The Harris Matrix Composer (HMC) is a tool to build up and administer a representation of an archaeological stratification in form of a sequential diagram or Harris Matrix. Each node of the Harris Matrix refers to a unit of stratification, i.e. either a deposit or a surface of an excavation site. The edges represent the stratigraphic relations between units of stratification.

The main component of the Harris Matrix Composer is a graph editor for creating and updating a Harris Matrix throughout the entire excavation period. Users add nodes for deposits and surfaces and determine their stratigraphic relations by drawing edges. The application supports valid Harris Matrix creation and indicates illegal nodes and edges.

In addition to stratigraphic relations, temporal can be added by drawing special edges. A unit can be either later than another one or they can be both contemporary. Phases define structural relations, like posts or postholes of a dwelling. Periods also define temporal relations, i.e. deposits and surfaces that are assigned to the same epoch.

It is planned to develop an interface to the GIS system ArcGIS to access stratigraphic layers for visualization and analysis by selecting units of the Harris Matrix. This however depends on the capabilities of the ArcGIS API, which will be investigated in a follow up project.

More details can be found at the Harris Matrix Composer web site.