EM Glossary


Stratigraphic Unit/Context (US/SU) = Archaeological evidence which is preserved in situ. Shape and color: rectangle with red edges and white background.

Negative Stratigraphic Unit (-US/-SU) = Action which describes a gap on a US, an evidence of an absence. Shape and color: rectangle with red edges and white background.


Structural Virtual Stratigraphic Unit (USV/s) = Reconstruction hypothesis which is proposed starting from an in situ US or a -US. Most frequently an USV/s acts as a restoration of a -US because its presence is physically "proved". Shape and color: parallelogram with blue edges and black background.

Non-Structural Virtual Stratigraphic Unit (USV/n) = Reconstruction hypothesis made starting from "sources" (such as: comparisons, general rules etc..). It is not connected to a -US and, as a result, it is not physically "proved". Usually it is connected with a USV/s or a USV/n. Shape and color: hexagon with green edges and black background.

Special Find (SF) = An "object" (fragmented or intact) out of its original context/position that can be useful for reconstruction purposes. It is a real object with several valid properties (color, material, etc ..) except the position. Shape and color: hoctagon with yellow edges and white background.

Virtual Special Find (VSF) = Virtual restoration of a SF. Shape and color: hoctagon with dark yellow edges and black background.

Seriation node (USV series) = Node that allows to manage the repetition of USV/n objects (such as: columns of a colonnade). The Seriation node acts like a proxy for the whole group of USV/n objects. Shape and color: ellipse with green contour and black background.

Continuity node = It describes the end of life of a US/USV. Shape and color: rhombus with black background and edges.

Virtual Activity (VA) = Action which is reconstruct. All necessary USVs are grouped in this action.


Extractor node = Node that can extract specific information from a source and pass them to a property.

Property node = Node that stores the information of a property useful for the reconstruction.

Source node = Textual document, multimedia content (image, video, sound), geometries etc.. from which an "extractor node" can extract information.

Combiner node = Node which combines more extractor nodes towards the same property. 


Extended Matrix Framework (EMF) = EMF includes digital solutions and software platforms useful to develop, use and share the Extended Matrix method.

Proxy Model (PM) = It is a semplified geometric representation of a stratigraphic unit which can be visualized both with an EM graph and within a 3D space.

Representation Model (RM) = It is a detailed 3D model which includes both materials and textures.

Reality Based model (RB) = It is a digital replica of an existing object or context.

Source Based model (SB) = It is a 3D model which is realized starting from sources. Within the EM methodology Proxy models and Representation models are Source Based models.


EMtools = add-on for Blender that creates a connection between the EM graph (.graphml file) and Blender.

3DSC = add-on for Blender that allows to import/export, edit, segment, create Level Of Details (LODs) of large 3D dataset (such as meshes from photogrammetric surveys) within Blender.

EMviq = 4D web-app that permits to visualize, explore, share reconstructive 3D models and 3D scenes.