Microstratigraphy

Microstratigraphy is the study of stratigraphic relationships at microscopic scales, focusing on the fine-scale organization of soils, sediments, and archaeological deposits. It seeks to reveal how layers form, interlock, and are modified by processes such as deposition, reworking, bioturbation, burning, and human activity. The approach emphasizes micromorphology and the analysis of ground masses in thin sections to identify subtle interfaces, laminations, and micro-features that are not evident at macroscopic scales.

Methodologically, microstratigraphy relies on preparing and examining thin sections of the material, often under polarized light, to characterize mineral components, textures, and pore spaces. Complementary techniques include scanning electron microscopy, energy-dispersive X-ray spectroscopy, and increasingly, X-ray microtomography. The goal is to reconstruct a sequence of micro-events and to describe microstratigraphic units and features such as micro-laminations, voids, microcrystal growth, inclusions, and microcharcoal or phytoliths. The data are integrated with conventional stratigraphy, dating methods, and contextual archaeology or paleontology.

Applications are broad. In archaeology, microstratigraphy helps interpret site formation processes, occupational history, and the chronology of rapid events within a deposit, such as hearths, dumping episodes, or pit fills. In geology and paleoenvironmental studies, it supports high-resolution reconstructions of sedimentation, pedogenesis, and post-depositional alteration. The field is rooted in soil micromorphology and thin-section analysis and is used to provide a detailed, process-based understanding of how complex deposits accumulate and transform over time.