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Nowadays, tephra fallout hazard is based on coupling the physical modeling of the tephra dispersion processes with a probabilistic analysis that takes into account the natural variability of the volcanic phenomena in terms of eruption probability, eruption sizes, vent position and meteorological conditions. In this framework, we present a prototypal methodology to carry out a multi-volcano long-term tephra fallout hazard assessment in Southern Italy from the active Neapolitan volcanoes: Somma-Vesuvius, Campi Flegrei, and Ischia. FALL3D model (v.8.0) has been used to run thousands of numerical simulations (1,500 per eruption size class), considering the ECMWF ERA5 meteorological dataset over the last 30 years. The output in terms of tephra ground load has been processed within a new workflow for large-scale, high-resolution volcanic hazard assessment, in order to quantify the mean annual frequency with which the tephra load at the ground exceeds given critical thresholds at a target site within a 50-years exposure time, and the relative epistemic uncertainty. This work provides, for the first time, a multi-volcano probabilistic hazard analysis for tephra fallout, fully comparable with those used for seismic phenomena and other natural disasters in which multiple sources are integrated together, and it accounts for potential changes in regimes of each single considered volcano. This allows us to discuss also how the full information can be traced back to provide specific information about the prevalence of different volcanoes and eruptive style in the different target areas, based on hazard disaggregation. The methodology is applicable to any other volcanic areas or over different exposure times.

Tephrostratigraphic correlations commonly rely on geochemical composition supported by additional constraints (e.g., multiple stratigraphically ordered tephra, geochronological-stratigraphical constraints, and isotopic determinations), which provide key clues to restrict the number of possible candidates and disambiguate the correlation of a specific tephra among compositionally similar volcanic sources/tephra. However, such additional data may not be available or acquirable, leaving the geochemical data as sole, but challenging viable approach. In this study, two geochronologically poorly constrained late Pleistocene tephra from the eastern Adriatic –from a sand profile on Mljet Island (M-53/2) and from a marine sediment core from Pirovac Bay (PROS 721)– were correlated to known eruptions using only geochemical data (major and trace elements of glass shards), which were treated using both log ratio transformed and raw data. After the statistical treatment of the geochemical data using bivariate plots, linear discrimination analyses and selbal algorithm, the tephra M-53/2 and PROS 721 were suitably correlated with the widespread tephra generated during the Campi Flegrei eruptions of Massereia del Monte (Y-3 marine tephra, 29.0 ± 0.8 ka) and Neapolitan Yellow Tuff (14.5 ± 0.4 ka), respectively. This study showed that the correlation was hardly tenable when using the raw data, as opposed to compositional approach, which yielded satisfactory results. As a consequence, the distribution of Massereia del Monte/Y-3 tephra extended far toward the northeast, while a better chronological model, for reconstructing the paleoenvironmental changes at the Pirovac Bay location and the Holocene sea- level dynamics, could be obtained.

International audience; Glacial-interglacial variations in ice volume and sea level are essential components of the Pleistocene global climate evolution. Deciphering the timing of change of these key climate parameters with respect to the insolation forcing is central to understanding the processes controlling glacial terminations. Here we exploit the sensitivity of the Paleo Tiber River (central Italy) to sea-level forced changes in the base level and the frequent occurrence of datable tephra layers in its sedimentary successions to reconstruct the timing of the relative sea-level (RSL) change between 450 and 403 ka, i.e., across the glacial termination (T-V) that marks the transition between Marine Isotope Stage (MIS) 12 and MIS 11. The analysis hinges on new stratigraphic data, tephra geochemical fingerprinting, and 40Ar/39Ar dating from a fluvial section that represents the inland counterpart of the near mouth, coastal aggradational successions of the San Paolo Formation (SPF). Tephra correlation indicates that the morpho-stratigraphic record of the inland section is as sensitive to the sea-level change as its coastal counterparts, which makes it ideal to complement previous RSL reconstructions from the Tiber River catchment basin, thereby providing a more detailed picture of the sea-level history across T-V. Combined sedimentological and morphological proxies of the composed inland-coastal SPF record document the occurrence of two phases of relatively rapid sea-level rise, here interpreted as meltwater pulse (MWP) events. The earlier MWP occurred between ∼450 and ∼445 ka and matches a relatively minor episode of the sea-level rise documented in an existing RSL record, while the younger MWP at ∼430 ka corresponds to the high amplitude sea-level rise that marks T-V. We find that both MWPs coincide with episodes of ice-rafted debris deposition in the North Atlantic (Heinrich-like events) and with attendant Southern Hemisphere warming, plausibly associated with the bipolar seesaw.

The timing, duration and evolution of sea level during the Marine Isotope Stage 5e (MIS 5e) highstand is a subject of intense debate. A major problem in resolving this debate is the difficulty of chronologically constraining the sea level fall that followed the peak of the highstand. This was mainly controlled by ice-sheet dynamics, the understanding of which is relevant for assessing future sea-level behavior due to global warming. Here we use stratigraphical and geochoronological (U/Th dating and tephra fingerprinting) evidence from the Infreschi archaeological cave (Marina di Camerota, Southern Italy) to constrain relative sea level (RSL) evolution during the MIS 5e highstand and younger stages. Uranium-thorium dating of speleothem deposition phases places the maximum highstand RSL at 8.90 ± 0.6m a.s.l., as indicated by the near-horizontal upper limit of Lithophaga boreholes measured for along a ∼3.5 km coastal cliff section. Geochronological data show that RSL fell more than 6 m before ∼120 ka, suggesting a duration of the Last Interglacial highstand significantly shorter than proposed in some previous studies. Modelling shows that the RSL trend predicted by the ICE-5G and ICE-6G ice-sheet simulations is consistent with our data, but requires an additional significant reduction of both Greenland and Antarctic ice sheets to match the height of the local maximum highstand if no correction for tectonics is applied. Reconciling field data and models requires an earlier and likely shorter duration of the MIS 5e highstand. This suggests that our new data can constrain global ice-volume variations during the penultimate deglaciation, as well as glacial inception at the end of the Last Interglacial. According to our chronology, there is no local evidence of higher-than-present-day sea levels after 120 ka.

Through a systematic integrated approach, which combined lithostratigraphic, geochronological and geochemical analyses of tephra from near-source sections of the peri-Tyrrhenian volcanoes and mid to distal settings, here we provide an improved tephrochronological framework for the Marine Isotope Stage 11c interglacial (MIS 11c, ∼425–395 ka) in the Central Mediterranean area. Specifically, we present the complete geochemical dataset and new high-precision 40Ar/39Ar ages of the previously poorly characterized earliest pyroclastic products of the Vico volcano (420–400 ka), including the Plinian eruptions of Vico α and Vico β and the immediately post-dating lower magnitude explosive events. Furthermore, we also provide new geochronological and geochemical data for the distal tephra layers preserved in the aggradational succession of the Tiber delta (San Paolo Formation), Roman area, which records sea level rise relating to the MIS 12 (glacial) to MIS 11 (interglacial) transition. Five pyroclastic units were recognized in Vico volcanic area, four out of which, Vico α, Vico β, Vico βtop (a minor eruption immediately following Vico β and temporally very close to it) and Vico δ were directly dated at 414.8 ± 2.2 ka, 406.5 ± 2.4 ka, 406.4 ± 2.0 ka and 399.7 ± 3.2 ka respectively (2σ analytical uncertainties). These new data allow a critical reappraisal of the previously claimed identifications of Vico tephra from mid-distal to ultra-distal successions (i.e., Vico-Sabatini volcanic districts, Roman San Paolo Formation and Castel di Guido archaeological site, Sulmona Basin, Valdarno and Lake Ohrid), which were unavoidably biased by the poor and incomplete geochemical and geochronological reference datasets previously available. Such an improvement of the tephrochronological framework brings great benefits to any future investigations (e.g., paleoclimatology, archaeology, active tectonic, volcanology) in the dispersal areas of the studied eruptions at the key point in time that is MIS 11.

RATIONALE: The suitability of organic matter (OM) removal pre-treatments in isotopic studies of lacustrine carbonates is currently under debate. Naturally occurring OM seems to have a negligible effect on the bulk isotopic composition of carbonates compared with changes induced by pre-treatments. This study provides further insights into the possible effects induced by commonly used pre-treatments on natural lacustrine carbonates. METHODS: Sixteen samples from the Fucino F1-F3 lacustrine succession (Abruzzo, central Italy) were characterised for their mineralogical and geochemical composition and each was split into three identical aliquots. One aliquot was left untreated while the remaining two were treated with NaOCl and H2 O2 dilutions. The same treatment was applied to an internal standard consisting of pure Carrara marble. The treated and untreated samples were analysed for their carbon (δ13 C values) and oxygen (δ18 O values) isotope compositions using an Analytical Precision AP2003 isotope ratio mass spectrometer. RESULTS: The samples had variable proportions of endogenic and detrital components, the detrital portion being more (less) abundant during colder (warmer) climate phases. We observed that neither the NaOCl nor the H2 O2 treatment was able to completely remove OM and therefore there was selective removal of compounds within the OM pool. A possible effect of pre-treatment is the loss of carbonates intimately interspersed within the OM, as suggested by the evolution of isotopic ratios towards the local detrital array. CONCLUSIONS: Our study highlights sample-specific changes in geochemistry associated with sample pre-treatments; however, such changes do not seem to lead to either systematic and/or predictable isotopic shifts. We suggest that the suitability of NaOCl or H2 O2 pre-treatments for OM removal should be evaluated on a case-by-case basis. In the specific case of lacustrine marls from palaeo-lake Fucino containing relatively low amounts of OM and in which both detrital and endogenic carbonates occur, both pre-treatments should be avoided.

The Late Quaternary benthic foraminiferal and ostracod assemblages from two continuous cores drilled in the Port of Salerno were studied to define their relationship with geochemical characteristics of the sediments and with the palaeoenvironmental evolution. The succession, ranging from Late Pleistocene to the 20th century, recorded the transition from a marine coastal environment under natural conditions to a depositional context affected by anthropogenic influence. In the lower part of the sequence, ecological and sedimentary changes were linked to sea-level changes due to Late Quaternary climatic phases, as well as to volcanic events such as the Campanian Ignimbrite eruption, represented by levels with high metal (Fe, Mn, Pb, Zn) concentrations, possibly leading to low pH phases. Later human activities, such as the construction of harbour facilities in the 18th century and the industrial development in the 19th century, influenced environmental variations, as shown in the upper part of the succession. High levels of heavy metal concentrations (Co, Cu, Fe, Pb, V) recorded in layers deposited in the 1800s suggest the presence of a pollution event which could be linked to manufacturing activities and might have occurred during the first part of the 19th century. Calcareous meiofaunal assemblages showed high diversity values, probably due to the occurrence of ”rare short lived” species in an unstable environment. Assemblages were dominated by the foraminiferal species Ammonia aberdoveyensis and Haynesina depressula, and by the ostracods Pontocythere turbida and Semicytherura sulcata, which are considered as possibly stress-tolerant species.

A multidiplisciplinary study, including geomorphological, lithostratigraphical, geochronological, geochemical, and paleontological investigations, was carried out in the coastal area of Salerno city, southern Italy. The study aimed to outline the Late Glacial-Holocene geoenvironmental evolution of Salerno's port area in response to both natural and anthropogenic factors. The geomorphological study included an examination of historic maps, which enabled a detailed reconstruction of the coastal landscape change during historic times. Lithostratigraphical analyses of three new boreholes, supported by radiocarbon and tephrochronological data, and of previously retrieved core-successions and archaeological trenches, extends our reconstruction of the paleogeographical evolution of the Salerno coastal area back to the Late Pleistocene. Geochemical and paleontological analyses of samples from the newly acquired cores were combined with the lithofacies analyses of previously retrieved cores to detect ancient harbors in the area of the current port facilities of the city and surrounding urban areas. This work contributes to scientific debate about the specific sedimentary architectures and geochemical properties of the Salerno harbor environment and refines methodological approaches for characterizing and assessing the evolution and demise of ancient port facilities in Mediterranean coastal cities.

Here we present the first tephrostratigraphic, palaeomagnetic, and multiproxy data from a new ∼98 m-deep sediment core retrieved from the Fucino Basin, central Italy, spanning the last ∼430 kyr. Palaeoenvironmental proxy data (Ca-XRF, gamma ray and magnetic susceptibility) show a cyclical variability related to interglacial-glacial cycles since the Marine Isotope Stage (MIS) 12-MIS 11 transition. More than 130 tephra layers are visible to the naked eye, 11 of which were analysed (glass-WDS) and successfully correlated to known eruptions and/or other equivalent tephra. In addition to tephra already recognised in the previously investigated cores spanning the last 190 kyr, we identified for the first time tephra from the eruptions of: Tufo Giallo di Sacrofano, Sabatini (288.0 ± 2.0 ka); Villa Senni, Colli Albani (367.5 ± 1.6 ka); Pozzolane Nere and its precursor, Colli Albani (405.0 ± 2.0 ka, and 407.1 ± 4.2 ka, respectively) and Castel Broco, Vulsini (419–490 ka). The latter occurs at the bottom of the core and has been 40Ar/39Ar dated at 424.3 ± 3.2 ka, thus providing a robust chronological constrain for both the eruption itself and the base of the investigated succession. Direct 40Ar/39Ar dating and tephra geochemical fingerprinting provide a preliminary radioisotopic-based chronological framework for the MIS 11-MIS 7 interval, which represent a foundation for the forthcoming multiproxy studies and for investigating the remaining ∼110 tephra layers that are recorded within this interval. Such future developments will contribute towards an improved MIS 11-MIS 7 Mediterranean tephrostratigraphy, which is still poorly explored and exploited.

Mediterranean climates are characterized by strong seasonal contrasts between dry summers and wet winters. Changes in winter rainfall are critical for regional socioeconomic development, but are difficult to simulate accurately1 and reconstruct on Quaternary timescales. This is partly because regional hydroclimate records that cover multiple glacial–interglacial cycles2,3 with different orbital geometries, global ice volume and atmospheric greenhouse gas concentrations are scarce. Moreover, the underlying mechanisms of change and their persistence remain unexplored. Here we show that, over the past 1.36 million years, wet winters in the northcentral Mediterranean tend to occur with high contrasts in local, seasonal insolation and a vigorous African summer monsoon. Our proxy time series from Lake Ohrid on the Balkan Peninsula, together with a 784,000-year transient climate model hindcast, suggest that increased sea surface temperatures amplify local cyclone development and refuel North Atlantic low-pressure systems that enter the Mediterranean during phases of low continental ice volume and high concentrations of atmospheric greenhouse gases. A comparison with modern reanalysis data shows that current drivers of the amount of rainfall in the Mediterranean share some similarities to those that drive the reconstructed increases in precipitation. Our data cover multiple insolation maxima and are therefore an important benchmark for testing climate model performance.

Proxy records of past climate change spanning beyond the radiocarbon range commonly derive their chronologies from orbital tuning strategies, thus bounding our spatio-temporal reconstructions to a priori assumptions that can not be directly tested. Here we present a tephrochronologically constrained framework of past environmental and climatic changes in the central Mediterranean region during the last ca. 190 ka. Our research is based on a high-resolution, multi-proxy study of a sedimentary record (cores F1-F3) retrieved from the Fucino Basin lacustrine succession, central Italy, in 2015. We update the existing tephrostratigraphic framework of the F1-F3 record with the finding of the widespread Campanian Ignimbrite tephra marker layer and produce a robust and independent chronology based on new and published 40Ar/39Ar and 14C dating of 17 tephra layers. Observed palaeoenvironmental changes are tracked in other lacustrine, marine and speleothem records across the Mediterranean and North Atlantic regions via tephrostratigraphic correlations and chronological matching providing a robust assessment of age uncertainties. Results show a complex interplay between local environmental changes and broad-scale climatic processes highlighting a strong orbital forcing on glacial-interglacial changes. Along with these major changes we detect prominent millennial-scale variability. During times of intermediate global ice volumes, Mediterranean mountain ecosystems oscillated around an “interglacial” state suggesting that climatic shifts, although large, did not exceed the local environmental tolerance-resilience threshold. Conversely, during periods of large global ice volume, we observe subdued millennial-scale variability with ecosystems operating in a strictly ruled glacial environment.

International audience; Among past interglacial periods, Marine Isotope Stage (MIS) 19 is particularly interesting because its orbital geometry is very similar to that of the present interglacial. Here we present a high-resolution (sub-centennial) multiproxy record covering the ca. 790-770 ka interval, i.e. the interglacial MIS 19c and the ensuing glacial inception of MIS 19b, from a lacustrine sediment sequence retrieved from the Sulmona Basin (central Italy). The record has an independent chronology based on radiometric dating of six volcanic ash layers, and the resulting age model has a mean associated uncertainty of ±2.6 kyr. Variations in sediment geochemistry and mineralogy are interpreted in terms of past hydrological and temperature changes. Several millennial and sub-millennial events of reduced precipitation are well expressed. Comparisons with continental and marine records from the mid-latitude and sub-polar North Atlantic suggest a broad spatial expression for the observed events. Events occurring within the interglacial are not clearly associated with changes in marine proxies in the Iberian Margin, although similarities with the record from the sub-polar North Atlantic can be recognized and tentatively linked to changes in local hydrography having a downstream effect amplified by changes in atmospheric circulation. During the glacial inception, changes in the Sulmona record are coherent with changes in North Atlantic records, with drier events likely associated with meltwater-induced intervals of AMOC weakening. An event at ca. 785.6 ka may also reflect oceanic changes caused by freshwater discharges from residual ice-sheets and an outburst flood, similar to the 8.2 ka event in the Holocene.

The Sabatini Volcanic District (SVD), active between 0.8 and 0.07 Ma, is a volcanic field in the Roman province (Central Italy) located along the Tyrrhenian margin of the Italian peninsula. In this volcanic region, high-K magmas originated from a metasomatised phlogopite-bearing peridotite mantle recording subduction-related fluids and/or melting processes. Here, we investigate magma evolution during the six main eruptive phases of the SVD by means of chemical and isotopic (Sr and Nd) analyses. Specifically, we analyzed clinopyroxene crystals from juvenile pumice and scoria clasts and lavas, from 40 major SVD eruptive units chronologically well constrained by 40Ar/39Ar dating. 87Sr/86Sr and 144Nd/143Nd ratios in SVD clinopyroxene range 0.7095–0.7115 and 0.51210-0.51214, respectively. The mean Sr and Nd isotope compositions of each eruptive phases show a gradual, long-term decrease over the entire SVD eruptive history. However, when considering the distinct temporal windows of the individual eruptive phases, a significant variability of the Sr-Nd isotope ratios emerges, thus highlighting a more complex, time-dependent geochemical trend for the erupted magmas, with respect to a previously described trend at the nearby Colli Albani Volcanic District (0.6–0.04 Ma). Geochemical features of clinopyroxene in lavas and juvenile pyroclasts suggest that magma differentiation occurred in an open system due to assimilation of siliciclastic sedimentary rocks. Moreover, a critical review of the available geochemical data, in light of 40Ar/39Ar ages, allows the recognition of the SVD as the source of widespread tephra markers recorded in the central Mediterranean area by previous works.

The Matuyama-Brunhes Boundary (MBB) recorded in the lacustrine sequence in the Sulmona basin (central Apennines, Italy) raised considerable scientific interest and has been the focus of various papers (Giaccio et al. 2013; Sagnotti et al. 2014; 2016). The interest comes from evidence for a very sharp geomagnetic polarity transition, that is radioisotopically dated. A paper recently published by Evans and Muxworthy (2018) questions the reliability of the Sulmona palaeomagnetic record. With new measurements on companion samples from the same stratigraphic block studied by Evans and Muxworthy, we show that directional results obtained by different demagnetization treatments (AF, thermal and thermal + AF) are in close agreement. We here propose a different interpretation of the magnetostratigraphy, and confirm that the palaeomagnetic record of the MBB geomagnetic reversal in the Sulmona basin is properly documented

Lake Ohrid, located in the Central Mediterranean region downwind of the Italian volcanoes, has great potential for developing a detailed record of the explosive activity of these volcanoes. Electron microprobe and Laser Ablation Inductively Coupled Plasma Mass Spectrometry geochemical analyses of juvenile glass fragments of previously not analysed tephra layers of the DEEP site sediment record of Lake Ohrid expand the existing tephrostratigraphy for the interval Marine Isotope Stages 1–16. The geochemical signatures of all tephra layers suggest an origin exclusively from the Italian volcanism. Eight of these tephra layers have potential equivalents in marine and terrestrial archives of the Central Mediterranean region (OH-DP-1966/SC5/A7; OH-DP-1955/CES1/A2; OH-DP-1055/S1; OH-DP-1006/S2; OH-DP-0997/S3, OH-DP-0710/S8/C-51; OH-DP-0766/ODP5/P-13; OH-DP-0505/ODP4). Nine tephra layers, which have not been described so far, help to reconstruct the late volcanic activity of Mount Vulture (OH-DP-2439) and the Paleovulsini (OH-DP-1998), the pre- and post Rio Rava activity of the Roccamonfina volcano (OH-DP-1911/-1812/-1733/-1640/-1527), the early activity of the Aeolian Arc (OH-DP-1513/-1520), and the Bracciano activity of the Monti Sabatini volcanic district (OH-DP-1175). The multi-proxy dataset and chronology of the DEEP site sediments allowed definition of the climatostratigraphic position for all tephra layers and constrain the ages of so far unknown and/or undated tephra layers. The presented data provide a crucial increase of knowledge of the Middle Pleistocene tephrostratigraphy in the Central Mediterranean back to 630 ka and allows new insights of the volcanic activity of Roccamonfina, the Roman Province, the Campanian Volcanic Zone (CVZ), the Aeolian Arc, Pantelleria, and Mount Vulture.

The Grotta del Cavallo contains one of the most important stratification of Mousterian, Uluzzian and Final Epigravettian tecnocomplexes; its chronology is of paramount importance for understanding the timing of the transition between Middle and Upper Palaeolithic in the Mediterranean region as well as the demise of the Neanderthal and the dispersal of the first anatomically modern humans through Europe. Within the stratigraphy of the cave three different volcanic ash layers occur (layer G, Fa and C-II). They are located in the middle section of the Mousterian (layer G), in between the Mousterian and Uluzzian layers (layer Fa) and on top of the Uluzzian horizons (layer C-II). The three tephra layers were chemically fingerprinted and correlated to well-known and precisely dated widespread Late Pleistocene tephra markers. Specifically, layer G, Fa and C-II were correlated to the X-6 (108.7 ± 0.9 ka), Y-6 (45.5 ± 1.0 ka) and Campanian Ignimbrite (39.85 ± 0.14 ka), respectively. These findings provide robust chronological points allowing to conclude that: (i) the Mousterian occupation of the cave took place after the fall of the sea level following the MIS 5e high-stand; (ii) the Mousterian-Uluzzian boundary can be dated to 45.5 ± 1.0 ka and climatostratigraphically firmly placed at the transition between the Greenland Interstadial 12 (GI12)-Greenland Stadial 12 (GS12); (iii) the Uluzzian lasted for at least five millennial spanning the GS12-GI9 period and ended at beginning of the Heinrich Event 4.

Trace element compositions determined by ICP-MS have been acquired for six eruptive units from the most recent explosive activity of the Colli Albani Volcanic District, central Italy, documented at the Albano maar by seven eruptive units dated at ~ 69 ka (Albano 1–3) and ~ 41 ka through ~ 36 ka (Albano 4–7). Ratios of selected immobile trace elements (e.g. Zr/Y vs Nb/Y) have been used to build an original reference dataset of 15 samples for discriminating the six main units of the Albano maar eruptive succession, albeit it has to be considered preliminary since scarcity of outcrops and incomplete occurrence of these eruptive units hindered the acquisition of a larger dataset. In order to test its applicability, we have used it as an integrative tool to identify a weathered tephra layer (CIS-1) which has been here dated by 40 Ar/ 39 Ar method at 70 ± 2 ka, previously attributed to an undefined Albano unit, occurring in the stratified Paleolithic site of Cava Muracci. The new 40 Ar/ 39 Ar and trace element data, alongside the previous major element composition, indicate that tephra CIS-1 correlates with Albano 3 (~ 69 ka). The results of this study, besides providing a chronological constraint for a local archaeological site, demonstrate how trace element discrimination diagrams combined with other tephrochronological constraints can provide a useful indication for tephrostratigraphic purposes. Although more reference data are needed to test the full soundness of the trace element ratios for fingerprinting individual Albano units, the results also support this method as a new promising tool for the development and application of the tephrochronology, which would offer the great advantage to be potentially applied even to strongly altered and unsuitable volcanic deposits.

The Late Pleistocene Campanian Ignimbrite (CI) super-eruption (Southern Italy) is the largest known volcanic event in the Mediterranean area. The CI tephra is widely dispersed through western Eurasia and occurs in close stratigraphic association with significant palaeoclimatic and Palaeolithic cultural events. Here we present new high-precision 14C (34.29 ± 0.09 14C kyr BP, 1σ) and 40Ar/39Ar (39.85 ± 0.14 ka, 95% confidence level) dating results for the age of the CI eruption, which substantially improve upon or augment previous age determinations and permit fuller exploitation of the chronological potential of the CI tephra marker. These results provide a robust pair of 14C and 40Ar/39Ar ages for refining both the radiocarbon calibration curve and the Late Pleistocene time-scale at ca. 40 ka. In addition, these new age constraints provide compelling chronological evidence for the significance of the combined influence of the CI eruption and Heinrich Event 4 on European climate and potentially evolutionary processes of the Early Upper Palaeolithic.

An integrated investigation including geological, geomorphological, geophysical and structural survey, tephra analyses, 14C and 40Ar/39Ar dating, as well as paleoseismic trenching along the N-Matese fault system is presented. The study allowed the characterization of the tectonic mobility of this structure as well as the associated Bojano basin sedimentary-tectonic evolution since the early Middle Pleistocene, providing also new clues concerning the fault historical activity and the associated Mw > 6.5 earthquakes. We have found lines of evidence for > 1 mm/yr slip rate along the presently buried Bojano fault during the mid Middle Pleistocene, and similar rates for the main fault segments paralleling the Matese flanks. The buried Bojano fault significantly slowed down during the last 300 kyr, ceasing its activity before the Holocene. In turn, the segments outcropping along the Matese flanks reactivated at the onset of Late Pleistocene, after a long period of quiescence (480–110 ka), with robust slip rates that would seem even accelerating in post LGM times. Paleoseismic data suggest the occurrence of four Mw > 6.6 earthquakes in the past 3 ka, three of which match the little known 280 BC event, and the devastating 1456 and 1805 earthquakes. © 2017 Elsevier B.V.

A review of the existing data for the Middle Pleistocene glacial remnants in the Apennines and new stratigraphic and tephrochronological data has enabled us to recognize at least five glacial stages during Marine Isotope Stages 14, 12, 10, 8 and 6. In particular, the identification of deposits attributable to Marine Isotope Stage 12 has filled a gap that was hitherto difficult to justify because, in the Mediterranean area, this glacial period is characterized by significant climatic changes that are connected with major environmental changes and glacial stages in the neighbouring Balkans and in Greece. The association between the Middle Pleistocene moraines and closed karst-tectonic basins, which are related to faults active in post-glacial times, suggests that tectonics has played a leading role in accommodating sediment deposition and thus in preserving the sedimentary record of these glaciations. Tectonic activity has, in some places, significantly influenced the altitude of the glacial cirques and the terminal moraines so that assessment of the equilibrium-line altitude based on these data is unreliable.

Palynology of fossil faeces is still extremely rare and its contribution to the interpretation of the environment undervalued. In this paper we present the results of pollen analysis performed on cave hyena coprolites [Crocuta crocuta spelaea (Goldfuss, 1832)] from Marine Isotope Stage 3 (MIS 3) sites of Cava Muracci (Cisterna di Latina, central Italy) and Tana delle Iene (Ceglie Messapica, southern Italy). This study provides new insights into the vegetation of the Late Pleistocene of peninsular Italy, until now known only through long pollen records. It also shows how the content of coprolites, combined with faunal data and geochronological investigations, can represent a potential integrative source of palaeoclimatic proxy data. Our results indicate that the surroundings of both of the hyena dens were characterised by a patchy landscape with open lowlands dominated by steppe and grassland vegetation, while a few mesophilous and thermophilous trees were present in more humid areas, probably along the marine coast and inland. The harsh glacial climate appears to have been milder at Cava Muracci than at Tana delle Iene. This could be due either to the different environmental features of the two sites or to the high climatic variability that occurred during MIS3.

Made available in DSpace on 2018-11-26T15:28:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-01 A recent study of the Matuyama-Brunhes (M-B) geomagnetic field reversal recorded in exposed lacustrine sediments from the Sulmona Basin (Italy) provided a continuous, high-resolution record indicating that the reversal of the field direction at the terminus of the M-B boundary (MBB) occurred in less than a century, about 786 ka ago. In the sediment, thin (4-6 cm) remagnetized horizons were recognized above two distinct tephra layers-SUL2-19 and SUL2-20-that occur similar to 25 and similar to 35 cm below the MBB, respectively. Also, a faint, millimetre-thick tephra (SUL2-18) occurs 2-3 cm above the MBB. With the aim of improving the temporal resolution of the previous Sulmona MBB record and understanding the possible influence of cryptotephra on the M-B record in the Sulmona Basin, we performed more detailed sampling and analyses of overlapping standard and smaller samples from a 50 cm-long block that spans the MBB. The new data indicate that (i) the MBB is even sharper than previously reported and occurs similar to 2.5 cm below tephra SUL2-18, in agreement with the previous study; (ii) the MBB coincides with the rise of an intensity peak of the natural remanent magnetization (NRM) intensity, which extends across SUL2-18; (iii) except for a 2-cm-thick interval just above tephra SUL2-18, the rock magnetic parameters (k, ARM, M-r, M-s, B-c, B-cr) indicate exactly the same magnetic mineralogy throughout the sampled sequence. We conclude that either SUL2-18 resulted in the remagnetization of an interval of about 6 cm (i.e. during the NRM intensity peak spanning similar to 260 +/- 110 yr, according to the estimated local sedimentation rate), and thus the detailed MBB record is lost because it is overprinted, or the MBB is well recorded, occurred abruptly about 2.5 cm below SUL2-18 and lasted less than 13 +/- 6 yr. Both hypotheses challenge our understanding of the geomagnetic field behaviour during a polarity transition and/or of the NRM acquisition process in the Sulmona lacustrine sediment. Ist Nazl Geofis & Vulcanol, I-00143 Rome, Italy CNR, Ist Geol Ambientale & Geoingn, I-00015 Monterotondo, Rome, Italy Columbia Univ, Barnard Coll, New York, NY 10027 USA CEA CNRS UVSQ, IPSL, UMR8212, Lab Sci Climat & Environm, F-91190 Gif Sur Yvette, France Univ Paris Saclay, F-91190 Gif Sur Yvette, France Berkeley Geochronol Ctr, Berkeley, CA 94709 USA Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA 94709 USA Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, BR-13506900 Rio Claro, SP, Brazil

A multi-proxy record was acquired from a Late Pleistocene lacustrine succession in the Sulmona basin, central Italy. Previous and new tephrostratigraphic analyses of six volcanic ash layers constrain the investigated interval to between 92.3 and 115.0 ka. The d18O composition is interpreted as a proxy for precipitation amount in the high-altitude catchment of the karst recharge system. The oxygen record shows millennial variability that is consistent with Greenland Interstadials GI25-GI23 and North Atlantic cold events C24-C22, indicating a strong Mediterranean-North Atlantic climate teleconnection. However, while no appreciable isotopic difference between the three interstadials is revealed by the Greenland record, the Sulmona section reveals a wetter climate during GI24 compared with GI23 and GI25. Comparison of our record with speleothem and pollen data from central and southern Italy suggests higher seasonality of the precipitation (wet winter-dry summer) for GI24, which matches a precession minimum. The wettest period recorded at Sulmona is also coincident with the deposition of Sapropel S4 in the Tyrrhenian Sea, suggesting a teleconnection between a higher seasonality in the western Mediterranean and strengthening of the boreal monsoon system.

The 23 km long Sulmona normal fault flanks the southwestern slope of the Mount Morrone range in the central Apennines. To date, the recent activity of this structure is uncertain, as the faulting evidence concerns only undated deposits and the fault cannot be associated with any of the strong historical earthquakes ( M w >6.5) of the region. Our observation from ∼1 Ma offset slope breccias, coupled with new tephrochronological data on faulted early Last Glacial lacustrine infilling of the Sulmona basin, implies a vertical slip rate of ∼0.5 mm/yr over both the long term and middle term. Moreover, at the apex of a Late Pleistocene alluvial fan, radiocarbon dating of offset stratigraphy uncovered in four paleoseismological trenches shows that repeated earthquakes resulted in more than 4 m of vertical offset since ∼9 ka, providing again a minimum Holocene vertical slip rate of ∼0.5 mm/yr. In combination with the results of the trench exposure, we define four faulting events in the past ∼9 ky B.P., and at least one before then. The most recent is constrained by robust radiocarbon dates as the middle of the second century A.D. The penultimate event was around the middle of the fifth millennium B.P., whereas the other two events are dated in a time between 8.5 ky to 6.5 ky B.P. and around 9 ky cal B.P. The oldest occurred before 9.5 ky B.P. As well as revealing the unexpected paleoseismic history of the Sulmona silent fault, our data provide a recurrence time for M w ≥6.5 earthquakes of ∼2.4 ky versus an elapsed time of ∼1.85 ky since the last event. The latter matches with an earthquake previously hypothesized through archaeoseismic clues collected from several Roman settlements of the Sulmona Plain, all of which were dated to halfway through the second century A.D. Online Material: Table of major‐element compositions, field photos, and Harker diagrams.

The DEEP site sediment sequence obtained during the ICDP SCOPSCO project at Lake Ohrid was dated using tephrostratigraphic information, cyclostratigraphy, and orbital tuning through marine isotope record. Although this approach is suitable for the generation of a general chronological framework of the long succession, it is insufficient to resolve more detailed paleoclimatological questions, such as leads and lags of climate events between marine and terrestrial records or between different regions. In this paper, we demonstrate how the use of different tie points can affect cyclostratigraphy and orbital tuning for the period between ca. 140 and 70 ka and how the results can be correlated with directly/indirectly radiometrically-dated Mediterranean marine and continental proxy records. The alternative age model obtained shows consistent differences with that proposed by Francke et al. (2015) for the same interval, in particular at the level of the MIS6-5e transition. According to this age model, different proxies from the DEEP site sediment record support an increase of temperatures between glacial to interglacial conditions, which is almost synchronous with a rapid increase in sea surface temperature observed in the western Mediterranean. The results show how important a detailed study of independent chronological tie points is for synchronizing different records and to highlight asynchronisms of climate events.

Gamma ray (GR) fluctuations and potassium (K) values from downhole logging data obtained in the sediments of Lake Ohrid from 0 to 240 m below lake floor (b.l.f). correlate with fluctuations in δ18O values from the global benthic isotope stack LR04 (Lisiecki and Raymo, 2005). GR and K values are considered a reliable proxy to depict glacial–interglacial cycles, with high clastic input during cold and/or drier periods and high carbonate precipitation during warm and/or humid periods at Lake Ohrid. Spectral analysis was applied to investigate the climate signal and evolution over the length of the borehole. Linking downhole logging data with orbital cycles was used to estimate sedimentation rates and the effect of compaction was compensated for. Sedimentation rates increase on average by 14 % after decompaction of the sediment layers and the mean sedimentation rates shift from 45 cm kyr−1 between 0 and 110 m to 30 cm kyr−1 from 110 to 240 m b.l.f. Tuning of minima and maxima of gamma ray and potassium values versus LR04 extrema, in combination with eight independent tephrostratigraphical tie points, allows establishing of a robust age model for the downhole logging data over the past 630 kyr.

International audience; Volcanic ash produced during explosive eruptions can have very severe impacts on modern technological societies. Here, we use reconstructed patterns of fine ash dispersal recorded in terrestrial and marine geological archives to assess volcanic ash hazards. The ash-dispersal maps from nine Holocene explosive eruptions of Italian volcanoes have been used to construct frequency maps of distal ash deposition over a wide area, which encompasses central and southern Italy, the Adriatic and Tyrrhenian seas and the Balkans. The maps are presented as two cumulative-thickness isopach maps, one for nine eruptions from different volcanoes and one for six eruptions from Somma-Vesuvius. These maps represent the first use of distal ash layers to construct volcanic hazard maps, and the proposed methodology is easily applicable to other volcanic areas worldwide.

Active faulting is one of the main factors that induce deep-seated gravitational slope deformations (DGSDs). In this study, we investigate the relationships between the tectonic activity of the NW-SE normal fault system along Mt. Morrone, central Apennines, Italy, and the evolution of the associated sackung-type DGSD. The fault system is considered to be the source of M 6.5-7 earthquakes. Our investigations have revealed that the DGSD began to affect the Mt. Morrone SW slope after the Early Pleistocene. This was due to the progressive slope instability arising from the onset of the younger western fault, with the older eastern fault acting as the preferred sliding zone. Paleoseismological investigations based on the excavation of slope deposits across gravitational troughs revealed that the DGSD was also responsible for the displacement of Late Pleistocene-Holocene sediments accumulated in the sackung troughs. Moreover, we observed that the investigated DGSD can evolve into large-scale rock slides. Therefore, as well as active normal faulting, the DGSD should be considered as the source of a further geological hazard. Overall, our approach can be successfully applied to other contexts where active normal faults control the inception and evolution of a DGSD. © 2013 Elsevier B.V.

Textural and compositional features of pyroclastic products erupted during caldera-forming events often reveal the tapping of different portions of variably zoned magma chambers due to changing geometries of the conduit/vent systems. Here we report on ultrapotassic trachytic–phonolitic explosive eruptions of the Roman Province (central Italy), which show remarkable changes of textural features and glass compositions in the juvenile material, even if the bulk chemical composition is essentially constant. In each example, the lower eruption sequence contains whitish, crystal-poor (leucite-free), highly vesicular pumice, emplaced by early Plinian fallout and/or pyroclastic currents; upsection, the eruption sequence contains black, low porphyritic (sanidine + leucite-bearing), moderately vesicular, scoria or spatter, emplaced by major pyroclastic flows (red tuff with black scoria) and associated co-ignimbrite, coarse lithic-rich breccias. This suggests a shift from a central feeder conduit, tapping the central part of the magma chamber, to a ring fracture vent system, tapping the peripheral portions of the magma chamber, during caldera collapse. Key features of these evacuating magma chambers are the thermal and volatile concentration (Xvol) gradients that produce the observed textural and compositional spectrum of trachy-phonolitic rock types. In particular, the degrees of freedom during the crystallization of these ultrapotassic magmas are increased by the variation of the leucite stability field at different PH2O conditions. Both leucite-free and leucite-bearing differentiated ultrapotassic rock types can be produced in the course of individual eruptions, as a result of pre-eruptive conditions in the feeder magma, with no need to invoke different differentiation suites related to mantle source heterogeneities of parental magmas.

We describe the diagnostic lithological and chemical features of distal tephras from major Middle-Late Pleistocene (560-36 ka) explosive eruptions of the Colli Albani volcanic district, central Italy. In particular, we explore the time-dependent variability of the Sr and Nd isotope compositions as a tool for recognising and pinpointing individual Colli Albani tephra in distal settings. The distal tephras investigated are in lacustrine and fluvial sediments of central Apennine intermountain basins located 70 km-100 km east of Colli Albani. The recognition of the Colli Albani tephras is essentially based on the K-foiditic composition of their glass, which, within the Italian volcanological framework, is a distinctive character of the Colli Albani pyroclasts. In detail, these tephras are attributed to the following eruptive units: Tufo Pisolitico di Trigoria (561 +/- 2 ka); Tufo del Palatino-Tufo di Bagni Albule (530 +/- 2/527 +/- 2 ka), Tufo di Bagni Albule-Pozzolane Rosse air-fall sequence (517 +/- 1 to 500 +/- 3 ka), Pozzolane Rosse (457 +/- 4 ka), Villa Senni (365 +/- 4 ka), and Albano 5-7 (41 +/- 7 to 36 +/- 1 ka). These correlations are supported by Ar-40/Ar-39 dating of the distal tephras correlated to the Pozzolane Rosse (457.4 +/- 1.7 ka), Villa Senni (365 +/- 2 ka) and Albano 5-7 (41 +/- 9 ka) and by Sr-87/Sr-86 measured on clinopyroxene crystals and fresh glassy scoria from distal Colli Albani tephras that range from similar to 0.711 to similar to 0.709. These ratios are similar to those that characterise the individual proximal correlative units, and show the same decreasing trend over time. In contrast, the N-143/Nd-144 ratios for proximal and distal bulk samples and clinopyroxene increase from similar to 0.51212 to similar to 0.51215 from the oldest to the youngest tephra deposit. In summary, the study of Sr and Nd isotope compositions that is here applied on products from the Colli Albani volcanic district is a powerful, complementary tool to the more traditional tephrostratigraphic methods (e.g., componentry and electron microprobe analysis) for fingerprinting of distal tephras over a large region of the central Mediterranean, and over a large time interval, such as from 560 ka to 36 ka. (c) 2013 Elsevier Ltd. All rights reserved.

Laminated sediments of the maar lake Lago Grande di Monticchio in southern Italy exhibit a unique sequence of numerous primary tephra events that provide both insights into the Late Quaternary eruptive history of Italian volcanoes and an archive of essential marker horizons for dating and linking palaeoclimate records throughout the Central and Eastern Mediterranean. The acquisition of new sediment cores from this lake now extends the existing 100 ka-tephra record back to 133 ka BP, the end of the penultimate Glacial. The additional ca 30 m of sediments host a total number of 52 single tephra layers forming 21 tephra clusters that have been characterised on the basis of detailed geochemical and petrographical examinations. Tephras can be assigned to hitherto poorly known Plinian to sub-Plinian eruptive events of the nearby Campanian (Ischia Island, Phlegrean Fields), Roman (Sabatini volcanic district) and Aeolian-Sicilian volcanoes (Etna, Stromboli, Salina) and are dated according to the varve and sedimentation rate chronology of Monticchio sediments. The most prominent tephra layers within the interval of investigation - TM-25 and TM-27 - can be firmly correlated with Ionian Sea tephras X-5 (ca 105 ka BP) and X-6 (ca 108-110 ka BP). In addition, a further 26 tephra layers are correlated with radiometrically and radioisotopically dated volcanic events providing the basis for a robust revised tephrochronology of the entire Monticchio sediment sequence for the last 133 ka. © 2012 Elsevier Ltd.

The time span necessary to define a fault as 'active and capable' can mainly be derived from the framework of the regulations and the literature produced since the 1970s on risk estimation in engineering planning of strategic buildings. Within this framework, two different lines of thought can be determined, which have mainly developed in the USA. On the one side, there is a tendency to produce 'narrow' chronological definitions. This is particularly evident in the regulatory acts for the planning of nuclear reactors. The much more effective second line of thought anchors the chronological definitions of the terms 'active' and, therefore 'capable', to the concept of 'seismotectonic domain'. As the domains are different in different regions of the World, the chronological definition cannot be univocal; i.e., different criteria are needed to define fault activity, which will depend on the characteristics of the local tectonic domain and of the related recurrence times of fault activation. Current research on active tectonics indicates that methodological aspects can also condition the chronological choice to define fault activity. Indeed, this practice implies the use of earth science methods, the applications of which can be inherently limited. For example, limits and constraints might be related to the availability of datable sediments and landforms that can be used to define the recent fault kinematic history. For the Italian territory, we consider two main tectonic domains: (. a) the compressive domain along the southern margin of the Alpine chain and the northern and northeastern margins of the Apennines, which is characterised by the activity of blind thrusts and reverse faults; and (. b) the extensional domain of the Apennines and the Calabria region, which is often manifest through the activity of seismogenic normal and normal-oblique faults. In case (. a), the general geomorphic and subsurficial evidence of recent activity suggests that . a reverse blind fault or a blind thrust should be considered active and potentially capable if showing evidence of activity during the Quaternary (i.e., over the last 2.6Myr), unless information is available that documents its inactivity since at least the Last Glacial Maximum (LGM) (ca. 20ka). The choice of the LGM period as the minimum age necessary to define fault inactivity is related to practical aspects (the diffusion of the LGM deposits and landforms) and to the evidence that ca. 20. kyr to assess fault inactivity precautionarily includes a number of seismic cycles. In the extensional domains of the Apennines and Calabria region, the general geological setting suggests that the present tectonic regime has been active since the beginning of the Middle Pleistocene. Therefore, we propose that . a normal fault in the Italian extensional domain should be considered active and capable if it displays evidence of activation in the last 0.8 Myr, unless it is sealed by deposits or landforms not younger than the LGM. The choice of the LGM as the minimum age to ascertain fault inactivity follows the same criteria described for the compressive tectonic domain. © 2012 Elsevier B.V.

Benford's analysis is applied to the recurrence times of approximately 17,000 seismic events in different geological contexts of Italy over the last 6 years, including the Mt. Etna volcanic area and the seismic series associated with the destructive M (w) 6.3, 2009 L'Aquila earthquake. A close conformity to Benford's law and a power-law probability distribution for the recurrence times of consecutive events is found, as typical of random multiplicative processes. The application of Benford's law to the recurrence event times in seismic series of specific seismogenic regions represents a novel approach, which enlarges the occurrence and relevance of Benford-like asymmetries, with implications on the physics of natural systems approaching a power law behaviour. Moreover, we propose that the shift from a close conformity of Benford's law to Brownian dynamics, observed for time separations among non-consecutive events in the study seismic series, may be ruled by a periodical noise factor, such as the effects of Earth tides on seismicity tuning.

This article presents the preliminary results of research recently performed at La Ficoncella (Northern Latium) site. Discovered during the 1990s, the site of La Ficoncella has been inserted in recent years into a research program promoted by the fruitful collaboration between the Museum of Allumiere, Soprintendenza, the University of Rome " La Sapienza" , and CNR. The La Ficoncella site, still only at the beginning of excavation activities, has yielded various skeletal remains of Palaeoloxodon and a few other anatomical elements of other species, such as Bos primigenius and Equus sp., in association with four stone artefacts.The stratigraphic unit, still under study, contains fauna and lithic remains which could be dated to MIS 13, thanks to the presence of an ignimbritic layer at the top of the sequence, dating to MIS 12 (terminus ante quem). According to this data, the La Ficoncella site can be considered as an important source of information about the dynamics of human population and the techno-economic relationship between humans and elephants during the early Middle Pleistocene in central Italy. © 2011 Elsevier Ltd and INQUA.

Terra Nova, 23, 280–282, 2011 Abstract We question the approach followed by the Authors in identifying a presumed ‘new’ fault, and particularly the uncritical use made of topographic profiles, in which morphological features of different ages and origins are crudely correlated, creating the fake image of fault-tilting. We also point out the incorrect age attribution of faulted deposits – assumed without any analytical determination and/or stratigraphical framework – which has yielded serious errors as far as the timing of fault activity is concerned. These mistakes have led to incorrect conclusions and unavoidable repercussions for seismic hazard assessment of a region which has been just tragically struck by a disruptive earthquake.

The present paper refers to research conducted in the tectonic-karst depression of Campo Felice in the central Apennines (Italy), in which glacial, alluvial and lacustrine sediments have been preserved. Stratigraphic interpretations of sediments underlying the Campo Felice Plain are based on evidence obtained from nine continuous-core boreholes. The boreholes reach a depth of 120 m and provide evidence of five sedimentation cycles separated by erosion surfaces. Each cycle is interpreted as an initial response to a mainly warm stage, characterized by low-energy alluvial and colluvial deposition, pedogenesis, and limited episodes of marsh formation. In turn, a mainly cold stage follows during which a lake formed, and glaciers developed and expanded, leading to deposition of glacial and fluvioglacial deposits. The chronological framework is established by eleven accelerator mass spectrometer 14C ages and three 39Ar–40Ar ages on leucites from interbedded tephra layers. These age determinations indicate five glacial advances that respectively occurred during marine oxygen isotope stages 2, 3–4, 6, 10 and 14.

International audience

On 6 April 2009, at 01:32 GMT, an Mw 6.3 seismic event hit the central Apennines, severely damaging the town of L'Aquila and dozens of neighboring villages and resulting in approximately 300 casualties (Istituto Nazionale di Geofisica e Vulcanologia, http://www.ingv.it; MedNet, http://mednet.rm.ingv.it/procedure/events/QRCMT/090406_013322/qrcmt.html). This earthquake was the strongest in central Italy since the devastating 1915 Fucino event ( Mw 7.0). The INGV national seismic network located the hypocenter 5 km southwest of L'Aquila, 8–9 km deep. Based on this information and on the seismotectonic framework of the region, earthquake geologists traveled to the field to identify possible surface faulting (Emergeo Working Group 2009a, 2009b). The most convincing evidence of primary surface rupture is along the Paganica fault, the geometry of which is consistent with seismological, synthetic aperture radar (SAR) and GPS data. Investigation of other known normal faults of the area, i.e. , the Mt. Pettino, Mt. San Franco, and Mt. Stabiata normal faults suggested that these structures were not activated during the April 6 shock (Emergeo Working Group 2009a, 2009b). In this report, we first describe the seismotectonic framework of the area, and then we present the field information that supports the occurrence of surficial displacement on the Paganica fault. The shock of 6 April 2009 occurred in a region that has been struck by past earthquakes (CPTI Working Group 2004; Figure 1) and is in an Apennine sector that contains a complex array of active normal faults ( e.g. , Barchi et al. 2000; Galadini and Galli 2000; Boncio et al. 2004; Roberts and Michetti 2004). In the central Apennines, active faulting and earthquakes result from the ongoing extensional tectonics. The strongest earthquakes in the CPTI04 seismic catalog (CPTI Working Group 2004) occurred on 9 September 1349 ( Mw 6.5) and 2 February …

New 40 Ar/ 39 Ar and 14 C ages have been found for the Albano multiple maar pyroclastic units and underlying paleosols to document the most recent explosive activity in the Colli Albani Volcanic District (CAVD) near Rome, Italy, consisting of seven eruptions (Albano 1 = oldest). Both dating methodologies have been applied on several proximal units and on four mid-distal fall/surge deposits, the latter correlated, according to two current different views, to either the Albano or the Campi di Annibale hydromagmatic center. The 40 Ar/ 39 Ar ages on leucite phenocrysts from the mid-distal units yielded ages of ca. 72 ka, 73 ka, 41 ka and 36 ka BP, which are indistinguishable from the previously determined 40 Ar/ 39 Ar ages of the proximal Albano units 1, 2, 5 and 7, thus confirming their stratigraphic correspondence. Twenty-one 14 C ages of the paleosols beneath Albano units 3, 5, 6 and 7 were found for samples collected from 13 proximal and distal sections, some of which were the same sections sampled for 40 Ar/ 39 Ar measurements. The 14 C ages were found to be stratigraphically inconsistent and highly scattered, and were systematically younger than the 40 Ar/ 39 Ar ages, ranging from 35 ka to 3 ka. Considering the significant consistence of the 40 Ar/ 39 Ar chronological framework, we interpret the scattered and contradictory 14 C ages to be the result of a variable contamination of the paleosols by younger organic carbon deriving from the superficial soil horizons. These results suggest that multiple isotopic systems anchored to a robust stratigraphic framework may need to be employed to determine accurately the geochronology of the CAVD as well as other volcanic districts.