Once the relative and absolute chronology of the Harris Matrix is established, it should be possible to divide the site’s occupation into phases based on significant changes or breaks in the sequence. These phases will likely be defined by cultural, technological, or environmental shifts observed in the archaeological record and may very well (although not a prerequisite) be allocated to a broader period. Periods may reflect (but definitely should not contradict) the stratigraphic phasing of the matrix. Periodisation has the advantage of making the phased excavation sequence broadly comparable to other sites across a region.
It is very helpful for increasing the interoperability of published data to use standard terminologies for referencing different periods that are most commonly associated with the geolocation from which the site data derive. One way of doing so is to use shared terminology lists such as the Perio.do Linked Open Data (LOD) terminologies that cover an international range of periods appropriate to the geolocation of the origin of the dataset.
It’s important to note that completing the dating and periodisation of a Harris Matrix diagram can be a complex and iterative process and may require more than one version, and repeated working through, to complete the final matrix.