characteristics.
Soil Horizon Formation, Wiley (more info) This animation illustrates the process of eluviation which is important in determining the physical and chemical characteristics of the O, A, and E horizons. In later frames, the process of illuviation is depicted, with the B horizon becoming enriched with clays transported from upper horizons. Users with slow connections can expect long loading times.
BioMantle and Soil Thickness Processes, University of Illinois ( This site may be offline. ) This Flash animation outlines in four stages the processes of soil thickening and thinning. A special focus is the changing role of termites, ants, worms, and vertebrates like moles in soil mixing. Rolling your mouse over technical terms accesses a glossary. Clicking on timeline markers at the bottom of the page allows review of any of the four development stages.
Typical Progression of Soil Profile Development, North Carolina State University (more info) This Flash animated slide show hypothetical 100,000 year soil profile development from bedrock in a warm, humid climate. The weathering front progresses downward with time as does the accumulation of clays and iron oxides. Eventually, well formed O, A, Bw, C, and R horizons are present. Note that accompanying left slide descriptions are sometimes cut off.
