MONITORING HYPOGEUM SYSTEMS AFFECTED BY

CRYSTALLISATIONPROCESSES AMONG CONSERVATIONNEEDS,

MICROCLIMATEFACTORSAND ACCESSIBILITY TO HERITAGE

Deodato Tapete , Barbara Mazzei , Fabio Fratini , Cristiano Riminesi , Rachele1 2 1 1

Manganelli Del Fà , Emma Cantisani , Barbara Sacchi , Oana Adriana Cuzman , Maria Gigliola1 1 1 1

Patrizi , Luciano Scaletti , Piero Tiano3 1 1

1 IstitutoperlaConservazioneelaValorizzazionedeiBeniCulturali(ICVBC),ConsiglioNazionaledelleRicerche

(CNR),ViaMadonnadelPiano10,50136,SestoFiorentino,Florence,Italy, d.tapete@icvbc.cnr.it,

deodato.tapete@gmail.com

2 PontificiaCommissionediArcheologiaSacra,ViaNapoleoneIII1,00185,Rome,Italy, bmazzei@arcsacra.va

3 Impresaindividuale,ViaCornelioCelso18,00161,Rome,Italy gigliola.patrizi@libero.it

ABSTRACT

The scientific research project HYPOGEA started in 2012 by the Pontifical Commission for Sacred

Archaeology (PCAS), Vatican, and ICVBC-CNR, Florence, aims to understand the processes of calcium

carbonate crystallisations that commonly cover the painted and rock naked surfaces in Roman catacombs,

and assess the influence exerted by the environmental conditions and their trend changes. Microclimate

monitoring of the Cubicle of the Twelve Apostles in the catacombs of Saints Mark, Marcellian and Damasus

by means of a sensor network is coupled with periodic surface pattern change detection. The latter is carried

out by combining non-invasive techniques (e.g., colorimetric measurements and digital micro-

photogrammetry) and laboratory investigations (e.g., thin and cross-section, FT-IR, XRD and ESEM

analyses) on samples taken from both ancient surfaces and newly applied frescoes. The first outcomes are

providing interesting insights into the operational issues involved in the monitoring of such unusual

environments, including for instance the choice of the parameters to take into account, as well as the

materials to use for in-situ experimentations (e.g., pigments and methods and time of application).

Monitoring is assumed here as a mean towards a long-term preservation plan, with the perspective of a

feasible balance between the aspects of conservation and those of promotion of this hypogeum painted

heritage.

Parole chiave/Key-words: Calcium carbonate crystallisation, microclimate monitoring, surface pattern

changedetection,muralpaintings,catacombs