This study explores the interpretation of degradation and alteration phenomena as stratigraphic units, showing the preliminary results of ongoing research concerning new investigative methods and tools useful to formalize transformative processes on built heritage, in a chronological perspective. Merging conservation sciences with archaeology, the study introduces a new section of the Extended Matrix (EM) method: the Transformation Stratigraphic Unit (TSU). The aim of this work is to assess a new method for documenting and investigating cultural heritage, by generating scientifically reliable reconstructive hypotheses, and by analysing and comparing the mutual interaction of different degenerative phenomena and their relationship. The current workflow, still tentative, utilizes open-source tools and is designed to be replicable and it has been applied to the case study of the architectural complex of S. Pietro in Segni (RM). The current workflow, still tentative, utilizes open-source tools and is designed to be replicable and it has been applied to the case study of the architectural complex of S. Pietro in Segni (RM).

The archaeological remains of the Roman villa at Madonna del Piano are situated at the foot of the hill on which the municipality of Castro dei Volsci (Italy) now stands. This crucial region guarantees access to the coastal areas and is situated between the Via Latina and the Amaseno Valley. The first signs of the existence of archaeological structures can be seen in several historic aerial images, where anomalies are readily visible. The remnants of an imperial-era villa with varying periods of occupation were discovered during excavations carried out between the mid-1980s and the early 1990s. These remnants can now be identified in three distinct complexes that were previously linked as a component of a single complex. Given the site’s importance, a research project based on numerous studies and multi-scale approaches was launched in 2024 to collect new data and fill any knowledge gaps. The technique focused on the villa and its surroundings using LiDAR scans, geophysical prospections, 3D surveys of visible structures, archival research, and historical aerial photogrammetry. The findings provide new insight into the settlement by clarifying and elucidating its structure, relationships, and roles of the three complexes, and placing the results within a broader geographical context.