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In November 2019, the city of Venice (Italy) was hit by high tides (more than 150cm), with the highest tide peaked at 187cm. According to government statistics (reports, graphs and data of flooding since the year 1860), it is the worst flooding in Venice since 1966, when the city was hit by tides of up to 194cm (76 inches). In addition, in the last century the Venetian air quality has been strongly affected by the industrial activity in the near city of Porto Marghera and by the proximity presence of the Marco Polo Airport, which enriched the atmosphere in the CO2, SOx, NOx airborne composites. The present study addresses these issues by proposing a study of 23 brick samples collected on the main façade of the Santa Maria dei Servi Church (XIV century), one of the historical buildings hit by the high tide’s events in 2019. The façade is characterized by bricks of different color (yellow, pink and red) with an advanced decay conservation state due to the history of the monument and the environmental conditions. Color, mineralogy and texture of these samples were studied using standard methods such as, Spectrophotometry, Powder X-Ray Diffraction (PXRD), Polarized Optical Microscopy (POM) and Field Emission Scanning Electron Microscopy (FESEM-EDS). The presence of carbonates (calcite and dolomite) and new silicate phases (e.g. gehlenite and diopside) provided indications of the temperatures reached during firing and suggested the absence of a good standardization in the production process. While, X-ray diffraction and hyperspectral analysis (in the SWIR range) detected gypsum, halite and mirabilite as the main weathering products due to the salt decay process that affects monuments in Venice and in the overall lagoon environment. This work aims to increase the awareness in the decay process occurring on the historic Venetian urban texture to fix new planning tools and to achieve multiple goals oriented to a sustainable transformation of the city, leading it to more resilient solutions., Japan Geoscience Union Meeting 2022 JpGU22, May 22-27, 2022

Carbonate rocks (limestones, marbles) are among the most commonly used building materials (both as dimension and ornamental stones), and are highly vulnerable to weathering, especially in polluted areas. One of the main issues in the evaluation of cultural heritage vulnerability is the quantification of the deterioration rate. With this goal in mind, and in the frame of the HYPERION Project, the water-driven recession of stone in cultural heritage was simulated and measured in the laboratory by exposing a set of carbonate rocks, historically exploited and used in northern Italy, to accelerated ageing tests by immersion in rainwaters with different compositions. The tests were run cyclically in an environmental test chamber, alternating wetting and drying phases; at fixed intervals, the recession of each sample was quantified by bulk weight-loss measurements and surface mapping at the confocal microscope. The relationship between the different mineralogy and texture of the stones and the rate and areal development of their recession was investigated, finding that, besides water pH, calcite grain size is the most important controlling decay factor. Correction coefficients were also calculated for obtaining more reliable recession estimations from recession equations known in the literature. The findings of this study can be exploited for predicting stone deterioration in cultural heritage constrained by the relevant environmental context and the expected future climate change., SGI-SIMP 2022 Meeting, September 19-21, 2022, Torino, Italy

In this study, the recession rate of eleven carbonate stones widely used in the cultural heritage of northeastern Italy and differing in their textural features and mineralogical composition was investigated. Sam- ples of stones known as Vicenza (Nanto and Costozza varieties), Carrara marble, Verona (Red and Brown varieties), Asiago, Istria (Orsera variety), Aurisina, Chiampo (Ondagata and Paglierino varieties), and Botticino were subjected to accelerated ageing tests in an environmental test chamber for simulating the effect of rainfall, using two different water compositions corresponding to rainwater chemistry in the cities of Bologna (pH ∼7) and Stresa (pH ∼6) in Italy. Bulk stone recession was evaluated considering sample weight loss as a function of the number of wetting cycles. Moreover, direct measurements of recession were performed by confocal microscopy, which allowed 3D surface reconstruction of the stone surface and evaluation of differential recession as a function of calcite grain size. The results also allowed the definition of correction coefficients for calculating more precisely the recession rate of carbonate rocks using known recession equations from the literature. This pilot study illustrates a rapid and efficient methodological approach that can be used for providing reliable estimates of future stone deterioration in cultural heritage, related to specific environmental conditions and expected climate scenarios, which can be exploited for evaluating risk-based protection measures of a variety of historical artifacts and structures.

In many noteworthy buildings in Venice we can observe a strong loss of material at the bottom of the façades (usually in the 1-2 meters from the soil level). Capillary rise, water condensation-evaporation sub-florescence of salts can induce scaling and cracking in bricks with a subsequent reduction of the thickness of the wall section and therefore of its load-bearing capacity. This work proposes a new approach to assess the vulnerability of historical brick masonry patrimony, the most used in Venice. This new approach provides for three main steps: i) the minero-petrographic characterization of the materials (bricks and mortars); ii) the 3D photogrammetric survey and the measurements of the cross-sections of brick walls; iii) the decay assessment. For this purpose, the Church of Santa Maria dei Servi (Cannaregio, 14th century) was selected as case of study. Color, mineralogy and texture of the bricks and mortars, and secondary weathering products were studied by means spectrophotometry, X-ray diffraction, optical and scanning electron microscopy, and hyperspectral analysis. 3D surface modelling by empirical descriptions based on photogrammetry was used for understanding the effects of water and salts interaction in the bricks wall of the main façade. Results will be useful to provide previsions of long-term deterioration of that monument and they can be implemented in other brick buildings in Venice, which have the same decay pattern., AIAr Meeting, Padova, June 29 - July 2, 2022

The Torre dell’Orologio (clock tower) in Venice is an early Renaissance (1499) building in Lombard style overlooking the entrance to the Mercerie on the north side of St. Mark’s square. Its historical and artistic importance in the city as well as in the general landscape of the Italian Renaissance, is undeniable, as it is the representative expression of the architectonic stone materials most in vogue in that historical period. As part of the European project HYPERION (Horizon 2020), which is dealing with resilience and sustainable reconstruction of historical areas, the main façade of this elegant monument was mapped in order to obtain an overview of the composition of the building, its state of conservation and the history of its restoration. The mapping of deterioration morphologies was carried out following the ICOMOS-ISCS glossary of decay forms together with a quantification of the same inspired by the work of Fitzner and Heinrich (2001). To support the drafting of the maps, in-depth investigations were carried out on a series of micro-samples of both stone and deterioration products following a multi-analytical approach including petrographic and biological analyses by optical and scanning electron (SEM-EDS) microscopy, as well as through powder X-ray diffraction, ion chromatography and infrared spectrometric investigations using FTIR. The final output was the production of a series of monographic maps: one concerning the building materials, a series of maps focused on the five macro-categories of deterioration morphologies as defined in ICOMOS-ISCS (i.e. cracks and deformations, detachment, features induced by material loss, discolouration and deposit, biological colonisation). A further map was produced to graphically summarise the total state of decay of the building by reporting a Total Decay Index (TDI). In general, the most abundant and/or intense forms of deterioration detected were black crusts, patinas, discolouration and patterns related to erosion processes. The stones used in the façades are: regional (Rosso Verona and Scaglia Rossa) and extra-regional limestones as well as a series of marbles and stones already used in classical times: three crystalline marbles (Carrara and Pavonazzeto Toscano from the Apuan Alps; Proconnesian from the micro-Asiatic island of Marmara), the Rouge de Languedoc (a French limestone in Italy called Rosso di Francia), and the famous Egyptian volcanite known as Porfido rosso antico. References ICOMOS. (2008). ICOMOS-ISCS: Illustrated glossary on stone deterioration patterns. (V. Vergès-Belmin, Ed.) (XV.). Paris, France: ICOMOS. Fitzner, B., & Heinrichs, K. (2001). Damage diagnosis at stone monuments - Weathering forms, damage categories and damage indices. Acta Universitatis Carolinae, Geologica, 45(1), 12–13., AIAr Meeting, Padova, June 29 - July 2, 2022

The EU-funded project Hyperion aims at developing a “decision support system for improved resilience and sustainable reconstruction of historical areas” facing the impact of climate change and extreme weather events, with the aid of sensor-based and modeling tools. An essential part of the project involves the quantification of the current decay of cultural heritage, which may shed light on how heritage materials interact with the environment, react to microclimate stresses, and resist to future climate change in weathering models and simulations. To that purpose, a novel experimental method based on the long-term monitoring of historical building materials, their deterioration, and the relevant environmental parameters in different geographic contexts, was designed. A selection of stone and wood materials historically used in different European countries are exposed outdoors to natural weathering, in the urban environment of Italy (Padova and Venice) and Norway (Tønsberg). In every location, the same set of samples are exposed at different orientations (North, South, and horizontal plane) and their surface microclimate parameters are being monitored with temperature and moisture sensors. The microclimate data series are compared with the climate data provided by both the complementary weather stations installed in each monitoring site and the stations of the official regional agencies of environmental monitoring. At the same time, the material decay is being measured by monitoring the changes in surface topography/recession, chemical composition, and color of each building material, that is, comparing the maps acquired before and during the exposure tests by 3D optical profilometry, micro X-ray fluorescence, and colorimetry. This investigation is expected to provide a solid base for developing models of future deterioration of cultural heritage and prediction of its endurance in a changing climate., AIAr Meeting, Padova, June 29 - July 2, 2022

This contribution presents the work of research and technical development for designing a novel method for monitoring and predicting the weathering of cultural heritage, in particular of stones and timber used historically as building materials. An apparatus for long-term field tests was designed in its hardware and software components with a twofold application: Exposure of a set of selected stone and wood specimens to natural weathering, at different orientations (North, South, and horizontal plane) and environmental settings (Italy and Norway). Non-stop acquisition of microclimate data series at different resolutions, down to the scale of the specimen surface, completed by datasets of regional stations of environmental monitoring. Complementary laboratory analyses aim at setting a reference point for the state of conservation of each material before the exposure tests, and monitoring the changes of surface recession/topography (by 3D optical profilometry), thus reconstructing the relevant deterioration trends. Within the framework of the EU-funded project HYPERION, this novel experimental approach is expected to help assessing the interaction of building materials with the environment and their weathering constrained by microclimate and climate variability; combining climate model simulations, the stresses brought about by climate change can also be assessed. The findings might represent a source of precious information for the activities and decision-making protocols of the stakeholders involved in the protection of cultural heritage. Powered by, EGU22-5898; EGU General Assembly 2022, Vienna, Austria & Online, 23–27 May 2022

Climate change is one of the most critical global challenges of our time. During the last century, the anthropic activity had a great impact not only on the environment, affecting even the conservation of cultural heritage. This is becoming a mandatory issue to be tackled by international and local administrations and heritage stakeholders. Stone is one of the natural materials most utilized in historical monuments. Although stone decay phenomena have been broadly investigated in the past, only few studies are moving towards the understanding and quantification of the short- and long-term effects of climate change. This research direction, however, is essential for supporting sustainable mitigation plans and the city management. The HYPERION project aims to fill this gap, improving the knowledge of measurable material- and climate-based parameters that influence stone decay rate. The project includes simulations of future scenarios and potential effects of changing climate patterns and air quality, extreme climate events, and multi-hazard circumstances in the historical urban context. In this contribution, we present the preliminary results of the study of selected building stones used in four European demonstration sites, in Italy (Venice), Greece (Rhodes), Spain (Granada), and Norway (Tønsberg). The basic petrographic and physical-mechanical investigation of the materials is combined with accelerated ageing tests under different environmental stresses (cycles of salt crystallization and freeze-thaw and interaction with rainwaters with different compositions) and field-exposure tests. The expected results will help refining adequate material-specific models of stone surface recession and support structural and hygrothermal simulations about the future decay of cultural heritage., Japan Geoscience Union Meeting 2021 JpGU21, May 30 - June 6, 2021

This paper presents the results of an interdisciplinary archeometric study on Early Mesolithic pottery from the prehistoric site of Kabbashi Haitah, located 35 km north of Khartoum (central Sudan), along the Nile Valley. A large set of potsherds, selected after a preliminary macroscopic analysis of 1075 fragments representing the various vessels (mainly plain and globular in shape, with various rim diameter), macrofabrics and decoration types (either with or without incised or stamped decorations, i.e. incisedwavy line and rocker stamp) was analysed to define the type of the raw materials used and their manufacturing technology. The mineralogical and petrographic features, determined by optical microscopy and X-ray powder diffraction, indicate that the pottery was produced using an illitic clay tempered with quartz and/or K-feldspar derived from granite/syenite grinding, and fired in the temperature range between 750 and 900°C.