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A series of biotic crises and turnovers have been recorded at the Norian/Rhaetian boundary (NRB), together with a putative perturbation to the global carbon cycle in the form of one or more negative carbon-isotope shifts. Despite this evidence, the full validation of Norian/Rhaetian climate changes has not been possible. In particular, no clear record of Norian/Rhaetian environmental change has yet been recovered from a terrestrial setting. The eruption of the Angayucham Large Igneous Province has been considered as a possible cause for the putative NRB negative carbon-isotope shifts. Hg as a volcanism proxy has been well-studied in many ancient marine and terrestrial sediments, but to date no Hg record has been obtained across the NRB. In this study, we focus on a terrestrial Norian-Rhaetian section (Xujiahe section) located north of Guangyuan in the northwestern Sichuan Basin, which has been correlated to the NRB using cyclostratigraphy and magnetostratigraphy. A long-lived negative trend in delta13Corg, superimposed with four negative shifts, is recognized across the NRB interval. This can be correlated to the uppermost part of the third negative delta 13Corg shift (named S3) recognized in profiles from marine sites in Europe. Contemporaneous Hg concentration, Hg/Al and Hg/TOC anomalies in the Xujiahe section were possibly caused by large-scale volcanic activity. The large amplitude changes in delta 13Corg (ca. - 5.2%o) that we observe are suggested to be associated with local wildfire and enhanced coarse sediment input, indicating a significant environmental change during the NRB interval. Similar paleoclimatic perturbations have been noted across other extinction events (e.g., end-Permian mass extinction event) as a result of the emplacement of large igneous provinces, or because of felsic volcanism.

Numerous stratiform manganese deposits occur in the Permian to Jurassic bedded chert successions of the Jurassic accretionary complexes of the Chichibu, Mino-Tamba, and North Kitakami belts in Japan. These accretionary complexes consist of deep-sea sediments accumulated in a pelagic, open-ocean setting within the Panthalassa Ocean. Although the depositional ages and processes of the Permian and Jurassic manganese deposits in these accretionary complexes have been studied, the Triassic bedded chert-hosted stratiform manganese deposits are poorly understood. We investigated the occurrence and stratigraphic distribution of Triassic stratiform manganese deposits in Japan, constraining their ages by means of integrated conodont-radiolarian biostratigraphy. On the basis of the conodont and radiolarian biostratigraphies, the depositional age of the Triassic manganese deposits was constrained to the latest Julian to earliest Tuvalian (mid-Carnian). This age indicates that the formation of the Triassic manganese deposits occurred contemporaneously with the last eruptive phase of the Wrangellia Large Igneous Province (LIP) volcanism and subsequent changes in the deep-sea redox conditions in the Panthalassa Ocean during the Carnian pluvial episode (CPE). Therefore, these manganese deposits may have been formed with the hydrothermal activity associated with the eruption of the Wrangellia LIP and/or the subsequent changes in marine redox conditions in the CPE.

The end-Triassic mass extinction (ETME) was associated with intensified deep-water anoxia in epicontinental seas and mid-depth waters, yet the absolute oxygenation state in the shallow ocean is uncharacterized. Here we report carbonate-associated iodine data from the peritidal Mount Sparagio section (Southern Italy) that documents the ETME (~ 200 Ma) in the western Tethys. We find a sharp drop in carbonate I/(Ca + Mg) ratios across the extinction horizon and persisting into the Early Jurassic. This records local dissolved oxygen and iodate decline in the near-surface ocean of low-latitude Tethys due to the development of depleted oxygen concentrations. Consequently, during the ETME even shallow-water animals, such as the megalodonts seen at Mount Sparagio, were likely the victims of oxygen-poor conditions. The shallow ocean deoxygenation coincides with the synchronous spread of deeper anoxic waters and widespread anoxic deposition on continental shelves and slopes. An upwards expansion of the mid-water oxygen minimum zone in the latest Triassic shoaled the oxycline and triggered a major marine crisis.

The addition of temper in the pottery manufacturing process is attested since Prehistoric Times and is still a production choice adopted in the ceramic industry. When the temper is composed of minerals and rocks which outcrop in regions distant from each other, new questions about the production technology arise. Such situations can be explained by considering the recycling of imported rocks, including those used for architectonic elements or sculptures, mainly coming from contemporary or earlier buildings, a practice that was widely diffused during the Roman and successive periods. This study presents evidence of the deliberate addition of recycled white marbles and sparry calcite (probably from calcareous sinters/calcite alabasters) within the long-lived production (between the 4th and 14th century CE) of coarse and cooking ware in north-eastern Italy. The petrographic analysis of about 200 potsherds attested the use of marble as unusual kind of temper, in addition to fragments of sparry calcite, in about half of the repertoire. The occurrence of different types of marbles, associated with rocks and minerals typical of the alluvial deposits of the eastern Po plain as well as locally available rocks (Euganean Hills trachyte), clearly pointed to the intentional addition of recycled marble fragments from ancient spolia, excluding the hypothesis that the pottery was imported from other regions. Detailed petrographic and microstructural analysis, including maximum grain size (MGS), accessory minerals (when observed) and grain boundary shapes allowed us to limit the provenance of these marbles to the most important Mediterranean classical source regions. These conclusions have been confirmed by the oxygen and carbon stable isotope data derived from marbles and calcite fragments mechanically separated from the ceramic paste. Some fragments of sparry calcite were characterised by very negative δ13C values, significantly different from known marble varieties, and typical of calcite crystallised in superficial geological environments, consistent with calcareous sinters, such as calcite alabasters. Moreover, a series of firing experiments were carried out in the temperature interval between 450 °C and 800 °C, both reproducing oxidising and reducing conditions, on clay pastes tempered with Carrara marble, and fired, to evaluate whether these anomalous δ13C values observed in the ancient ceramic inclusions could also be related to the firing process.

The Carnian Pluvial Episode (CPE) was a global environmental change and biotic crisis that occurred during the Carnian (Late Triassic). The climate during the CPE was characterized by a short-lived period of extreme rainfall, and an extinction of marine taxa is known to have occurred during the latest Julian (i.e. early Carnian). Although these events are considered to have been caused by the Wrangellia Flood Basalt (FB) volcanism, existing studies have found little direct evidence to support this. We investigated the temporal relationship between the eruption of Wrangellia FB and CPE using high-resolution microfossil biostratigraphy and paleo-seawater Os isotope data of an Upper Triassic bedded chert succession from an accretionary complex in Japan, which accumulated in a pelagic deep-sea environment in an equatorial region of the Panthalassa Ocean. Our biostratigraphic analysis, based on conodonts and radiolarians, and osmium isotope data show: (i) a continuous decline of initial Os isotope ratios (187Os/188Osi) in the early Julian; (ii) low 187Os/188Osi ratios during the late Julian; and (iii) an abrupt increase in 187Os/188Osi ratios at the end of the Julian. The decrease in 187Os/188Osi ratios throughout the Julian suggests an increased input of unradiogenic Os from the eruption of the Wrangellia FB into the ocean. Moreover, redox-sensitive elements, such as V and U, increased abruptly at the end of the Julian, which is the first evidence of reducing conditions during the CPE within the pelagic deep-sea Panthalassa Ocean. Marine anoxic event in the late Julian has been recognized from widespread deposition of black shales and organic-rich marls in intermediate to shallow water Tethyan sections. Thus, oxygen-depleted conditions occurred at the Tethyan shallow continental margin, as well as in the pelagic deep-sea Panthalassa Ocean, at the end of Wrangellia FB volcanism.

The Norian and Rhaetian transition (Late Triassic) is characterized by a faunal turnover in major pelagic groups, such as radiolarians, conodonts, and ammonoids. Although catastrophic events such as emplacements of large igneous provinces and/or extraterrestrial impacts have been suggested to account for this biotic turnover, firm evidence based on geochemistry of sedimentary successions is still lacking. In order to assess environmental changes across the Norian/Rhaetian boundary (NRB), we report high–resolution stratigraphic variations for whole-rock major, trace, and highly siderophile element abundances, together with Re Os isotope ratios for the Sasso di Castalda section in Lagonegro Basin, southern Italy. The section consists of a continuously exposed sequence of upper Norian (Sevatian) through the lower Rhaetian of a deep basinal deposits. Our data demonstrated that the upper Norian section records important events in stratigraphically ascending order: (1) a depositional environment moved below the Carbonate Compensation Depth, leading to the carbonate-biosilica transition associated with a slight depletion of elements favored in heavy minerals such as Zr, Hf, and Ti, (2) an input of Rochechouart impact components detected by platinum-group element anomaly, and (3) a transient change of redox state into low oxygen (dysoxic to suboxic) conditions marked by increases of V, U, and Re. This sequence of events suggests that the Rochechouart impact predates the major environmental changes resulting in faunal turnover at the NRB. Although their direct causal relationships are highly questionable given the small size of impactor and the interval between the impact horizon and the NRB, the possibility of triggering subsequent environmental and biotic collapses cannot be ruled out. This study provides the first identification of Rochechouart impact horizon in marine strata, which could be an important event marker for further studies on contemporaneous sections in the Lagonegro Basin and other localities.

A comprehensive geomorphological and structural mapping of the largest landslides in the central-eastern Southern Alps (NE Italy) is presented. Their occurrence in this Alpine sector is discussed in relation with structural geological features (bedding and faults), which are largely conditioned by the Giudicarie and Schio-Vicenza regional fault systems. Tectonic rock damaging here coexists with high relief stored energy and active deformation, which is testified by present seismicity and cumulative earthquake moment release. Based on updated rock failure ages, slope activity is concentrated at 5-3 and 1 ka, as primarily enhanced by climatic and seismic controls. The analysis of predisposing and driving factors poses the question of present and future landslide hazards for these densely inhabited Alpine valleys., Journal of Maps, 17 (3), ISSN:1744-5647

The Carnian Pluvial Episode was a phase of global climatic change and biotic turnover that occurred during the early Late Triassic. In marine sedimentary basins, the arrival of huge amounts of siliciclastic sediments, the establishment of anoxic conditions, and a sudden change of the carbonate factory on platforms marked the Carnian Pluvial Episode. The sedimentary changes are closely associated with abrupt biological turnover among marine and terrestrial groups as, for example, an extinction among ammonoids and conodonts in the ocean, and a turnover of the vertebrate fauna and the flora on land. Multiple negative carbon-isotope excursions were recorded during the Carnian Pluvial Episode in both organic matter and marine carbonates, suggesting repeated injection of 13C-depleted CO2 into the ocean–atmosphere system, but their temporal and causal links with the sedimentological and palaeontological changes are poorly understood. We here review the existing carbon-isotope records and present new data on the carbon-isotope composition of organic carbon in selected sections of the western Tethys realm that record the entire Carnian Pluvial Episode. New ammonoid, conodont and sporomorph biostratigraphic data were collected and coupled to an extensive review of the existing biostratigraphy to constrain the age of the sampled sections. The results provide biostratigraphically constrained composite organic carbon-isotope curves for the Carnian, which sheds light on the temporal and causal links between the main carbon-isotope perturbations, and the distinct environmental and biotic changes that mark the Carnian Pluvial Episode. The carbon-isotope records suggest that a series of carbon-cycle perturbations, possibly recording multiple phases of volcanic activity during the emplacement of the Wrangellia Large Igneous Province, disrupted Carnian environments and ecosystems repeatedly over a remarkably long time interval of about 1 million years.