Soil Micromorphology

Soil micromorphology is the microscopic study of undisturbed soils and sediments in thin section to reconstruct how archaeological deposits formed and were altered. An oriented block is cut from a deposit without disturbing its internal structure, hardened with resin, and ground into a slice about thirty micrometers thick that can be examined under a petrographic microscope. At that scale the analyst can read features invisible in the field — the arrangement of mineral grains, microscopic charcoal and bone, plastered surfaces, dung, trampling fabrics, and the pedofeatures left by water, roots, and burrowing organisms. Developed for soil science by Walter Kubiëna and adapted for archaeology by geoarchaeologists such as Goldberg, Macphail, and Courty, micromorphology is the highest-resolution tool for interpreting site formation, occupation surfaces, and anthropogenic deposits in their original spatial context.