GNGTS 2022 - Atti del 40° Convegno Nazionale

GNGTS 2022 Sessione 3.2 405 In this site, the excavations performed by the Soprintendenza of Catania allowed to unearth the remains of the Mother Church (Fig. 1d-e) while an accurate restoration plan reinforced the structure and recovered the remains of the chapels ornaments (Garozzo et al. , 2019). A diagnostic multidisciplinary study focusing specifically on the Mother Church building is here presented aimed at i) defining the spatial relation of the church’s structure with the 1669 lava field (Fig. 1e); ii) identifying possible hidden features inside the edifice; iii) reconstructing the historical evolution of the original building. To this end, we firstly made a drone survey to map indetail the investigatedarea; then,weuseddifferent diagnostic techniques suchas ground penetrating radar (GPR) to uncover buried crypts below paved floor, infrared thermography (IRT) and terrestrial laser scanner (TLS) to detect previous structural modifications and deformation of architectural elements caused by the push and weight of the 1669 lava flow. The 1669 Eruption. The 1669 eruption represents the largest flank eruption documented in historical times that caused the most damage to cultivated areas and settlements in the Etna region (Branca et al. , 2015). During this event, lasted four months from 11 March to 11 July, about 600 million m 3 of lava were erupted with an average effusive rate of 58±10 m 3 /s, covering an area of 40 km 2 on the southern flank of the volcano (Fig. 2a). The development of a Fig. 2 - a) The 1669 lava flow field map and location of the main settlements run over by the lava; b) view of the basalt quarry 300 m north-east of the Mother Church; c) detail of the DSM showing the typical features of lava morphology in the investigated area.