3D model reconstruction of the chapel of Aragon and anomalies detected at about 40-50cm depth
Dr Sebastiano D’Amico, from the Department of Geosciences at the Faculty of Science, recently coordinated a project, aimed to investigate St John’s Co-Cathedral floor using non-invasive geophysical prospecting and Ground Penetrating Radar (GPR). The project was conducted in collaboration with Dr. Raffaele Persico (CNR-IBAM, Italy), Ms Cynthia De Giorgio and Adriana Alescio (St John’s Co-Cathedral Foundation) as well as a number of Academics and Researchers within the Faculty of Science (Prof. Charles Sammut, Prof. Pauline Galea, Mr. Emanuele Colica, Mr. George Bozionelos). The GPR equipment was provided by CNR-IBAM. The main goal was to identify potential burial sites and empty spaces beneath the commemorative slabs in the main nave, the side chapels and Crypt of the Grand Masters.
The main nave as well as all the lateral chapels and the Crypt of the Grand Masters have been prospected using a Ground Penetrating Radar system. Interpretation has been provided for many among the visible anomalies, most of which are mainly ascribed to burial sites. In particular, the floor of the cathedral, apart from the crypt of the Grand Masters, is composed of a large number of adjacent tombstones bearing funerary inscriptions. This mosaic is artistically important and is one of the touristic attractions of the monument. However, the GPR has revealed that the slab inscriptions are not necessarily a reflection of what lies underneath. In particular, the tombs in general do not appear to have the same size or depth, and the positions of the tombs do not necessarily coincide with those of the overlying slabs. There is no floor mosaic on the crypt of the Grand Masters and the GPR reveals only anomalies corresponding to the visible marble gravestones. Within the Co‐Cathedral in general some of the tombs may be interpreted as a vacant chamber.
A 3D model of the interior of the Cathedral and the Grand Masters crypt, incorporating the subsurface revealed by GPR, was constructed to make the result virtually available, as this allows scholars to study artefacts and sites on a much wider scale than in real life. This gives virtual access to remote objects without the limitations of museum operating hours or access rights. No special photogrammetry equipment was required. This task was carried out using an ordinary digital consumer-level camera and computer software, which is based on the latest multi-view 3D reconstruction technology already available within the Department of Geosciences.
This project aims to act as an example for future coordination among conservators, researchers, and developers who share the goals of revealing, researching, preserving, and presenting cultural heritage. This will serve as a platform for sharing knowledge and good practices, while stimulating reflections on the role of modern technologies in the preservation and promotion of cultural heritage.
The present project will be useful when considering feasibility studies for larger projects with the main goal of combining several techniques to study, restore and open public cultural heritage sites using virtual reality technology.
