Claudio Mazzoli

This contribution is part of a research project aimed at developing a methodology for the emergency stabilization of historic buildings damaged by the 2009 Abruzzo earthquake through compatible injection grouts. Several portions of multi-leaf stone masonry walls from buildings in the towns of Onna, Tempera and Sant’Eusanio Forconese, all located near L’Aquila, were selected for experimental injection tests, planned and verified by means of multiscale characterization studies. The procedure and results of the preliminary studies on the historic mortars and the grouts are here reported. The materials were characterized from the petrographic, textural, mineralogical and chemical point of view through a multianalytical approach including petrographic examinations, particle size distribution studies, XRPD analyses, bulk chemical analyses by XRF and microchemical and microstructural studies by SEM-EDS. The original mortars were subdivided in different groups and a thorough knowledge of th...

Even though the study of the pre- and protohistoric italian ceramic technology by archaeometric analysis had in the past few interest, by the time it has revealed its potential in the identification of the main technological features and in the reconstruction of exchange or trade system of the ancient communities. At the present time in the Veneto region, this approach of study regards few archaeological contexts and sometimes with small ceramic samplings. The analysis concerned both single site and some micro-regional areas (i.e. the Adige and Po plain or Garda Lake). The chronological framework of the analysed pottery (mainly using OM, XRD and XRF), published up-to-date, cover a period comprised between Early Bronze and 2nd Iron Age and regards mostly settlements (the ceramic samples from cemeteries are very few) placed on different and various geological and geomorphological conformations. The present work is intended to offer a view of the available archaeometry data in Veneto, to discriminate potential technological characteristics, to identify possible ceramic exchange and to distinguish synchronically and diachronically the modus operandi of the ancient potters in a heterogeneous geo-lithological territory. One excellent instrument of combining these different kinds of data (archaeological and archaeometric) is through the use of an “open source” Geographci Information System (GIS), whose application is here submitted.

In Cultural Heritage studies the documentation and 3D graphical representation of the artefacts is an important issue both for operative and archiving reasons. Instruments such as Laser Targeting Systems (LTS) have been continuously improved, reaching unprecedented resolution down to 1 mm, becoming standard tools for fast 3D acquisitions of vast volumes or objects with complex shapes that couldn’t otherwise be measured. Nonetheless, LTS sensitivity can be not sufficient for the study of material decay throughout time and the description of the surface morphology. In order to fill this gap, in our research we tested Structure from Motion µ-photogrammetry, a completely non-invasive technique deepening the concept of photogrammetry [1]. The method has been applied on cemetery headstones (CWGC Cemetery, Padua, Italy) made of a compact white limestone (Botticino Stone, Italy). The chosen headstones were characterized by medium decay and were not surrounded by vegetation which would have impeded a rigorous multi-view image acquisition. An APS-C Reflex camera (Nikon D-300, equipped with a 24-85mm F/2.4-4 lens) set at 50 mm focal length was used and a special holding rack has been designed in order to minimize focusing error: for a slate of about 76x38x7.6 cm, about 600 shots have been taken. SfM images were then elaborated with Photoscan software to obtain 3D models with resolution of about 25 μm (Figure 1), allowing measurement of volume loss caused by surface recession and the identification of small-scale heterogeneities which are more prone to recession. We have thus shown that this innovative technique is an ideal tool in the study of decay of carbonate rocks and in the determination of surface recession rates.

This paper presents the petrographic and textural characterization of some ornamental limestones widely used in UNESCO World Heritage sites in northeastern Italy, and the assessment of the main decay factors present in the environment where they are employed. Eleven carbonate building materials have been here considered, all commonly present in the built environment of northeastern Italy: two different varieties of Vicenza Stone (Nanto and Costozza), of Verona Stone (Red and Brown Verona), of Asiago Stone (Pink and White Asiago), and of Chiampo Stone (Ondagata and Paglierino), the Istria Stone (Orsera), the Aurisina Stone, and the Botticino Stone. The Carrara marble is also considered, and used as a reference material for the determination of the grain-size distribution. Stone durability was measured by accelerated ageing tests which reproduced freeze-thaw and salt crystallization cycles, among the main causes of deterioration in the region. Petrographic and textural features of the...

Marine biogenic skeletal production is the prevalent source of Ca-carbonate in today’s Antarctic seas. Most information, however, derives from the post-mortem legacy of calcifying organisms. Prior imagery and evaluation of Antarctic habitats hosting calcifying benthic organisms are poorly present in the literature, therefore, a Remotely Operated Vehicle survey was carried out in the Ross Sea region Marine Protected Area during the 2013–2014 austral summer. Two video surveys of the seafloor were conducted along transects between 30 and 120 m (Adelie Cove) and 230 and 260 m (Terra Nova Bay “Canyon”), respectively. We quantified the relative abundance of calcifiers vs. non-calcifiers in the macro- and mega-epibenthos. Furthermore, we considered the typology of the carbonate polymorphs represented by the skeletonized organisms. The combined evidence from the two sites reveals the widespread existence of carbonate-mixed factories in the area, with an overwhelming abundance of both low-Mg...

<p>Current global climate changes represent a threat for the stability of the polar regions and may result in cascading broad impacts. Studies conducted on permafrost in the Arctic regions indicate that these areas may store almost twice the carbon currently present in the atmosphere. Therefore, permafrost thawing may potentially cause a significant increase of greenhouse gases concentrations in the atmosphere, exponentially rising the global warming effect. Although several studies have been carried out in the Arctic regions, there is a paucity of data available from the Southern Hemisphere. The Seneca project aims to fill this gap and to provide a first degree of evaluations of gas concentrations and emissions from permafrost and/or thawed shallow strata of the Dry Valleys in Antarctica. The Taylor and Wright Dry Valleys represent one of the few Antarctic areas that are not covered by ice and therefore represent an ideal target for permafrost investigations.</p><p>Here we present the preliminary results of a multidisciplinary field expedition conducted during the Antarctic summer in the Dry Valleys, aimed to collect and analyse soil gas and water samples, to measure CO<sub>2</sub> and CH<sub>4</sub> flux exhalation, to investigate the petrological soil properties, and to acquire geoelectrical profiles. The obtained data are used to 1) derive a first total emission estimate for methane and carbon dioxide in this part of the Southern Polar Hemisphere, 2) locate the potential presence of geological discontinuities that can act as preferential gas pathways for fluids release, and 3) investigate the mechanisms of gas migration through the shallow sediments. These results represent a benchmark for measurements in these climate sensitive regions where little or no data are today available.</p>

The present archaeometric study of the Punic black-gloss ware found at the " Roman Temple " of Nora (southwestern Sardinia, Italy), dated at the end of the IV century BCE and the beginning of the II century BCE, was addressed to better define the exchanges of Punic ware, ideas and production skills within the west Mediterranean Sea. Petrographic and microstructural analyses at the scanning electron microscope (SEM) clearly indicate that the analysed pottery can be referred to two different productions, for which different base-clays were used, indicating different geological origin. On the basis of chemical composition, the black-gloss ware found at Nora can be traced back in part to the northern African area and in part to the western Sardinia coast at Tharros. None local production was identified. Moreover, on the basis of both the mineralogical composition and the microstructural features, samples produced in the northern African area and in western Sardinia definitely differ in terms of firing temperature. Therefore, on the basis of these results, a more complete scenario can be drawn on the commercial traffic active in the Western Mediterranean and in Sardinia between the end of the IV century and the first half of the II century BCE. Under a social perspective, Sardinia, thanks to its Phoenician, Punic and Italic influences, became an incubator of ideas, techniques and production knowledge that, from the interaction of the preceding cultures and their influences, gave life to many local productions, which were part of the greater phenomenon of Punic black-gloss ware in the western Mediterranean (Sardinia, Sicily, Northern Africa and the southern coasts of the Iberian Peninsula).

The distributional records of Ophiuroidea stored at the Italian National Antarctic Museum (MNA, Section of Genoa) are presented, corresponding to 1595 individuals that belong to 35 species and 17 genera. Specimens were collected in 106 different sampling stations at depths ranging from 21 to 1652 m in the framework of 14 Antarctic expeditions to the Ross Sea, one to the Antarctic Peninsula, and one to the Falkland Islands (Islas Malvinas). Three species, Amphiura joubini Koehler, 1912, Amphiura (Amphiura) angularis Lyman, 1879, and Ophiura flexibilis (Koehler, 1911), are reported as new records for the Terra Nova Bay area, whose check-list of species increases from 15 to 18 species. The determination of these three new records was based both on morphological identification and molecular analyses (COI barcoding). Some of the genetically characterised specimens were also documented through photogrammetry and micro-computed tomography and represent the first bulk of 3D models that will...

During the firing of bricks, mineralogical and textural transformations produce an artificial aggregate characterised by significant porosity. Particularly as regards pore-size distribution and the interconnection model, porosity is an important parameter to evaluate and predict the durability of bricks. The pore system is in fact the main element, which correlates building materials and their environment (especially in cases of aggressive weathering, e.g., salt crystallisation and freeze-thaw cycles) and determines their durability. Four industrial bricks with differing compositions and firing temperatures were analysed with " direct " and " indirect " techniques, traditional methods (mercury intrusion porosimetry, hydric tests, nitrogen adsorption) and new analytical approaches based on digital image reconstruction of 2D and 3D models (back-scattered electrons and computerised X-ray micro-Tomography, respectively). The comparison of results from different analytical methods in the " overlapping ranges " of porosity and the careful reconstruction of a cumulative curve, allowed overcoming their specific limitations and achieving better knowledge on the pore system of bricks.

The Euganean Hills of North East Italy have long been recognised as an area characterized by a higher than average natural radiation background. This is due to two main reasons: a) primary lithogenic radiation due to rhyolitic and trachytic outcrops, which are "acidic alkaline" magmatic rocks potentially enriched in uranium and thorium; b) secondary sources related to a geothermal field - widely exploited for spa tourism in the area since the Roman age - producing surface release of radon-enriched fluids. Though radioactivity levels in the Euganean district have been often investigated in the past - including recent works aimed at assessing the radiation doses from radon and/or total gamma radiation - no effort has been put so far into producing a thorough assessment linking radiation protection data to geological-structural features (lithology, faults, water, organic matter content, etc.). This work represents the first part of the interdisciplinary project "Geological and geochemical control on Radon occurrence and natural radioactivity in the Euganean Hills district (North-Eastern Italy)", aimed at producing detailed results of the actual radiation levels in connection mainly with lithological parameters. A detailed sampling strategy, based on lithostratigraphy, petrology and mineralogy, has been adopted. The 151 rock samples collected were analyzed by high resolution γ-ray spectrometry with ex situ HPGe detectors. Statistical and geostatistical analyses were performed, and outlier values of U and Th - possibly associated with anomalies in the geological formation - were identified. U, Th and K concentration maps were developed using both the entire database and then again after expunging the outliers; the two were then compared. In all maps the highest values can be associated to trachyte and rhyolite lithologies, and the lowest ones to sedimentary formations. The external dose due to natural radionuclides in the soil - the so called terrestrial gamma dose rate - has been calculated using the U, Th and K distribution measured in the bedrock samples.

This new dataset presents occurrence data for Porifera collected in the Ross Sea, mainly in the Terra Nova Bay area, and curated at the Italian National Antarctic Museum (MNA, section of Genoa). Specimens were collected in 331 different sampling stations at depths ranging from 17 to 1,100 meters in the framework of 17 different Italian Antarctic expeditions funded by the Italian National Antarctic Research Program (PNRA). A total of 807 specimens, belonging to 144 morphospecies (i.e., 95 taxa identified at species level and 49 classified at least at the genus level) is included in the dataset. Nearly half (45%) of the species reported here correspond to species already known for Terra Nova Bay. Out of the remaining 55% previously unknown records, under a third (~29%) were classified at the species level, while over a quarter (~26%) were ascribed to the genus level only and these would require further study. All vouchers are permanently curated at the MNA and are available for study ...

The albitized pegmatites of Vigezzo valley (Western Alps, Verbania, Italy) are renowned since the early ’70 of the last century for the findings of rare accessory minerals and of collection specimens with green, Cr-rich, beryl crystals (emeralds). The two new minerals roggianite (PASSAGLIA, 1969) and vigezzite (GRAESER et al., 1979) were first described in the Alpe Rosso pegmatite. Emerald gems, feasible to be faceted up to one carat, were found in the Pizzo Marcio northern pegmatite (BOSCARDIN et al., 1976). These pegmatites occur in the Southern root portion of the Alpine Penninic nappe and are hosted by amphibolite-grade metamorphic rocks (Fig.1). They show sensible enrichment in high field strength elements (HFSE) and they cross-cut metaperidotite-serpentinoschists interpreted as metaophiolites strips (REINHARDT, 1966). The Pizzo Marcio-Alpe Rosso albitized pegmatites belong to an extended pegmatite field several tens of kilometres in length occurring along the Insubric Line, a ...

In this study, µ-XRF was applied as a novel surface technique for quick acquisition of elemental X-ray maps of rocks, image analysis of which provides quantitative information on texture and rock-forming minerals. Bench-top µ-XRF is cost-effective, fast, and non-destructive, can be applied to both large (up to a few tens of cm) and fragile samples, and yields major and trace element analysis with good sensitivity. Here, X-ray mapping was performed with a resolution of 103.5 µm and spot size of 30 µm over sample areas of about 5×4 cm of Euganean trachyte, a volcanic porphyritic rock from the Euganean Hills (NE Italy) traditionally used in cultural heritage. The relative abundance of phenocrysts and groundmass, as well as the size and shape of the various mineral phases, were obtained from image analysis of the elemental maps. The quantified petrographic features allowed identification of various extraction sites, revealing an objective method for archaeometric provenance studies expl...

The elemental and isotopic compositions of coral exoskeletons provide valuable tools in paleoceanography. However, the chemical heterogeneities observed at micron and nanometer size scales suggest that coral physiology imprints a “vital effect” upon different structural regions, which potentially complicates and distorts their interpretations and hence paleoceanographic reconstructions. We are investigating the use of lithium and magnesium to discriminate environmental signatures from physiological effects. Li and Mg show similar geochemical behavior during elemental uptake in coral aragonite skeletons. They are highly correlated at the micron scale in shallow- and deep-sea corals, and both elements seem to be similarly affected by coral physiology. Living specimens of shallow- (Cladocora caespitosa and Porites sp.) and deep-sea (Lophelia pertusa) corals collected at different temperature-depth regimes, together with samples cultured in temperature-controlled tanks and under different CO2 conditions, have been analysed for lithium, magnesium, and calcium using laser ablation and solution ICP-MS. The Li/Ca and Mg/Ca variations at micron-resolution are large and correlate with centers of calcification versus fibrous aragonite. The Li/Ca composition of the fibrous aragonite appears to be primarily controlled by water temperature, displaying a negative correlation, although some dispersion of the Li/Ca ratios suggest a physiological influence which effects the calibration. In order to correct for this dispersion from “vital effects”, Li/Ca ratios have been normalized to Mg/Ca ratios, which show a positive and highly significant correlation with water temperatures measured in-situ. This correlation suggests that Li/Mg ratios give a clean signal that reflects the temperature. The application of Li/Mg paleothermometry thus offers a unique opportunity to more accurately reconstruct changes in temperatures at different depths in the water column.

U–Th–Pb chemical age determinations of monazite have been successfully determined using μ-PIXE at the Legnaro scanning proton microprobe facility, as well as the concentration of rare earth and other trace elements. Experimental details and the analytical procedure are described, and the results obtained are compared with data obtained using EMPA and SHRIMP II on the same analysed monazite grains, indicating that the μ-PIXE technique is an extremely powerful tool for monazite geochronology, both for the small error in the age determination, and in terms of detection limit, giving the possibility to date much younger monazite crystals than with EMPA. In addition, the high spatial resolution and the non-destructive character of this technique, potentially allows for the analysis of small monazite crystals along inclusion trails within porphyroblasts and/or present in the surrounding matrix, and to relate their age to that of the deformation in metamorphic rocks.

One of the main goals of metamorphic petrology is to obtain information on the variations of metamorphic P-T conditions during orogenesis (P-T-t paths). For this purpose petrologists are aware of the potentiality of studying reaction microstructures, although results are not always satisfactory as in most cases qualitative approaches, failing on the real meaning of specific microstructral relationships, are often adopted. Thus, the present research aimed to study the petrogenetic meaning of reaction microstructure in metamorphic rocks through the formulation of a new true three-dimensional finite-element model. For this purpose, different petrologically well studied metamorphic microstructural situations have been selected, in order to identify information, variables and constraints fundamental for the development of the model. A generalised finite-elements model (FEM) has been developed, applicable to any microstructural situation, independently on grain-size and distribution of minerals in the matrix, and able to also consider growth anisotropies, intracrystalline diffusion, pressure solution, and possibly anisotropy of the strain field. This model is based on a combination of the usual diffusion linear equations used in current irreversible thermodynamic models, providing constraints on absolute values of diffusion coefficients of chemical components, chemical potential gradients and time of reactions during metamorphism, starting from information on textural anisotropies observed in metamorphic rocks. In the model, parameterization is given by diffusion, convection and reaction coefficients of each chemical species within each finite element, which dimension is equal to the spatial resolution of the experimentally measured input data (i.e. SEM elemental maps). Thus, parameterization is able to describe locally heterogeneous reaction phenomena although based on a basically linear partial derivative differential model. Such a discretization of the continuum model is by far simpler, although slightly less efficient, than usual approaches based on adaptive discretization (adaptive FEM) and/or mechanisms of grain boundary description and localization. In a generic microstructural situation, number and tortuosity of mineral phase interfaces are so large that an explicit geometric description would be virtually unfeasible. At present, the model is under tuning using real microstructural situations observed in garnet + staurolite +/- kyanite micaschists of the Australpine Basement (Eastern Alps, Northern Italy).

ABSTRACT Cluster analysis of X-ray powder diffraction (XRPD) data was tested on datasets of ancient ceramics, to explore the possibility of using this method for automatic comparison of large numbers of samples, since the interpretation and comparison of their diffraction patterns are time-consuming processes. For this purpose, several case studies were examined, representing coarse and fine-paste pottery, materials from various regions (Italy, Syria, Iran) and of various ages (Bronze Age, Iron Age, 17th century AD). The method turned out to be suitable for defining homogeneous groups of samples for which similar raw materials/paste and firing conditions were used. This multivariate approach also allowed us to identify the most representative samples of each cluster, and was also very useful in selecting a small number of samples on which to perform detailed analyses, such as quantitative phase analysis, out of an initially large number of samples. In addition, statistical comparison of a series of firing experiments showed that cluster analysis of XRPD data is a powerful method for identifying when mineralogical changes occur and for studying the dynamics of firing in terms of mineral changes. Together with these advantages, the limitations and drawbacks of this statistical method, applied to analysis of XRPD data of ancient ceramics, were evaluated.

The archaeometric study of pottery from the settlement of Oppeano (Verona, NE Italy) indicates important changes in production technology taking place between the 10th and 5th centuries BC. Ceramic production in the Final Bronze Age was characterised by the use of grog, as in other coeval sites of the southern Adige and eastern Po plains. From the beginning of the Iron Age, the number of recipes increased considerably, the use of grog gradually decreased, and cases of importation are also attested. These changes were probably due to increasing socio-economic complexity and the introduction of new production techniques.