Harris Matrix

The Harris matrix is a method for recording and diagramming the stratigraphic sequence of an archaeological site as a partial-order diagram of individually defined contexts. Devised by Edward C. Harris at the Winchester excavations in 1973 and codified in his Principles of Archaeological Stratigraphy, it treats every deposit, cut, and interface as a separate stratigraphic unit and reduces the tangle of physical relationships among them to a minimal directed acyclic graph that expresses only relative temporal order. By distinguishing physical superposition from temporal sequence and stripping away redundant relationships through transitive reduction, the matrix turns the three-dimensional complexity of a dig into a single, auditable diagram. It is the structural backbone of single-context recording and the standard interface between excavation and chronological modeling.