We apply a novel computational approach to assess, for the first time, volcanic ash dispersal during the Campanian Ignimbrite (Italy) super‐eruption providing insights into eruption dynamics and the ...impact of this gigantic event. The method uses a 3D time‐dependent computational ash dispersion model, a set of wind fields, and more than 100 thickness measurements of the CI tephra deposit. Results reveal that the CI eruption dispersed 250–300 km3 of ash over ∼3.7 million km2. The injection of such a large quantity of ash (and volatiles) into the atmosphere would have caused a volcanic winter during the Heinrich Event 4, the coldest and driest climatic episode of the Last Glacial period. Fluorine‐bearing leachate from the volcanic ash and acid rain would have further affected food sources and severely impacted Late Middle‐Early Upper Paleolithic groups in Southern and Eastern Europe.
Key Points
A new methodology to calculate ash dispersal of a super‐eruption was presented
Ash dispersal of the Campanian Ignimbrite super‐eruption was fully reconstructed
The impact of the Campanian Ignimbrite ash fallout was quantified and discussed
A review of the existing chronological, stratigraphic and chemo-petrologic data of the major eruptive units from the early phase of activity (800–390 ka) in the Monti Sabatini Volcanic District ...(MSVD), belonging to the ultra-potassic magmatic region of central Italy, is presented along with new radioisotopic age determinations and geochemical analyses. Through the combined use of electron microprobe glass compositions, selected trace-element compositions, and single-crystal 40Ar/39Ar age determinations, we provide a new chrono- and chemo-stratigraphic classification of the products emplaced in the 800–390 ka time interval. Besides giving insights on the petrologic evolution of the Roman Comagmatic Region, the large dataset provides fundamental information that is applicable to tephrostratigraphic studies in the wide region encompassing the Tyrrhenian Sea margin to the Adriatic Sea basin. Distal tephras from this volcanic activity also act as important geochronologic markers for the coastal sedimentary successions deposited in response to glacio-eustatic fluctuations, as well as for successions in the Quaternary tectonic basins of the Central and Southern Apennines. An innovative approach based on the use of discrimination diagrams of Zr/Y vs Nb/Y ratios for fingerprinting altered volcanic rocks – recently developed and successfully employed in archaeometric studies – is here combined to the glass compositions for classifying the MSVD deposits and tested on two distal tephra layers, showing its potentiality for tephrostratigraphic correlation.
•We review the literature on the chronostratigraphy of Monti Sabatini Volcanic District.•We integrate a large set of new geochemical and geochronological analyses.•We provide the chrono- and chemo-stratigraphic framework of the early explosive phase.•We apply a new trace-element based criterion for identification of the distal tephra.•We provide two case-histories demonstrating applicability of the proposed correlation method.
The Mount Vettore normal fault ruptured between August and October 2016, sourcing three earthquakes of Mw 6.2, 6.1, and 6.6. The first one caused the death of 299 people, while the entire sequence ...reached the highest macroseismic intensity levels in Italy since the catastrophic 1915 Fucino event (Mw 7.1). This fault was known to be one of the historically dormant faults of the Italian Apennines, and its sudden activation, not preceded by any foreshocks, has caught people and scientists off guards. We describe here the results from three new paleoseismic trenches opened across splays of the main antithetic fault that ruptured at surface on 30 October together with the 30‐km‐long Mount Vettore master fault. Data account for six surface faulting events since 9 ka, with a return time of 1.8 ± 0.3 kyr. The penultimate, probably stronger earthquake occurred in Late Roman times, perhaps in 443 AD, when also Rome suffered damage to its monumental buildings. Once again, paleoseismology turns out to be a powerful tool in seismic hazard assessment, especially for earthquakes that recur hundreds or thousands of years apart.
Plain Language Summary
Twenty years before the frightful central Italy earthquake of 2016 (Mw 6.6), early paleoseismic trenches revealed the existence and Holocene activity of the Mount Vettore fault system, in the Italian Apennines. New trenches excavated across the 2016 surface ruptures have allowed to define five paleoearthquakes of similar magnitude, the last one occurred in Late Roman period, when also the far monumental building of Rome were damaged. By joining the results of the new paleoseismic analyses with those published 20 years ago, the authors have found that the return time for such a class of magnitude earthquakes is about 1,800 years.
Key Points
Three new paleoseismic trenches have been excavated across the Mount Vettore fault system
Recurrence time for the past five, 2016‐like earthquakes (Mw 6.6) is about 1,800 years
The largest earthquakes sourced by the Mount Vettore fault damaged the most famous monuments in Rome
The Aurelian Mammal Age for peninsular Italy was introduced on the basis of faunal assemblages mainly recovered at sites along the Via Aurelia west of Rome. These sites exposed a set of sedimentary ...deposits currently attributed to the Aurelia and to the Vitinia Formations correlated with MIS 9 and MIS 7, respectively. In the present paper we reconstruct the geologic-stratigraphic setting in the western sector of Rome within the wider context of glacio-eustatically controlled, geochronologically constrained aggradational successions defined for this region. We present a chronostratigraphic study based on dedicated field surveys, that, combined with five new 40Ar/39Ar ages and eighteen trace-element and EMP glass analyses of volcanic products, allow us to revise age and correlation with the Marine Isotopic Stages for 10 sites out of 12 previously attributed to the Aurelia Formation and the Torre in Pietra Faunal Unit. In particular, we demonstrate a MIS 13/MIS 11 age for several sections along the Via Aurelia between Malagrotta and Castel di Guido. Based on this new geochronological framework, the first occurrences of Canis lupus and Vulpes vulpes in Italy are antedated to MIS 11, within the Fontana Ranuccio Faunal Unit of the Galerian Mammal Age, consistent with the wider European context. This contribution is intended as the groundwork for a revision of the Middle Pleistocene Mammal Ages of the Italian peninsula, according to the improved chronostratigraphy of the geologic sections hosting the faunal assemblages.
•We provide precise chronostratigraphic framing to several archaeologic sites in the area of Rome.•We provide new geochronologic constraints to the faunal assemblages of the Aurelian Mammal Age.•We revise the chronology of Castel di Guido, Malagrotta and Riano archaeological sites.•We revise the depositional context of La Polledrara di Cecanibbio archaeological site.•We revise the first occurrences of Canis lupus and Vulpes vulpes in Italy.
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.
We present new 40Ar/39Ar data which allow us to refine the recurrence time for the most recent eruptive activity occurred at Colli Albani Volcanic District (CAVD) and constrain its geographic area. ...Time elapsed since the last eruption (36 kyr) overruns the recurrence time (31 kyr) in the last 100 kyr. New interferometric synthetic aperture radar data, covering the years 1993–2010, reveal ongoing inflation with maximum uplift rates (>2 mm/yr) in the area hosting the most recent (<200 ka) vents, suggesting that the observed uplift might be caused by magma injection within the youngest plumbing system. Finally, we frame the present deformation within the structural pattern of the area of Rome, characterized by 50 m of regional uplift since 200 ka and by geologic evidence for a recent (<2000 years) switch of the local stress‐field, highlighting that the precursors of a new phase of volcanic activity are likely occurring at the CAVD.
Key Points
The time elapsed since the last eruption overruns the recurrence time in the last 100 kyr
Maximum uplift rates (>2 mm/yr) are concetrated in the area hosting the most recent (<200 ka) vents
We suggest that the observed uplift might be the result of magma injection within the youngest plumbing system of the volcano
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.
The cored succession of the Acerno basin, a tectonic palaeolake located in the southern Apennines (Italy), represents a key point of the Italian tephrostratigraphic network for the Quaternary. Trace ...element and isotope (87Sr/86Sr and 143Nd/144Nd) data have been acquired on bulk rock, glassy groundmass and separated minerals (feldspar and pyroxene phenocrysts) from twenty-one tephra layers, dated between ∼570 and 470 ka, embedded in the lacustrine sediments of the basin. The already available major element compositions have been here combined with the newly acquired data. The whole dataset provides a full geochemical characterization of the tephra that strengthens and improves previous attempts to identify their volcanic sources and potential correlatives. In this context, several previously proposed correlations among distal archives have been here confuted. The geochemical fingerprints highlight that the volcanic record preserved in the Acerno lacustrine succession can be attributed to the explosive activity of the Roccamonfina, Colli Albani, Sabatini, Pontian islands (Latium region, Central Italy) and the Neapolitan Volcanic Area (Campania region, South Italy), providing new insights to enhance the current knowledge on the Middle Pleistocene volcanic record in Italy. Moreover, tephra attributions suggest still unknown eruptive activity of such volcanoes during the Quaternary. From this perspective, our study testifies how difficult it is to precisely correlate different geological archives even in a very short time interval. Such a difficulty arises from a large number of volcanic events concentrated in a relatively short time span, with products of similar chemical composition, and from the incomplete characterization of the successions in proximal outcrops. A thorough reconstruction of the eruptive history of these volcanic complexes requires a wider and denser study of distal archives, alongside further investigations in proximal areas.
•Acerno tephra layers record Middle Pleistocene activity of the Italian volcanoes.•Tephra attributions suggest still unknown explosive activity between ∼570 and 470 ka.•Trace elements and radiogenic isotopes allow to unambiguously identify sources.•The geochemical signature allows reliable inter-archive correlations.
We report on the newly discovered lava flow that erupted in the Colli Albani Volcanic District, which is the most recent and, geochemically the most peculiar effusive event recognised in the entire ...ultrapotassic Roman Province (Central Italy).
This lava flow is associated with the Monte Due Torri scoria cone, located approximately 5km south of the Albano hydromagmatic centre (69–36ka). The Monte Due Torri scoria cone displays well-preserved morphological characteristics and the 40±7ka age determined for the associated lava flow indicates that its activity was nearly contemporaneous to the most recent, explosive activity that occurred at the Albano centre from 41 to 36ka.
By comparing chemical and petrological features of the Monte Due Torri lava flow, Albano products, and older products (>69ka), we show that the youngest Colli Albani eruptions were fed by two new batches of parental magmas that originated in a phlogopite-bearing metasomatised mantle, each one feeding one of the two youngest eruptive cycles (at 69ka and 41–36ka). The trace element signature, e.g., very low Pb content, of primitive (MgO>3wt.%) magmas feeding the initiation of the hydromagmatic activity at Albano (69ka) and the subsequent effusive activity at Monte Due Torri (40ka) indicates that a magma chamber located in the deep anhydrite-bearing dolomite formation was tapped. However, the polygenic activity, the changes in magma composition, and the variable thermometamorphic clasts occurring in the hydromagmatic deposits (recording variable substrata) suggest, particularly for the Albano eruptive centre, a more complex plumbing system consisting of at least two more magma chambers at a shallower depth, i.e., in the Mesozoic limestone and Pliocene pelite formations.
The large amount of stratigraphic, volcanological, and geochemical data collected for the Colli Albani Volcanic District, one of the main districts in the ultrapotassic Roman Province, enable us to contribute insights into the still open debate regarding the temporal variation of the metasomatised mantle source of the Italian potassic magmas. Based on our data, i.e., variation of radiogenic and trace elements over time, we suggest that the observed variation in the mantle source of the ultrapotassic magmas can be related to progressive consumption of the phlogopite component in the metasomatised source rather than the transition from lithosphere- to asthenosphere-derived magmatism and/or the transition from orogenic to anorogenic magmatism.
► Time-dependent geochemical variations in ultrapotassic magmas. ► Phlogopite exhaustion in the metasomatised mantle. ► Dolomite assimilation increasing sulphur activity. ► Pb trough in the spider diagram.
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