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This research has focused on the assessment of the compositional features and mechanical and antifouling performances of two different mortars formulated for an underwater setting, and which contain Mg(OH) as an antifouling agent. Regarding the mechanical characterization, the uniaxial compressive strength and flexural strength were measured. The composition of the materials was explored by differential thermal/thermogravimetric analysis (DTA-TG), X-ray diffraction analysis (XRPD), and scanning electronic microscopy (SEM) coupled with EDS microanalysis. The assessment of the biological colonization was evaluated with colorimetric analysis and image analysis. The results suggest that both mortars have good mechanical resistance once set underwater. Moreover, the adding of Mg(OH) improves the resistance toward biofouling; this was observed both in laboratory and sea-exposed specimens.

Thirty artefacts from the Archaeological Park of Paestum were investigated by means of scientific techniques on the occasion of the 2016 exhibition 'Possessione. Trafugamenti e falsi di antichita a Paestum'. The multi-analytic diagnostic campaign was aimed at identifying forgeries. Results provided a deeper understanding of both ancient technology and contemporary forgery techniques.

Protohistoric metal objects coming from the archaeological sites of Pontecagnano (Salerno, Italy) and Striano (Naples, Italy), preserved in the Pontecagnano National Archaeological Museum and the Paleontological Museum of Naples University “Federico II” have been studied by means of an archaeometric approach. A multi-analytical procedure including X-ray powder diffraction (XRPD), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), micro X-ray fluorescence (µ-XRF) and lead isotope ratio mass spectrometry (LIRMS), was used to characterize these objects thus providing hypotheses on the possible provenance of metallic raw materials. The investigated samples are represented by lead, silver, copper and tin bronze-based objects. Corrosion processes affecting the bronze objects were recognized as well as crusts and patinae at different stages of evolution. LIRMS analyses suggested that most of Pontecagnano artifacts were manufactured with metals from southern Tuscany, where important metal reserves were located. On the other hand, due to the limited number of samples, the provenance of the Striano objects cannot be unambiguously identified although data so far available suggest a Sardinian source.

High-precision40Ar/39Ar ages, major and trace element, and radiogenic isotope data are presented for the basanites and alkali basalts forming the southwesternmost monogenetic volcanic field in Madagascar. The volcanic rocks were erupted along fissure zones and aligned cones in a nearly flat area covered by the Cenozoic sediments of the Morondava basin. The high-precision40Ar/39Ar ages constrain the beginning of the magmatism in the Ankililoaka area to about 12 Ma, significantly earlier than suggested by previously published K/Ar ages. The Ankililoaka basanites include primitive compositions (MgO >10 wt%, Ni >200 ppm and Cr >400 ppm), whereas other basanites and alkali basalts experienced limited removal of olivine, chromiferous spinel and clinopyroxene. Initial Sr and Nd isotope ratios of the basanites are 0.70343–0.70445 and 0.51279–0.51282, respectively. The Pb isotope compositions are in the ranges206Pb/204Pb = 19.08–19.38,207Pb/204Pb = 15.61–15.64 and208Pb/204Pb = 39.1–39.4. The alkali basalts have similar87Sr/86Sr,143Nd/144Nd and207Pb/204Pb, but slightly lower206Pb/204Pb and208Pb/204Pb than the basanites. The isotopic composition of the Ankililoaka rocks partially overlaps with that of the Cenozoic volcanic mafic rocks of northern Madagascar, and differs significantly from that of the mafic volcanic rocks of central Madagascar, which have lower206Pb/204Pb and207Pb/204Pb, and higher87Sr/86Sr. Major and trace element systematics and geochemical modelling suggest that the Ankililoaka mafic alkaline rocks are low-degree melts of an incompatible element enriched peridotite source starting from depths where garnet is stable. Crustal contamination during ascent was insignificant. We argue that the genesis of the Ankililoaka alkaline magmas was triggered by melting an enriched, volatile-rich lithospheric mantle uplifted in the Cenozoic.

The file attached is the published version of the article., NHM Repository

The Ankaratra volcanic field covers an area of ~ 3800 km2 in central Madagascar and comprises of lava flows, lava domes, scoria cones, tuff rings and maars emplaced at different ages (Miocene to Recent). The volcanic products include ultramafic-mafic (olivine-leucite nephelinite, basanite, alkali basalt, hawaiite and tholeiitic basalt), intermediate (mugearite and benmoreite) and felsic rocks (trachyphonolite, quartz trachyte and rhyolite), the latter often peralkaline. The 40Ar/39Ar determinations for mafic lavas yield ages of 17.45 ± 0.12 Ma, 16.63 ± 0.08 Ma and 8.62 ± 0.09 Ma, indicating a prolonged magmatic activity. The mineralogical and geochemical variations suggest that the magmatic evolution of the alkali basalt-hawaiite-mugearite-benmoreite-trachyte series can be accounted for by removal of olivine, feldspars, clinopyroxene, Fe-Ti oxides and accessory phases, producing residual trachytic and trachyphonolitic compositions mineralogically very similar to those of other volcanic areas and tectonic settings. The Ankaratra olivine leucite nephelinites, basanites and tholeiitic basalts do not seem to be associated with significant amounts of evolved comagmatic rocks. The 87Sr/86Sr (0.70504–0.71012), 143Nd/144Nd (0.51259–0.51244) and 206Pb/204Pb (17.705–18.563) isotopic ratios of trachytes and comendite are consistent with open-system processes. However, other trachyphonolites have 143Nd/144Nd (0.51280), 206Pb/204Pb (18.648), 207Pb/204Pb (15.582) and 208Pb/204Pb (38.795) similar to those of mafic rocks, suggesting differentiation processes without appreciable interaction with crustal materials. The Ankaratra volcanism is to be directly linked to a broadly E-W-trending intracontinental extension. A large-scale thermal anomaly, associated with an anomalously hot source region, is not required to explain the Cenozoic magmatism of Madagascar.