BIOMANTLE EVOLUTION AND THE REDISTRIBUTION OF EARTH MATERIALS AND ARTIFACTS

Abstract

A biomantle is a differentiated zone in the upper part of soils produced largely by bioturbation, but often aided by subsidiary processes. One such process is loss of fine particles and redistribution of coarse ones from evolving biomantles. This is accomplished by rainwash and wind sorting of unprotected surface mounds and by vertical and/or lateral eluviation (lessivage) through-flow processes. Also subsidiary are the various processes by which iron, manganese, and other concretions come to reside in some biomantles. Concretions may form in biomantles directly from metal-bearing solutions, they may enter biomantles from upslope via creep and slope processes, or they may enter biomantles from below as the landscape down-wastes. Faunalmantles are biomantles produced largely by burrowing animals (faunalturbation), and floralmantles are produced largely by tree uprooting (floralturbation). Faunalmantles and floralmantles may be one-, two-, or multilayered, as differentiated by one or more observable or measurable soil properties. Chief among these properties are particle size and biologically produced soil fabric (biofabric). Complex biomantles result where faunal-mantles and floralmantles are conjoined or coevolve on the same tract or landscape. Stone zones, stone lines, or coarse-textured layers comprise the lower members of two-layered and multilayered faunal-mantles, and stone pavements comprise the upper members of two-layered and multi-layered floralmantles. Prehistoric and historic artifacts may be components of some floralmantle pavements and of some faunalmantle some lines and stone zones.