Frescoed wall conditions assessment with noninvasive GPR survey: The case of the Crypt of San Francesco in Irsina (Basilicata, Southern Italy)

In the field of the conservation of cultural heritage, non-invasive tests often represent the only way to monitor the conservation state of monuments and work of arts. Ground penetrating radar (GPR) plays a fundamental role in identifying and assessing the presence of failures and degradation affecting cultural heritage. This paper deals with the use of this geophysical technique to investigate some portions of deteriorated frescoed walls in the Crypt of San Francesco Church in Irsina (Basilicata, Southern Italy). Results allowed to identify several anomalies already distributed in the shallower parts of the investigated walls demonstrating unequivocally the bad conservation state of the frescoes. The GPR survey provided results in accordance with the decay and microclimate monitoring data, as derived from a previous study, and certified the needs of substantial restoration interventions.