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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.

We report a palaeomagnetic investigation of the last full geomagnetic field reversal, the Matuyama-Brunhes (M-B) transition, as preserved in a continuous sequence of exposed lacustrine sediments in the Apennines of Central Italy. The palaeomagnetic record provides the most direct evidence for the tempo of transitional field behaviour yet obtained for the M-B transition. 40Ar/39Ar dating of tephra layers bracketing the M-B transition provides high-accuracy age constraints and indicates a mean sediment accumulation rate of about 0.2 mm yr-1 during the transition. Two relative palaeointensity (RPI) minima are present in the M-B transition. During the terminus of the upper RPI minimum, a directional change of about 180 o occurred at an extremely fast rate, estimated to be less than 2 o per year, with no intermediate virtual geomagnetic poles (VGPs) documented during the transit from the southern to northern hemisphere. Thus, the entry into the Brunhes Normal Chron as represented by the palaeomagnetic directions and VGPs developed in a time interval comparable to the duration of an average human life, which is an order of magnitude more rapid than suggested by current models. The reported investigation therefore provides high-resolution integrated palaeomagnetic and radioisotopic data that document the fine details of the anatomy and tempo of the M-B transition in Central Italy that in turn are crucial for a better understanding of Earth's magnetic field, and for the development of more sophisticated models that are able to describe its global structure and behaviour.

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.

Integrated electron microprobe analyses (EMPAs) on glass and Sr–Nd isotope analyses have been performed on 17 tephras from the Middle Pleistocene Mercure lacustrine succession, southern Apennines. Two 40Ar/39Ar ages and the recognition of four relevant tephras from Colli Albani, Sabatini and possibly Roccamonfina volcanoes allowed us to ascribe the investigated succession to the late Marine Isotope Stage (MIS) 15–12 interval (560–440 ka). The Sr–Nd isotopes and major element glass compositions allowed us to attribute 10 out of the other 13 tephras to a poorly known activity of the Roccamofina volcano, whereas two layers were tentatively attributed to previously unknown Middle Pleistocene activity of Ponza Island or Campanian volcanoes, and one to Salina Island. The tephrostratigraphic correlation of the Mercure tephras with the Acerno lacustrine pollen record (Campania) also allowed us to evaluate the climatostratigraphic position of the tephras within the framework of the MIS 15–12 climatic variability. These results were obtained by combining the Sr–Nd isotope ratio with EMPA and 40Ar/39Ar geochronological data. This confirms the notable consistency of this approach for studying the Mediterranean Middle Pleistocene tephrostratigraphy, which, despite its great potential for both volcanology and Quaternary studies, has been hitherto barely explored.

We present new stratigraphic, palaeomagnetic, 87Sr/86Sr and 40Ar/39Ar data from a lacustrine succession of the Sulmona basin, central Italy, which, according to an early study, included six unconformity-bounded lacustrine units (from SUL6, oldest, to SUL1, youngest) spanning the interval >600 to 2 ka. The results of the present study, on the one hand confirm some of the previous conclusions, but by contrast reveal that units SUL2 and SUL1, previously attributed to the Holocene, are actually equivalent to the older SUL6 and SUL5 units – here dated to ∼814–>530 ka and ∼530–

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.

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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

Morphological, stratigraphical and structural investigations integrated with palaeomagnetic and tephrostratigraphic studies and 40Ar/39Ar measurements allowed us to define the Quaternary tectonic–sedimentary evolution of the epicentral area of the L'Aquila 2009 earthquake (Mw 6.3). This area roughly matches the Paganica–San Demetrio–Castelnuovo (PSC) intermountain basin filled by a fluvio-lacustrine succession that is variously deformed by normal faults. At its early stage (Early Pleistocene; ca 2 Ma), the basin hosted a lake that was characterised by whitish carbonate silt and mud deposition. Towards the end of the Early Pleistocene, this was partly filled by a south-eastward prograding deltaic system. The south-easternmost portion of the deltaic system was successively abandoned and eroded, while sedimentation of a braided river system developed in a smaller area westwards. Before 780 ka, this fluvio-lacustrine system (the Lower PSC syntheme) ended, and the area underwent erosional and pedogenic processes. These processes continued up to >460 ka, with the onset of fluvial gravel and volcanic-rich silty sand deposition over a narrow area of the south-western PSC basin (an earlier unit of the Upper PSC syntheme, early Middle Pleistocene). Around 460 ka, when most of this area was again subjected to denudational processes, the sedimentation migrated into the previously exposed north-western area of the PSC basin, where fluvial/alluvial sediments were deposited, between ca 460 ka and ca 350 ka (a later unit of the Upper PSC syntheme). Between ca 350 ka and the present, the sedimentation continued uninterrupted in a slight westwards restricted area of the PSC basin (Upper–Late PSC syntheme). The significant contraction of the basin, the shifting of its depocentre, the variation in its geometry and in the spatial distributions and thicknesses of the units constituting the Lower, Upper and Late PSC synthemes, provide evidence for strong tectonic control. This resulted in progressive reduction of the activity of the south-easternmost tectonic structures and parallel migration of the fault activity on the westernmost structures. In this perspective, the fault system responsible for the L'Aquila 2009 earthquake can be seen as the most recent expression of a long-lasting westwards polarised process of tectonic activity transfer.

SUMMARY Urgent urban-planning problems related to the 2009 April, Mw 6.3, L’Aquila earthquake prompted immediate excavation of palaeoseismological trenches across the active faults bordering the Aterno river valley; namely, the Mt. Marine, Mt. Pettino and Paganica faults. Cross-cutting correlations amongst existing and new trenches that were strengthened by radiocarbon ages and archaeological constraints show unambiguously that these three investigated structures have been active since the Last Glacial Maximum period, as seen by the metric offset that affected the whole slope/alluvial sedimentary succession up to the historical deposits. Moreover, in agreement with both 18th century accounts and previous palaeoseismological data, we can affirm now that these faults were responsible for the catastrophic 1703 February 2, earthquake (Mw 6.7). The data indicate that the Paganica–San Demetrio fault system has ruptured in the past both together with the conterminous Mt. Pettino–Mt. Marine fault system, along more than 30 km and causing an Mw 6.7 earthquake, and on its own, along ca. 19 km, as in the recent 2009 event and in the similar 1461 AD event. This behaviour of the L’Aquila faults has important implications in terms of seismic hazard assessment, while it also casts new light on the ongoing fault linkage processes amongst these L’Aquila faults.

On 6 April, 2009, a Mw 6.3 earthquake struck L’Aquila and dozens of neighbouring villages (Abruzzo, central Italy) causing 308 deaths and with thousands injured. Within Italian seismicity, this was the strongest event since 1980 (Irpinia; Mw 6.9), and the first located so close to a large city since 1908 (Messina; Mw 7.3). Consistent data from an integrated approach (including stratigraphy, geomorphology, tephrochronology and paleoseismology) have allowed us to identify a 19-km-long, hitherto poorly known structure as being responsible for this earthquake (Paganica–San Demetrio fault system, PSDFS). The fingerprinting of four well-dated tephra layers and a detailed outline of the geomorphological and stratigraphic setting have provided the basis for assessing the behaviour of the PSDFS since its early activity, here dated at least ca 500 ka, to the present. The slip rate of the structure, calculated over different time windows, has fluctuated slightly ca 0.5 mm/yr. Paleoseismological analyses revealed the traces of the last surface-faulting events; thus, we unambiguously recognise the offset associated with the Mw 6.7 earthquake of 1703, which was previously related to other conterminous structures, along with an older comparable strong event, speculatively ascribed to an event purely known as the AD 801 central Apennine earthquake. This study shows that a long-term to short-term integrated approach is crucial in seismic hazard evaluation, especially when dealing with fault systems that are difficult to trace geomorphically, despite being capable of generating 2009-like earthquakes or even stronger events when conterminous structures are also involved.

Generally, the intensity and magnitude of explo- sive volcanic activity increase in parallel with SiO2 content. Pyroclastic-flow-forming eruptions in the Colli Albani ultrapotassic volcanic district (Italy) represent the most striking exception on a global scale, with volumes on the order of tens of cubic kilometres and K-foiditic composi- tions (SiO2 even

In the present work we analyse one of the active normal faults affecting the central Apennines, i. e. the Mt. Morrone normal fault system. This tectonic structure, which comprises two parallel, NW-SE trending fault segments, is considered as potentially responsible for earthquakes of magnitude >= 6.5 and its last activation probably occurred during the second century AD. Structural observations performed along the fault planes have allowed to define the mainly normal kinematics of the tectonic structure, fitting an approximately N 20° trending extensional deformation. Geological and geomorphological investigations performed along the whole Mt. Morrone south-western slopes permitted us to identify the displacement of alluvial fans, attributed to Middle and Late Pleistocene by means of tephro-stratigraphic analyses and geomorphological correlations with dated lacustrine sequences, along the western fault branch. This allowed to evaluate in 0.4 ± 0.07 mm/year the slip rate of this segment. On the other hand, the lack of synchronous landforms and/or deposits that can be correlated across the eastern fault segment prevented the definition of the slip rate related to this fault branch. Nevertheless, basing on a critical review of the available literature dealing with normal fault systems evolution, we hypothesised a total slip rate of the fault system in the range of 0.4 ± 0.07 to 0.8 ± 0.09 mm/year. Moreover, basing on the length at surface of the Mt. Morrone fault system (i. e. 22-23 km) we estimated the maximum expected magnitude of an earthquake that might originate along this tectonic structure in the order of 6.6-6.7. © 2009 Springer-Verlag.

For the first time a stratigraphic framework has been provided for several Palaeolithic and possible Mesolithic occurrences of the Campanian Apennine, on the basis of the numerous manifestations recognized at Frigento (Avellino). Knowledge of the Palaeolithic peopling of the mountainous region of southern Italy was, until now, extremely poor. In 2006 a geoarchaeological project identified a stratified sequence comprising four main pedological units intercalated with no less than six Late Pleistocene and Holocene tephra layers. Five archaeological horizons indicating both Middle and late Palaeolithic (and/or Mesolithic) occupations were precisely located in the sequence. The latter suggest affinities to some advanced Epigravettian industries of central-southern Italy, previously unknown in the region. All Palaeolithic technologies show original adaptations to the silica-rich argillites of the area, or pietra di Frigento. Pour la première fois, nous avons établi à Frigento (Avellino) un cadre stratigraphique pour quelques sites paléolithiques et probablement mésolithiques de l’Apennin campanien. La connaissance du peuplement paléolithique des montagnes de l’Italie du Sud est demeurée jusqu’à présent très modeste. En 2006, un projet géoarchéologique a permis d’identifier une stratification dans laquelle quatre unités pédologiques principales étaient intercalées avec six couches de téphra du Pléistocène supérieur et de l’Holocène.La même stratigraphie comprenait cinq niveaux archéologiques caractérisés par des outillages du Paléolithique moyen et terminal et/ou mésolithiques.La composante paléolithique terminale/mésolithique révèle des affinités avec les phases récentes des industries de l’Epigravettien “italique” central et méridional. Ces éléments étaient inconnus en Campanie. La technologie lithique est liée à la proximité d’affleurements de schistes argileux pietra di Frigento. Per la prima volta si è potuta stabilire un’intelaiatura stratigrafica rigorosa per talune manifestazioni paleolitiche e probabilmente mesolitiche dell’Appennino campano, sulla base delle numerose testimonianze segnalate a Frigento (Avellino). Fino a oggi la conoscenza del popolamento umano nel territorio montuoso dell’Italia meridionale era rimasta estremamente povera. Nel 2006 uno specifico programma geoarcheologico ha condotto a individuare una successione stratificata comprendente quattro unità pedologiche principali intercalate a non meno di sei tefra del Pleistocene superiore e dell’Olocene. Nella sequenza sono stati riconosciuti e ubicati con precisione cinque orizzonti archeologici connessi a occupazioni del Paleolitico medio e del Paleolitico terminale e/o Mesolitico. Queste seconde rivelano affinità con industrie centro-meridionali dell’Epigravettiano recente-finale, finora ignote nella regione. Tutte le tecnologie paleolitico-mesolitiche mostrano adattamenti originali agli argilloscisti silicei del territorio pietra di Frigento.

Significant new information shows that the Campanian Ignimbrite (CI) eruption from the Phlegrean Fields, southern Italy, was much larger than hitherto supposed and in fact one of the largest late Quaternary explosive events. The eruption can be dated to 40,000 calendar years ago, within the interval of the so-called Middle to Upper Paleolithic 'transition'. Its position can be precisely correlated with a number of other environmental events, including Heinrich Event 4 (HE4), the Laschamp excursion, and a particular cosmogenic nuclide peak. In view of this unique combination of factors, we studied the CI volcanic catastrophe with particular attention to its impact on climate and human ecosystems, including potential interference with ongoing processes of cultural evolution (biological evolution is best left aside for the moment). The contribution of this research is chronological and ecological. The CI volcanic event provides an unequalled means of correlating stratigraphic sequences across Western Eurasia, either directly or indirectly, and affords a unique opportunity to establish the age and climatic context of important archaeological sequences. Ecologically, the CI eruption inevitably interacted with the beginning of HE4 in terms of atmospheric feedback systems. Their combined forcing produced a sudden and at least hemispheric climatic deterioration; a 'volcanic winter' scenario cannot be ruled out. Paleolithic occupation was severely altered throughout the direct-impact zone of the eruption and likely along fringe areas in southern and southeastern Europe. The above observations call for a reconsideration of the processes and rhythms involved in the Middle to Upper Paleolithic 'transition'. A tentative model is suggested that links the exceptional environmental stress at 40,000 BP with processes already active in Paleolithic societies, leading to a period of accelerated change in cultural configurations. These eventually evolved into an Upper Paleolithic proper at a later date. The evidence to invoke allochthonous cultural input or invasionist scenarios is not considered compelling.

The Campanian Ignimbrite (CI) eruption, dated by 40Ar/39Ar and various stratigraphic methods to ca. 39,000 cal BP, generated a massive ash plume from its source in southern Italy across Southeastern and Eastern Europe. At the Kostenki-Borshchevo open-air sites on the Middle Don River in Russia, Upper Paleolithic artifact assemblages are buried below, within, and above the CI tephra (which is redeposited by slope action at most sites) on the second terrace. Luminescence and radiocarbon dating, paleomagnetism, and soil and pollen stratigraphy provide further basis for correlation with the Greenland and North Atlantic climate stratigraphy. The oldest Upper Paleolithic occupation layers at Kostenki-Borshchevo may be broadly correlated with warm intervals that preceded the CI event and Heinrich Event 4 (HE4; Greenland Interstadial: GI 12-GI 9) dating to ca. 45,000-41,000 cal BP. These layers contain an industry not currently recognized in other parts of Europe. Early Upper Paleolithic layers above the CI tephra are correlated with HE4 and warm intervals that occurred during 38,000-30,000 cal BP (GI 8-GI 5), and include an assemblage that is assigned to the Aurigancian industry, associated with skeletal remains of modern humans.

A~tephrostratigraphic record covering the Marine Isotope Stages (MIS) 1–15 was established for the DEEP site record of Lake Ohrid (Macedonia/Albania). Major element analyses (SEM-EDS/WDS) were carried out on juvenile fragments extracted from 12 tephra layers (OH-DP-0115 to OH-DP-2060). The geochemical analyses of the glass shards of all of these layers suggest an origin from the Italian Volcanic Provinces. They include: the Y-3 (OH-DP-0115, 26.68–29.42 cal ka BP), the Campanian Ignimbrite/Y-5 (OH-DP-0169, 39.6 ± 0.1 ka), and the X-6 (OH-DP-0404, 109 ± 2 ka) from the Campanian volcanoes, the P-11 of the Pantelleria Island (OH-DP-0499, 129 ± 6 ka), the Vico B (OH-DP-0617, 162 ± 6 ka) from the Vico volcano, the Pozzolane Rosse (OH-DP-1817, 457 ± 2 ka) and the Tufo di Bagni Albule (OH-DP-2060, 527 ± 2 ka) from the Colli Albani volcanic district, and the Fall A (OH-DP-2010, 496 ± 3 ka) from the Sabatini volcanic field. Furthermore, a comparison of the Ohrid record with tephrostratigraphic records of mid-distal archives related to the Mediterranean area, allowed the recognition of the equivalents of other less known tephra layers, such as the TM24-a/POP2 (OH-DP-0404, 101.8 ka) from the Lago Grande di Monticchio and the Sulmona basin, the CF-V5/PRAD3225 (OH-DP-0624, ca. 162 ka) from the Campo Felice basin/Adriatic Sea, the SC5 (OH-DP-1955, 493.1 ± 10.9 ka) from the Mercure basin, and the A11/12 (OH-DP-2017, 511 ± 6 ka) from the Acerno basin, whose specific volcanic sources are still poorly constrained. Additionally, one cryptotephra (OH-DP-0027) was identified by correlation of the potassium XRF intensities from the DEEP site with those from short cores of previous studies from Lake Ohrid. In these cores, a maximum in potassium is caused by glass shards, which were correlated with the Mercato tephra (8.43–8.63 cal ka BP) from Somma-Vesuvius. With the tephrostratigraphic work, a consistent part of the Middle Pleistocene tephrostratigraphic framework of Italian volcanoes was for the first time extended as far as to the Balkans. The establishment of the tephrostratigraphic framework for the Lake Ohrid record provides important, independent tie-points for the age-depth model of the DEEP site sequence, which is a prerequisite for paleoclimatic and -environmental reconstructions. Furthermore, this age-depth model will help to improve and re-evaluate the chronology of other, both undated and dated tephra layers from other records. Thus, the Lake Ohrid record is candidate to become the Rosetta stone for the central Mediterranean tephrostratigraphy, especially for the hitherto poorly known and explored lower Middle Pleistocene period.

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.

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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.

Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been made in order to develop a procedure for the paleoseismological analysis of bedrock fault scarps. The CF fault has been responsible for the formation of an impressive limestone fault scarp. Geomorphologic work on the CF basin and related fault indicated that the scarp originated from tectonic fault displacements. Three morphologic units have been distinguished along the fault scarp and defined as morphosome M1 (lowest part of the scarp), M2 and M3 (the uppermost part). These units display different karstic features, which are the result of their different duration of exposure to weathering. Micromorphologic analyses focused on the morphosome M1, along which the CF fault plane is exposed for a height ranging between 4 and 7 m. These analyses were aimed at defining differently weathered bands located at various heights, and parallel to the fault scarp top and base. The presence of these bands suggests repeated fault movements. The exposed fault surface displays a low-grade biokarstic weathering due to the action of epilithic and endolithic organisms. The biokarst distribution is, however, inhomogeneous and conditioned by the presence of nourishing elements, moisture and by light intensity. An area preferentially affected by the biokarstic processes develops as a band at the bedrock–soil contact at the base of the scarp. Roughness and colour analyses were made to identify uplifted bands which previously formed at the bedrock–soil contact. The roughness analysis was made using a microroughness-meter along 20-cm long horizontal transects repeated each 20 cm of fault height for the entire morphosome M1, at various sites along the scarp. The roughness variance data, plotted vs. the fault height, failed to identify differently weathered bands of paleoseismological interest. This result is probably due to the complex distribution of biokarst along the investigated fault plane. More reliable results have been obtained by areal analysis of the variation of the colour rendering of the rocks exposed along the fault plane at different sites. Photographic images of large portions of fault surfaces have been processed with standard graphic computer programs. The variations of colour indicated the presence of bands at various heights along the fault plane. Two uplifted bands have been recognised at all the investigated sites suggesting two displacement events (E1 and E2). A preliminary chronological framework for these two events, the youngest of which affected the CF fault, can be derived from the paleoseismological data available for the southernmost branch of the regional fault system that includes the CF fault. According to these data, E1 may have occurred between 860 and 1300 AD, while E2 may have occurred at about 1900 BC. Work is in progress to define surface exposure ages of different parts of the fault plane by means of in situ produced cosmogenic 36 Cl. This procedure will give further chronological constraints for the age of E1 and E2 and will also permit to test the validity of the micromorphologic analysis of bedrock fault scarps for paleoseismological aims.

The dating of the Campanian Ignimbrite (CI) eruption to ∼37,000 cal yr B.P. draws attention to the coincidence of this volcanic catastrophe and the suite of coeval, Late Pleistocene biocultural changes that occurred within and outside the Mediterranean region. These included the Middle to Upper Paleolithic cultural transition and the supposed change from Neanderthal to “modern” Homo sapiens anatomy, a subject of sustained debate. No less than 150 km3 of magma were extruded in the CI eruption, the signal of which can be detected in Greenland ice cores. As widespread discontinuities in archaeological sequences are observed at or following the CI event, a significant interference with ongoing human processes in Mediterranean Europe is hypothesized.

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.

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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.

[1] 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 km 3 of ash over 3.7 million km 2 . 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. Citation: Costa, A., A. Folch, G. Macedonio, B. Giaccio, R. Isaia, and V. C. Smith (2012), Quantifying volcanic ash dispersal and impact of the Campanian Ignimbrite super-eruption, Geophys. Res. Lett., 39, L10310, doi:10.1029/2012GL051605.

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.

la relazione riporta le attività di acquisizione di indagini geofisiche effettuata (48 misure di rumore ambientale a stazione singole) e la successiva modellazione numerica della risposta sismica locale

rapporto tecnico-scientifico sulle raccomandazioni da usare negli interventi di progettazione e/o ristrutturazione derivate dai risultati delle indagini geofisiche e dalla modellazione numerica effettuata nonché gli interventi di stabilizzazione possibili da adottare per la riduzione del rischio associato a fenomeni di instabilità.

La presente relazione riporta le informazioni geologiche, geomorfologici dell'area di studio

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 Torn scoria cone, located approximately 5 km south of the Albano hydromagmatic centre (69-36 ka). The Monte Due Torn scoria cone displays well-preserved morphological characteristics and the 40 +/- 7 ka 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 36 ka. By comparing chemical and petrological features of the Monte Due Torn lava flow, Albano products, and older products (>69 ka), 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 69 ka and 41-36 ka). The trace element signature, e.g., very low Pb content, of primitive (MgO>3 wt.%) magmas feeding the initiation of the hydromagmatic activity at Albano (69 ka) and the subsequent effusive activity at Monte Due Torri (40 ka) 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. (C) 2011 Elsevier B.V. All rights reserved.

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.

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