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The connection between faults at surface, their subsurface geometry and earthquakes is a long-debated issue. The attempt of making such correlation is even more difficult when earthquakes are not strong enough to reach and break the topographic surface. Even in the latter case, the subsurface geometry of earthquake-causative-faults is not a trivial issue because of the difficulty of imaging the subsurface setting at seismogenic depths.We take as an example the area of southern Tuscany in Central Italy where several M≈4 strike-slip earthquakes were registered recently, the latest of which occurred in May 2022.The seismogenic role of transversal SW-NE striking faults in this area is debated as they do not show clear surface evidence even when releasing earthquakes and their recent and/or Quaternary evidence often a matter of discussion. For these reasons they can be extremely dangerous as they receive relatively little attention and are difficult to identify.We integrate seismic reflection profiles, surface kinematic data and the relocation of seismological data in order to identify and characterize strike-slip active faults geometry at depth in the Valdelsa basin of southern Tuscany. We show that the Montespertoli NE-trending fault, part of a wider (15–20 km) crustal-scale shear zone, is possibly responsible for the 2016 M=3.9 Castelfiorentino earthquake and discuss the role of transversal SW-NE striking faults in controlling the inner Northern Apennines seismicity.

Changes in groundwater flow in response to strong earthquakes are widely described in many tectonic environments. For example, a post-seismic discharge variation is often attributed to an increase of bulk permeability due to co-seismic fracturing and/or to a change in the role of faults in acting as conduits/barrier to groundwater flow.We take as an example the fractured aquifer of the Mts. Sibillini carbonate massif, in Central Italy, which were affected by a strong and prolonged extensional seismic sequence in 2016-17. The sequence was characterized by an M=6.5 event (mainshock), an M=6 event, an M=5.9 event, up to 60 M>4 events and several M>5 earthquakes. The strongest events caused rupturing of the topographic surface for a cumulative length in the order of 30 km and an important portion of aftershocks occurred at depths where groundwater is stored.As a response to the seismic sequence, the main NNW-directed groundwater flow was diverted to the west and a discharge deficit was observed at the foot-wall of the activated fault system with a relevant discharge increase, accompanied by geochemical variations, at the fault system hanging-wall.By integrating geo-structural reconstructions, seismological and ground deformation data, artificial tracer tests results and a 4-years discharge and geochemical monitoring campaign data, we show that the observed groundwater variations are due to a combination of permeability increase along the activated fault systems and hydraulic conductivity increase of the hanging-wall block due to fracturing, extension and subsidence, which determined a fast aquifers emptying. Seismicity temporarily triggered a change of the pre-existing predominant along-faults-strike NNW-SSE oriented regional flow to a west-directed flow, perpendicular to faults strike. We discuss the position of the aquifer with respect to the activated faults and how this affected the observed phenomena. REFERENCECambi, C., Mirabella, F., Petitta, M., Banzato, F., Beddini, G., Cardellini, C., ... & Valigi, D. (2022). Reaction of the carbonate Sibillini Mountains Basal aquifer (Central Italy) to the extensional 2016–2017 seismic sequence. Scientific Reports, 12(1), 1-13. DOI: 10.1038/s41598-022-26681-2

The ICDP STAR drilling project (Strain Meter Array) is a joint research project among different institutions that aims to study the fault slip behaviour of the low angle Alto Tiberina Fault (ATF) in the Northern Apennines, Italy. The ATF is an active low-angle normal fault (mean dip 20°) whose activity and mechanics is still debated. Therefore, STAR drilled and instrumented six shallow boreholes, providing an excellent opportunity to study creep at local scale and over periods of minutes to months, poorly constrained by other geophysical instruments.Two drilling campaigns were made in Fall 2021 and in Summer 2022, drilling a total of six 80-160 m deep vertical boreholes. Each borehole was instrumented with seismometers (three-component (3C) borehole geophones) and strainmeters (Gladwin Tensor Strainmeters, GTSM). Strainmeters are the only instruments capable of measuring small creep events, as has been demonstrated near other creeping faults, such as the creeping section of the strike-slip San Andreas fault near Parkfield. Two boreholes drilled the Mesozoic-Paleogene, Umbria-Marche carbonate succession (Maiolica, Marne a Fucoidi, Scaglia Bianca, Scaglia Rossa and Scaglia Variegata formations). The other four boreholes encountered the Neogene marls and turbidite sandstones (Schlier and Marnoso-Arenacea formations). Upon completion of the drilling operations, a suite of downhole logging measurements was performed in each borehole, comprising: total gamma ray, full wave sonic, electrical conductivity and temperature, caliper, resistivity, optical and acoustic borehole images. The sondes recorded data only in the deepest portion (open section) of the wellbore, except for the total gamma ray that run also in the cased section. The objective was to record the physical properties of the rocks in situ, and to reconstruct the spatial distribution and characteristics of the fractures (i.e. partially open, closed, thickness) and their connection with the geological structures mapped on the surface. Here we present a preliminary analysis of the logging data. In the carbonate units (i.e. Maiolica and Scaglia Rossa) the gamma ray shows low and flat curve (less than 30 cps) and P-wave velocity about 3 km/s. In the sandstone-marly units (Marnoso-Arenacea), encountered in three boreholes, the gamma ray records high values (about 80-100 cps) correlated mainly to marly intervals and P-wave velocity of 3-3.5 km/s. The hemipelagic marls of the Schlier Formation are characterized by high gamma ray (mean value of 80 cps) and by an average P-wave velocity of 3.5 km/s. These values will be compared with the results of laboratory analysis of samples, collected in similar lithologies, as well as with the results of logging performed in deeper wells drilled for commercial purposes. Through this comparison, we will evaluate the effect of depth (i.e. pressure) on the main physical properties of sedimentary rocks. The physical properties, in combination with the orientation and geometry of the discontinuities (fractures, veins, bedding), acquired by downhole logging, will contribute in building-up improved 3-D geological models of the ATF.

Fault displacement can be a source of hazard for critical infrastructures located in the nearby of a capable fault. This issue is usually addressed with zonation and avoidance strategies, but sometime the facilities have not this option. An alternative approach to assess likelihood of exceeding a certain level of displacement for pre-existing infrastructures is the Probabilistic Fault Displacement Hazard Analysis. Different empirical approaches have been proposed since the early 2000s to assess the probability of occurrence and the probability of exceedance of certain values of displacement, for both Primary and Distributed faulting, starting from the fault parameters. We propose the methodological approach used to gain the needed parameters and the results of the PFDHA applied to the Anghiari Fault, a poorly constrained NE-dipping segmented normal fault located in the Upper Tiber Valley (Italy) and belonging to the well-known Altotiberina low-angle normal fault system.In order to constrain the fault geometry and to select sites suitable for paleoseismologic trenching we performed geological survey, morphotectonic analysis and geophysical investigations. To assess the capability of the fault and its rate of activity we carried out a paleoseimic campaign, investigating several segments of the Anghiari fault. To obtain a multiscale evaluation of the fault slip rate, we collected samples to date paleosurfaces displaced by the fault with the cosmogenic nuclides methodology. At the end we performed the PFDHA obtaining curves and maps of hazard for both primary and distributed faulting, managing the uncertainties through various rupture scenario involving different fault segment.

The Italian Apennines is a slowly deforming area, despite not properly being an intraplate region. This is particularly true for the Northern Apennines, where~1ka) recurrence intervals. This makes earthquake geology a fundamental tool for characterizing the seismic hazard.The Anghiari fault is a 11 km-long segmented NE-dipping normal fault bounding the western side of the Upper Tiber Valley (Northern Apennines, Italy), and belonging to the well-known Altotiberina low-angle normal fault system. Here, we provide unprecedented evidence of the Holocene activity of the Anghiari fault through geological, geophysical and palaeoseismological investigations. The fault is composed of at least two nearly parallel splays. One splay runs at the base of the Pleistocene Anghiari ridge, downfaulting the late Quaternary alluvial deposits of the Tiber Valley against Middle Pleistocene continental deposits. The other splay is located within the Middle Pleistocene units of the Anghiari ridge. We focus on the latter. Detailed geomorphological analysis, geological mapping and near-surface geophysics, enabled us to select two sites for palaeoseismological trenching. Radiocarbon dating of faulted sediments provides constraints for late Holocene and historical surface faulting events significantly contributing to the estimation of the seismic hazard in the region.

Biodegradable and potentially biobased polyesteramide oligomers (PEA-Pro), obtained from melt condensation of sebacic acid and 3-amino-1-propanol, were characterized by nuclear magnetic resonance (NMR), matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrometry/mass spectrometry (MALDI-TOF/TOF-MS/MS), thermogravimetric analysis (TGA), and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). NMR analysis showed the presence of hydroxyl and amino terminal groups as well as carboxylic groups of the sebacate moiety. Hydroxyl and carboxyl termination had the same abundance, while the amine termination was 2.7-times less frequent. Information regarding the fragmentation pathways and ester/amide bond sequences was obtained by MALDI-TOF/TOF-MS/MS analysis performed on sodiated adducts of cyclic species and linear oligomers. Different end groups did not influence the observed fragmentation. Three fragmentation pathways were recognized. The β-hydrogen-transfer rearrangement, which leads to the selective scission of the –O–CH2– bonds, was the main mechanism. Abundant product ions originating from –CH2–CH2– (β–γ) bond cleavage in the sebacate moiety and less abundant ions formed by –O–CO– cleavages were also detected. TGA showed a major weight loss (74%) at 381 °C and a second degradation step (22% weight loss) at 447 °C. Py-GC/MS performed in the temperature range of 350–400 °C displayed partial similarity between the degradation products and the main fragments detected in the MALDI-TOF/TOF-MS/MS experiments. Degradation products derived from amide bonds were related to the formation of CN groups, in agreement with the literature.

The presence of a set of well-known turbidite successions, deposited in progressively E-migrating foredeep basins and subsequently piled up with east vergence, makes the Northern Apennines of Italy paradigmatic of the evolution of deepwater fold-and-thrust belts. This study focuses on the early Apenninic collisional stage, early Miocene in age, which led to the accretion of the turbidites of the Trasimeno Tectonic Wedge (TTW), in the central part of the Northern Apennines. Based on the interpretation of previously unpublished seismic reflection profiles with new surface geology data and tectonic balancing, we present a detailed tectonic reconstruction of the TTW. In the study area, the TTW is characterized by a W-dipping shaly basal décollement located at a depth of 1–5 km. The tectonic wedge isc. 5 km thick at its central-western part and tapers progressively eastwards toc. 1 km. The total shortening, balanced along a 33 km long cross-section, isc. 60 km, including 20 km (40%) of internal imbrication,c. 23 km of horizontal ENE-wards translation along the basal décollement andc. 17 km of passive translation caused by the later shortening of footwall units. Deformation balancing, constrained through upper Aquitanian – upper Burdigalian (c. 21–16 Ma) biostratigraphy, provides an average shortening rate ofc. 8.6 mm a–1. Internal shortening of the TTW shows an average shortening rate ofc. 4 mm a–1for this period.

The interaction between fluids and tectonic structures such as fault systems is a much-discussed issue. Many scientific works are aimed at understanding what the role of fault systems in the displacement of deep fluids is, by investigating the interaction between the upper mantle, the lower crustal portion and the upraising of gasses carried by liquids. Many other scientific works try to explore the interaction between the recharge processes, i.e., precipitation, and the fault zones, aiming to recognize the function of the abovementioned structures and their capability to direct groundwater flow towards preferential drainage areas. Understanding the role of faults in the recharge processes of punctual and linear springs, meant as gaining streams, is a key point in hydrogeology, as it is known that faults can act either as flow barriers or as preferential flow paths. In this work an investigation of a fault system located in the Nera River catchment (Italy), based on geo-structural investigations, tracer tests, geochemical and isotopic recharge modelling, allows to identify the role of the normal fault system before and after the 2016–2017 central Italy seismic sequence (Mmax = 6.5). The outcome was achieved by an integrated approach consisting of a structural geology field work, combined with GIS-based analysis, and of a hydrogeological investigation based on artificial tracer tests and geochemical and isotopic analyses.

Fault displacement is a localized source of hazard for infrastructure located near active and capable faults, such as critical buildings and distributed facilities. This issue can be overcome through zoning and avoidance strategies, but facilities may sometimes not benefit from this option. In the last 20 years, several authors have developed a probabilistic approach to analyse this hazard, known as probabilistic fault displacement hazard analysis (PFDHA), for both principal fault and distributed rupturing. In this work, we apply the approach proposed by YOUNGS et alii (2003) to the Anghiari-Citta di Castello fault, a NE-dipping normal fault located in the northern Apennines of Italy, which shows evidence of Quaternary activity. We explore two different rupturing scenarios to obtain displacement hazard curves and maps for different probabilities of exceedance in 200 years at different distances along and from the principal fault trace for both the principal and distributed rupturing. The expected displacement values for the principal fault rupturing are up to 130 cm for a return period of 10,000 years (2% in 200 years), and the distributed rupturing hazard is 3–4% of the principal fault rupturing hazard. It is null in the footwall of the fault and slightly variable in its hanging wall as a function of distance from the fault trace and fault tip. The variability of the distributed rupturing hazard within the first hundreds of metres from the principal fault can assist to define mitigation strategies for existing facilities located in proximity of the fault.

We have investigated the structural, thermal and morphological properties of lignin extracted from five distinct biomasses in order to establish the influence of the age of the source, environmental conditions during growth and quantity present. In fact, lignin is an integral part of cellulosic biomass and affects the structure, properties, processing and applications. Presence of lignin is critical for structural integrity but detrimental for converting biomass into new products. Aerial roots from banyan tree, sugarcane bagasse, bamboo, cornhusk and rice straw were selected to extract Klason lignin using the sulfuric acid approach. Extent of lignin in the samples varied from 9.14 to 23.77 %. Overall, compositional analysis showed that the lignin from the five sources had considerable variation, particularly in terms of the trace elements. Nevertheless, structure and properties of lignin extracted from five distinct biomasses was found to be independent of the age of the source, conditions during growth or quantity present in the biomass.

The dynamic of groundwater systems feeding several springs of the Sibillini Mountains was deeply affected by nine Mw 5.0÷6.5 seismic events occurred in central Italy starting from August 2016. The strongest shock occurred on October 30th 2016 about 5 km NNE of Norcia Town, 9 km below the surface, as a result of upper crust normal faulting on the nearly 30 km-long Mt Vettore - Mt Bove fault system, a NW-SE trending, SW-dipping fault system outcropping on the western slope of Mt Vettore, the highest peak of Sibillini Mountains. Soon after this event, a general increase of springs and rivers discharge and groundwater levels was observed both in the Visso and Norcia areas, west of the Sibillini Mountains. In the Visso area the hydrogeological changes due to the seismic sequence exhausted in the 2019, while nowadays both discharges and groundwater levels are still higher than before in the Norcia area. Discharge data of the main springs located east, south-east of the Sibillini Mountains were analysed to verify whether the general increase observed on the western side was associated to a decrease on the eastern and southern-east area. The results show that the springs located on the eastern side and southern-east side of Mt Vettore experienced a significant long-term discharge decrease. In this preliminary work, the analysis of the historical discharge series of the Pescara di Arquata spring (SE of Mt Vettore), and its relationship with the Standard Precipitation Index (SPI) shows that the very low discharge values recorded during the post-seismic period are not associated with SPI as low as documented in the past for similar discharges. Moreover, the stable isotopic composition of Pescara di Arquata water during the post-earthquake period is slightly different from that measured before the seismic events; this suggests that a lower amount of water having more enriched isotopic δ18O content reaches the spring after the seismic sequence. These aspects seem to indicate that groundwater circulation in the southern-east area of Sibillini Mountains has been affected by the 2016-2017 seismic sequence.

Starting from 24 August 2016, a long seismic sequence, including nine M-w > 5.0 earthquakes, struck a wide area of the Central Italy. A large amount of geological, geodetic, and seismological data envisages a complex system of NNW-SSE trending, seismogenic normal faults. These active tectonic structures are well known at the surface and consistent with previous seismotectonic studies. In order to improve the comprehension of the seismotectonic framework of this seismic sequence, we provide a novel reconstruction of the subsurface geology of the area close to the Norcia M-w 6.5 mainshock (30 October 2016), based on previously unpublished seismic reflection profiles and available geological data. All the data have been synthesized along a 47 km long, WSW-ENE trending geological cross section, interpreted down to a depth of 12 km. Comparing the subsurface geological model with the available seismological data, we find that the majority of seismicity is confined within the sedimentary sequence and does not penetrate the underlying basement. The basement has been constrained at depths of 8 to 11 km and coincides with the cutoff of the seismicity. We have also traced the trajectories of the seismogenic normal faults activated during this seismic sequence, reconciling the high-angle (dip>65 degrees) normal faults exposed at the surface, with their angle (dip < 50 degrees) at hypocentral depths. The results of this study may be useful for better understanding the rheological properties of the seismogenic rock volume, as well as the coseismic deformations of the topographic surface observed by geodetic techniques and field mapping.

During the last years, there has been an increasing interest in the valorization of the food-processing side streams due to their potentially valuable phytochemical content. Olive mill wastewater (OMWW), the main by-product of olive oil extraction process, are rich in polyphenolic compounds, widely known for their health-promoting benefits. However, different parameters--such as the distinct olive cultivar, ripeness of the fruit, processing techniques, climate, and storage conditions--play an important role in determining the specific quali-quantitative polyphenolic composition of OMWW. In this work, for the first time, we have characterized and compared the polyphenolic profile of different OMWW generated by centrifugal three-phase olive oil mills processing of two important Sicilian cultivars, Cerasuola and Nocellara etnea. Moreover, the correlated antioxidant activity and the stability of both OMWW samples stored at different conditions were evaluated. Our results show that even if OMWW are characterized by different and individual polyphenolic profile, both side streams have high levels of antioxidant activity. From a comparative point of view, we found that Cerasuola-OMWW showed higher values of total phenols (5.20 ± 0.21 g/l gallic acid), total flavonoids (2.28 ± 0.23 g/l catechin) and hydroxytyrosol content (821.86 ± 0.01 mg/l) respect to the analog parameters measured in Nocellara etnea-OMWW; these phytochemical values showed a significant stability in both OMWW samples stored at -20 °C for 6 months. Conversely, a decrease in the level of these compounds was observed in samples maintained at 4 or 25 °C for 45 days.

New functionalized Poly(ether sulfone)s having different molar ratio (10, 20, 30, 50, 70, 100 mol%) of 4,4-bis phenoxy pentanoic acid unit (diphenolic acid, DPA) units were synthesized and characterized by (1H and 13C)-NMR, MALDI-TOF MS, FT-IR, DSC and DMA analyses. The microstructural analysis of the copolymers, obtained by 13C-NMR using an appropriate statistical model, shows a random distribution of copolymer sequences, as expected. The presence of different amount of DPA units along the polymer chains affects the chemical and physical properties of the copolymers. The Tg and the contact angle values decrease as the molar fraction of DPA units increases, whereas the hydrophilicity increases. NMR and MALDI-TOF MS analyses show that all polymer chains are almost terminated with hydroxyl and chlorine as end groups. The presence of cyclic oligomers was also observed by MALDI-TOF MS analysis.

Report sui risultati delle analisi effettuate per la trasmissione «Petrolio» - RAI 2 su posate e piatti dichiarati biodegradabili e compostabili e residui di film plastici da impianti di compostaggio. (Prot CNR-IPCB n° 0000483 del 27/02/2020)

The accuracy of earthquake locations and their correspondence with subsurface geology depends strongly on the accuracy of the available seismic velocity model. Most modern methods to construct a velocity model for earthquake location are based on the inversion of passive source seismological data. Another approach is the integration of high-resolution geological and geophysical data to construct deterministic velocity models in which earthquake locations can be directly correlated to the geological structures. Such models have to be kinematically consistent with independent seismological data in order to provide precise hypocenter solutions. We present the Altotiberina (AT) seismic model, a three-dimensional velocity model for the Upper Tiber Valley region (Northern Apennines, Italy), constructed by combining 300 km of seismic reflection profiles, 6 deep boreholes (down to 5 km depth), detailed data from geological surveys and direct measurements of P- and S-wave velocities performed in situ and in laboratory. We assess the robustness of the AT seismic model by locating 11,713 earthquakes with a non-linear, global-search inversion method and comparing the probabilistic hypocenter solutions to those calculated in three previously published velocity models, constructed by inverting passive seismological data only. Our results demonstrate that the AT seismic model is able to provide higher-quality hypocenter locations than the previous velocity models. Earthquake locations are consistent with the subsurface geological structures and show a high degree of spatial correlation with specific lithostratigraphic units, suggesting a lithological control on the seismic activity evolution.

The Middle Valle Umbra (central Italy) is a NW-SE 20 km long and 10 km wide Quaternary extensional basin located in the internal sector of the Apennine chain. This area historically experienced strong earthquakes that caused significant damages to the outstanding historical heritage. The same area has been recently hit by the 2016 seismic sequence of Amatrice-Visso-Norcia. With the aim to reconstruct the buried geological structures of the basin, a multi-technique geophysical approach was performed. An extended campaign of ambient noise measurements was carried out to investigate the subsurface setting, and to identify the main geological units. We performed three 2D passive arrays to analyze two different sites within the basin; their aperture was between 150 and 752 m for one site and of 48 m for the other site, to characterize the geological units in terms of sediment thickness and shear-wave velocity profile. Data collected were processed with f-k and MSPAC analysis to extract dispersion curves with good resolution in a frequency range of 0.5–10 Hz and 4.5–18 Hz for the two sites respectively. Spectral ratios were computed for every single station ambient noise measurement performed and for all the stations of the bigger array. Our final target is to extend these results to the whole valley, in order to retrieve the attitude of the main geological units and propose a reliable reconstruction of the subsurface geometry of the basin. Another point of this work is to evaluate the site response in the middle of the valley through the analysis of the earthquakes recorded by the accelerometric station IT.CSA (belonging to the Italian Civil Protection) and the corresponding recordings of the nearby rock station IT.ASS.

In this work, the amount of PE contained in complex biodegradable polymer blends and in carrier bags claimed to be compostable was determined by thermogravimetry analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Since February 2016, the method has been regularly applied and further extended to check the presence of PE in more than 60 carrier bags certified as compostable and has contributed to reveal the incidence of illegal carrier bags on the market. Analyses were commissioned by Legambiente, private companies and laboratories.

Co-seismic changes in groundwater regime are often observed after moderate to strong earthquakes. The 24 August 2016 Mw 6.0 extensional Amatrice earthquake, which was the first event of a long-lasting seismic sequence, including the 30 October 2016 Mw 6.5 Norcia event, triggered a significant discharge alteration to the Pescara di Arquata spring, located in the Umbria-Marche Apennines (Northern Apennines, Central Italy) and exploited for drinking purposes. During the first five months after the first mainshock, an extra flow of about 30% was recorded, while both water chemistry and temperature did not show significant changes. Thereafter, the spring discharge decreased significantly, and at the end of 2019 it was still lower than normal. The Standardized Precipitation Index (SPI) indicates that these low mean monthly discharge values are not related to particularly dry conditions. The increase in post-seismic depletion coefficients indicates that the aquifer empties faster than it did during the inter-seismic period. The observed transient increase and subsequent decrease of discharge are consistent with a transient, earthquake-related increase in hydraulic conductivity.

In this paper, the amount of polyethylene (PE) contained in complex biodegradable polymer blends and in carrier bags claimed to be compostable was determined by thermogravimetry analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). To validate the method, polymer blends based on polylactide (PLA), poly(butylene adipate-co-butylene terephthalate) 53/47 (PBAT), native starch (NS), and calcium carbonate, with known amount of PE ranging from 0 to 10%, were prepared by melt mixing. Py-GC/MS parameters were optimized. In the first step at 400 °C, pyrolysis products originated from thermal cracking of PLA, NS and PBAT were detected. In the second step carried out at 500 °C, triplet peaks characteristic for PE, consisting of α,ω-dienes, α-alkenes and n-alkanes, were revealed together with some signals related to PBAT. TGA under nitrogen atmosphere was used to determine the amount of PE in the blends. An overestimation of about 1.2%, constant for all the blends, was revealed. The overestimation was attributed to the partial overlapping of one of the steps of degradation of the commercial PBAT and that of PE. Additionally, the analytical approach was applied in the characterization of carrier bags claimed to be compostable, recovered directly from the market. The correct determination of the composition of these biodegradable blends is important and crucial to comply with the compostability standard EN 13432-2000. According to this standard, each significant organic constituent of the packaging material must be biodegradable. “Significant” means any constituent present in more than 1% of dry weight of that material. This implies that maximum allowed PE concentration that can be detected in a compostable blend is 1%. In two commercial carrier bags, TGA revealed a component with a degradation temperature of about 455 °C corresponding to that of PE. The relative weight loss percentages of these two carrier bags have been estimated 7.6 and 14%. Optimization of the Py-GC/MS conditions allowed identifying its chemical structure. In fact, the Py-GC/MS at 500 °C provided a pyrogram that was a fingerprint for PE with triplets corresponding to linear chains of α,ω-dienes, α-alkenes and n-alkanes with chain lengths in the range of 9–36 C atoms. Overall, the results show that the combination of TGA and Py-GC/MS can be applied with practical implications.

Subsidence over the last 0.78 myr of a basin in central Italy bounded by a normal fault caused the deactivation and uplift of an Early–Middle Pleistocene alluvial fan at the fault footwall. Uplift of the fan occurred with a basin-bounding fault slip-rate of the order of 0.2 mm a −1 . Subsidence resulted in the reorganization of the river network due to a fall in base level, which triggered headward erosion, stream piracy effects and drainage inversion. The mapped river inversions and catchment piracy were related to the distribution of a quantile regression of 134 alluvial fans v. basin areas. Despite the fact that the two parameters were well fitted by a power law relationship, all the fans corresponding to the captured rivers lay above the regression line (in the fan area field), whereas those corresponding to the capturing rivers were below the regression line (in the basin area field). We propose a general model of alluvial fan growth in active extensional settings that helps to interpret this scatter of fan v. basin area distribution and to identify the most active fault segments. Such an approach can better constrain fault activity in a time window that bridges long-term deformation and the present day deformation inferred from geodesy and/or seismology, increasing our understanding of the steadiness/unsteadiness behaviour of faults.

In this study, we carried out the structural and thermal characterization of a medical-grade poly (lactide) (PLA) by SEC, TGA, DSC, NMR, ICP-MS and Py-GC/MS. Moreover, we investigated the laser-induced degradation occurring when ultrashort laser pulses (ULP) were employed to cut extremely thin polymer films prepared by solvent-casting. ULP polymer cutting technology is an interesting manufacturing process for its advantages in potential medical applications. In fact, heat transmission to the region surrounding the cuts is limited, so that the incisions are precise and the effects on the regions around them are small. In this way, the need for post-processing is reduced and ULP cutting becomes interesting for industrial applications. However, degradation induced by ULP may occur and compromise the properties of the polymer samples. To investigate this possibility, portions of PLA films, ultrashort laser cut (ULC) and uncut, were analysed by SEC, DSC, NMR and FTIR. Furthermore, PLA oligomers were studied by ESI-MS. Both SEC and NMR showed a decrease in the molecular weight. FTIR, ESI-MS and NMR spectra revealed the presence of olefin end groups originated from a β-H transfer mechanism, induced by heat and/or light (Norrish II mechanism). Additionally, the inspection of the ESI mass spectra highlighted the cleavage of ester bonds related to the Norrish I type mechanism, undetected by the other techniques.

We present a reconstruction of the central Marche thrust system in the central-northern Adriatic domain aimed at constraining the geometry of the active faults deemed to be potential sources of moderate to large earthquakes in this region and at evaluating their long-term slip rates. This system of contractional structures is associated with fault-propagation folds outcropping along the coast or buried in the offshore that have been active at least since about 3 Myr. The ongoing deformation of the coastal and offshore Marche thrust system is associated with moderate historical and instrumental seismicity and recorded in sedimentary and geomorphic features. In this study, we use subsurface data coming from both published and original sources. These comprise cross-sections, seismic lines, subsurface maps and borehole data to constrain geometrically coherent local 3D geological models, with particular focus on the Pliocene and Pleistocene units. Two sections crossing five main faults and correlative anticlines are extracted to calculate slip rates on the driving thrust faults. Our slip rate calculation procedure includes a) the assessment of the onset time which is based on the sedimentary and structural architecture, b) the decompaction of clastic units where necessary, and c) the restoration of the slip on the fault planes. The assessment of the differential compaction history of clastic rocks eliminates the effects of compaction-induced subsidence which determine unwanted overestimation of slip rates. To restore the displacement along the analyzed structures, we use two different methods on the basis of the deformation style: the fault parallel flow algorithm for faulted horizons and the trishear algorithm for fault-propagation folds. The time of fault onset ranges between 5.3 and 2.2 Myr; overall the average slip rates of the various thrusts are in the range of 0.26–1.35 mm/yr.

The 1997–98 Umbria–Marche earthquake provided a huge amount of good quality seismological data. The geology of the region has been extensively mapped for over a century by geologists from all over the world. The subsurface geology is constrained by a set of seismic reflection profiles and deep boreholes, acquired for oil exploration. The earthquake stimulated the acquisition of many other geological and geophysical data-sets (surface ruptures, structural analysis, geodetic data, geoeletrical data, etc.). As a consequence, the 1997–98 earthquake is one of the best case studies in the world for extensional earthquakes, driving the possibility of building up an integrated model of an extensional system. We use this favourable test-site to discuss the possibility of integrating and connecting the “seismological” faults (i.e. the short term, instantaneous ruptures generated during the earthquakes, representing the effect of a single event) and the “geological faults” (i.e. the long-term, active faults, exposed at the surface, that are the effects of multiple repeated events of faulting). The review of this complex data-set points to an integrated model, where the moderate seismicity of the region is driven by SW-dipping normal faults, whose dip changes with depth, from 60°–70° (the fault surfaces mapped at the surface), to 35°–45° (the fault segments ruptured during the earthquake, at depths of 2–8 km), to less than 20° at depth > 8 km. These normal faults are not inherited from previous tectonic events. However, the pre-existing arc-shaped compressional structures act as barriers segmenting the extensional fault system. The depth and thickness of the seismogenic layer is lithologically controlled, since the seismicity is confined within the sedimentary cover and do not penetrate the underlying basement. The mainshocks are located close to the bottom of the seismogenic layer, within the Triassic evaporites.

Purificazione di soluzioni a base di silicato di sodio e caratterizzazione di scarti di produzione contenenti piombo tramite SEM-EDX e ICP-MS.

Seismic reflection data are used to reconstruct the subsurface geologic structures below the Umbria-Marche region in Italy, a highly seismogenic area with a recent history of seismic activity (the 1997–1998 Colfiorito sequence). We reprocess three vibroseis seismic profiles (acquired in the early 1980s for hydrocarbon exploration) whose stacked sections were optimized for relatively deep oil targets. On the reprocessed seismic profile closest to the epicentral area, we construct the main reflectors to a depth of about 4 s (two-way time) and compare this interpretation with the available hypocenters of the 1997 earthquakes. The improvements in visualizing the shallow and deep reflections provide a better correlation between the reflectors and the observed surface structures as well as a better delineation of the basement-rock geometry. We find that part of the Colfiorito sequence is localized around some of the reflectors in the reflection profile, which we interpret as related to the active normal faults that outcrop at the surface.

The April 3, 1998 Mw = 5.1 Gualdo Tadino earthquake (central Italy) was the last significant event in the 6-month-long Umbria–Marche seismic crisis. This event and its aftershocks occurred in an area where active faulting produces no striking geological and geomorphological effects. In this study, we investigated the ruptured fault using detailed seismological data and a re-processed and re-interpreted seismic reflection profile. Aftershock location and focal mechanisms were used to constrain the geometry and kinematics of the ruptured fault and a comparison was made with the subsurface image provided by the seismic profile. We found that the 1998 Gualdo Tadino earthquake occurred on a WSW-dipping, normal fault, with a length of about 8 km and a relatively gentle dip (30°–40°), confined between 3.5 and 7 km in depth. Kinematics of the mainshock and aftershocks revealed a NE-trending extension, in agreement with the regional stress field active in the Northern Apennines belt. The Mw = 5.1 earthquake originated above the top of the basement and ruptured within the sedimentary cover, which consists of an evaporites–carbonates multilayer. We hypothesised that the active fault does not reach the surface (blind normal fault).

Normal faults within orogenic belts can be pre-, syn- or post-orogenic features. We studied the Gubbio normal fault (central Italy), which is an example of a pre-orogenic fault reactivated in a post-orogenic stage. The Gubbio Fault is a 22-km-long fault bordering a Quaternary basin and part of an active faults system in the Umbria–Marche region (Central Italy). The interpretation of a set of seismic profiles enables us to reconstruct the fault geometry in detail and to measure displacement and throw distributions along the fault strike. Seismic data indicate that the Gubbio Fault represents an example of multiple reactivation: at least a portion of the fault was active in the Miocene and only a part of the total displacement was achieved in the Quaternary. The reconstruction of the fault geometry at depth shows that the fault is characterised by listric geometry. The fault is also characterised by a bend along strike and structure contours show that this geometry is maintained at depth. As the fault is commonly addressed as presently active, the maximum fault dimensions are correlated to the maximum expected earthquake, and the presence of the fault bend is discussed as a possible barrier to seismic ruptures propagation.

A multi-method approach (palaeothermal and thermochronological analyses; thermal modelling) is applied to reconstruct the exhumation history of the Altotiberina Fault (ATF), a representative example of crustal-scale active low-angle normal faulting in the Northern Apennines (Italy). Thermal maturity and thermochronological data yield similar burial histories but different exhumation patterns for the sedimentary successions in the hangingwall and the footwall of the ATF. Since 3.8 Ma, the ATF footwall has exhumed at rates of 0.90 mm a-1. Exhumation led to bending and deactivation of the ATF uppermost portion as a result of tectonic unloading and isostatic adjustment, followed by migration of extension and the development of a set of domino-like, east-dipping normal faults, rooting on the buried portion of the ATF. ATF activity and isostatic rebound exhumed Triassic rock units from depths of about 4 km. We suggest that isostatic instability is accommodated at shallow crustal levels, in a similar way to what is observed on larger structures at mid-low crustal levels.

The availability of multidisciplinary and high-resolution data is a fundamental requirement to understand the physics of earthquakes and faulting. We present the Alto Tiberina Near Fault Observatory (TABOO), a research infrastructure devoted to studying preparatory processes, slow and fast deformation along a fault system located in the upper Tiber Valley (northern Apennines), dominated by a 60 km long low-angle normal fault (Alto Tiberina, ATF) active since the Quaternary. TABOO consists of 50 permanent seismic stations covering an area of 120 × 120 km2. The surface seismic stations are equipped with 3-components seismometers, one third of them hosting accelerometers. We instrumented three shallow (250 m) boreholes with seismometers, creating a 3-dimensional antenna for studying micro-earthquakes sources (detection threshold is ML 0.5) and detecting transient signals. 24 of these sites are equipped with continuous geodetic GPS, forming two transects across the fault system. Geochemical and electromagnetic stations have been also deployed in the study area. In 36 months TABOO recorded 19,422 events with ML ≤ 3.8 corresponding to 23.36e-04 events per day per squared kilometres; one of the highest seismicity rate value observed in Italy. Seismicity distribution images the geometry of the ATF and its antithetic/synthetic structures located in the hanging-wall. TABOO can allow us to understand the seismogenic potential of the ATF and therefore contribute to the seismic hazard assessment of the area. The collected information on the geometry and deformation style of the fault will be used to elaborate ground shaking scenarios adopting diverse slip distributions and rupture directivity models.

In areas undergoing extensional faulting, the investigation of the tectono-sedimentary evolution of fault-controlled basins through the analysis of morpho-structural features can provide valuable information on the space-time evolution of the active deformation. To this extent, remote sensing data provide a precious source of information that can successfully integrate traditionally collected field data. In this work, we focus on the Montefalco ridge, which topographically separates the Gualdo Cattaneo and Foligno valleys and which represents an inversion of relief being composed of fluvial sands of conglomerates now uplifted more than 200 m above the present day alluvial plain. We carried out a systematic aerial photo-interpretation of two sets of aerial photographs, one flown in 1977 (colour) and one flown in 1997 (black and white). We collected a set of photo-geological data, including Quaternary faults, bedding traces (i.e. the intersection lines between the geological bedding and the topographical surface), and lithological boundaries. Data were transferred to obtain a 1:10,000 scale map. All the aerial photographs were orthorectified to reduce mapping errors when transferring information from the aerial photographs to the topographic base map. In particular, we exploited the i.ortho.photo tool of GRASS GIS, using as data in input a 1m resolution orthophoto taken in 2006 and available as WMS service on the National Cartographic Portal, and a 10m resolution DEM. We then used the GRASS GIS tool geobed.py (http://geomorphology.irpi.cnr.it/tools/gis-and-interpretation-of-aerial-photographs/geobed.py/view) to obtain the bedding attitude starting from the bedding traces and the 10m resolution DEM. Using the same approach we also obtained the attitude of the fault planes. We carried out field checks to validate the photo-geological information. Our results show that aerial photo-interpretation overcomes the main limitations of the traditional field mapping approach since it allows collecting spatially distributed information on fault planes and bedding attitude. The integration of the traditional field structural geology approach and the photo-geological information provides a more complete dataset, which allows making inferences on the tectono-stratigraphic evolution and deformation pattern of the studied basin. We believe this approach can have several other applications in geosciences, such as slope stability analyses, validation of geological profiles, exploration geology, and morpho-tectonic studies.

We present a geomorphological analysis of the recent extensional tectonics of a Quaternary continental basin in the Northern Apennines (Italy). The study area is focused on Upper Tiber Valley (UTV), a basin elongated for 70 km in NNW-SSE direction hosting the Tiber River. The area is characterized by a series of features that make it an excellent case study: (i) homogeneity of lithology (ii) active faults, and (iii) strong morphogenetic activity. In this study, 36 hydrographical basins, tributaries of Tiber River, have been analysed. A preliminary qualitative geomorphological setting was outlined pointing out that the drainage river network shows meaningful evidence of tectonic control, such as abrupt changes in stream directions, knickpoints and steepness anomalies alignments along meaningful length in adjacent basins. Besides, the tectonic control is well marked in base level changes and consequent tectonically induced downcutting. Signs of neotectonics are highlighted by structural landforms too. The entrenchment of alluvial fans, the triangular facets and the fault planes are mapped by field survey and aerial photo interpretation. In addition, a quantitative analysis was also performed. Linear, areal and volumetric indexes related to drainage basins and river networks are taken into account. The geometry of the escarpments delimiting the basin and the landforms detected along the adjacent piedmont are investigated. The ranges of values, according to the existing literature, confirm a condition of wide-ranging morphological disturbance. In the central part of the study area, while the western basins are almost in equilibrium, the eastern ones reveal clear signs of disequilibrium, this is particularly evident along the distal segment of the river network. These data, joined with the characteristics of the escarpment and piedmont junction, confirm that the neotectonic activity, in the centre and in the eastern side of the basin, is the main factor controlling the morphological system.

Storage of CO 2 and, in particular, geological storage is one of the most promising solutions to counteract the continued increase of anthropogenic greenhouse-gas emissions. Here we present a multidisciplinary study of a natural CO 2 geologic reservoir where fluid overpressure, measured at 85% of the lithostatic load, is trapped at ∼4700 m depth in the Northern Apennines of Italy. Deep borehole data and seismic reflection profiles show that the observed CO 2 overpressure: (a) is hosted in dome shaped structures that are the result of the interplay between the compressional and extensional tectonic phases of the area and (b) occurs within dolostones that are sealed by Ca-sulphates (anhydrites) horizons. Field studies on outcropping evaporites, that represent exhumed analogues of the lithologies found at depth in the pressurized reservoir, show dolostones affected by fracturing and faulting and Ca-sulphates characterized by ductile folding without macroscopic fractures. Borehole and laboratory P-wave velocities coincide for anhydrites (6.2–6.3 km/s) but are different for dolostones (6.2–6.3 km/s in situ and ∼7.2 km/s in lab), confirming the different mode of deformation in the two rock types. Since anhydrites are not dominated by fractures, the very low permeability values, ∼10 −19 to ∼10 −22 m 2 , recorded in laboratory experiments, can also be representative for in situ conditions. These data confirm the sealing ability of the anhydrites also for high values of fluid pressure. The integration of these datasets suggests that: (1) tectonics and structural position, and (2) lithology and associated mode of deformation, play a key role for channelling and trapping deep-seated CO 2 -rich crustal fluids.

[1] Broad geological and geophysical documentation is available on regional extensional systems driven by low-angle normal faults. However, little information exists about the three-dimensional geometry and the offset distribution of such extensional structures. We present a new set of balanced geological sections across the extensional fault system driven by the Altotiberina low-angle normal fault in the Northern Apennines of Italy. We document this extensional system throughout a large set of surface (field surveys and geological maps) and subsurface data (seismic reflection profiles and boreholes). The subsurface data allowed us to define the fault deep geometry and to obtain its structural contours. The fault geometry is characterized by both along-dip and along-strike irregularities. In cross-section, the fault displays a staircase trajectory with the shallowest part being dome-shaped and flattened to horizontal. This bending could be due to the footwall uplift triggered by a footwall uploading greater than about 115 MPa. The sequential restoration of five geological cross-sections yields a maximum extension of about 10 km accumulated over approximately 3 Ma. The resulting long-term slip-rate is about 3 mm/yr, which is of the same order as the present-day extensional rate measured by GPS (2.5–3.0 mm/yr), suggesting an almost steady state extension over the last 3 Ma. The distribution of the extension values along the fault strike is bell-shaped, as expected for a continuous surface.

[1] We reconstruct the subsurface geology in a region of the northern Apennines (central Italy) where a protracted extensional sequence occurred in 1997–1998 with maximum magnitude M = 6.0. Our study is mainly based on the interpretation of three reprocessed seismic reflection profiles crossing the epicentral area, which constrain the subsurface geometry to a depth of about 12 km where most of the shallow seismicity occurs. Comparing the subsurface setting with accurately determined earthquake locations, we find that the seismicity is located entirely within the sedimentary cover and does not penetrate the underlying basement. This is explained by considering that the sedimentary cover is rather thick and composed of relatively strong lithologies (platform carbonates and evaporites), while the upper part of the basement consists of weak phyllites and siliciclastic rocks. This weak horizon is also evidenced by the low-Vp values measured in deep wells of the region. Its effect is to decouple the sedimentary cover from the crystalline basement, where only microseismicity occurs. Our study indicates that local structure and stratigraphy can significantly influence the distribution of seismicity within the upper crust, particularly in complex geological environments such as thrust-and-fold belts.

Foreland (early-orogenic) and hinterland (late-orogenic) extensional domains have been widely documented in the Northern Apennines, where they are synchronous with contraction in the active part of the fold and thrust belt. The progressive eastward migration of the contractional front and the associated hinterland extensional field implies that early-orogenic extensional structures, developed in the foreland domains, may experience reactivation/inversion. We present new field data, integrated with seismic evidence, from the Gubbio normal fault, a 22 km long presently active fault, showing: a) evidence for early-orogenic extension since the Lower Miocene time; b) successive positive inversion during the Upper Miocene contraction; and c) renewed, late-orogenic, extension during the Quaternary age. Field data allowed two systems of mesoscale normal faults, respectively interpreted as early- and late-orogenic structures, to be recognised. Stress fields associated with contractional and early- late-orogenic extensional tectonic regimes, are characterised by an overall coaxiality, with directions of compression and tension consistently aligned NE-SW. The symmetry between the successive deformation stages is interpreted as a likely cause for the repeated reactivation of the Gubbio fault since the Miocene. Our analysis in the Gubbio area shows that normal faults play a key role during the evolution of a fold and thrust belt from the early-orogenic stages, when they influence the geometry and evolution of foredeep basins, to the late-orogenic stages when Quaternary activity, due to extension reactivation, controls the evolution of the intramountain basins.

[1] The northern Apennines of Italy are characterized by a complex Tertiary tectonic history, where superposed compressional and extensional deformation occurred. In such regions, characterized by low active extensional strain rate, the coseismic surface ruptures are rare and often a matter of much debate resulting in a difficult connection between “geological” faults (i.e., faults which can be mapped at the surface) and “seismological” faults (i.e., faults which actually generate earthquakes). The availability of detailed geological mapping and high-resolution seismological data for the Colfiorito area, struck in 1997 by a sequence of six 5 < Mw ≤ 6 normal faulting earthquakes, allow us to compare and verify the existence of geometric and kinematic correspondence between the mapped geological Quaternary faults and the activated structures. In map view, the earthquakes distribution reflects the fault pattern mapped at the surface, the length of activated and mapped faults is quite similar (7–10 km), the coseismic subsided region imaged by interferometric synthetic aperture radar data, is located in the hanging wall of the mapped normal faults that bound the Quaternary basins. In section view, there is a geometric connection between mapped normal faults and the aftershock alignments used to image fault geometry at depth. Comparison of striated fault planes and aftershock focal mechanism solutions show a strong kinematic consistency. This study points out that the Quaternary tectonosedimentary evolution and the present-day geological and geomorphologic setting of the Colfiorito area can be interpreted as the result of repeated, extensional earthquakes, similar to the 1997 events, occurring on NW-SE trending normal faults. Our data also show that the main shocks of the Colfiorito sequence nucleated close to the intersections between the normal faults and the preexisting compressional/transpressional structures, which in 1997 acted as lateral barriers to rupture propagation and consequently constrained the fault size.

Nowadays easy accessibility to Information Technologies through Internet and the availability of satellite positioning systems discloses new perspective to geological survey and mapping procedures. The GNU project together with Linux kernel has made available a completely free operating system together with development facilities. This leads researchers to participate actively to software development, sometimes being developers themselves or by funding the development of Free Software. The freedom to use, distribute, study, and modify the software makes it possible to use and adapt to specific geological requirements the leading generic Geographical Information System (GIS) and mapping projects as the Geographic Resources Support System (GRASS GIS) and the Generic Mapping Tools (GMT). Our contribution presents a complete workflow focused on geological mapping activity: from survey to processing/visualization to print-ready map-making. A structural geology mapping and a riverbed-alluvial plain system morpho-sedimentary mapping are presented to test the suitableness of the chosen working environment. In this way, we are forced to abstract specific needs from general requirements. Field survey activities have been carried out with the aid of a Global Positioning System (GPS) receiver and a Personal Digital Assistant (PDA) device put together in a free GPS/PDA software that associates geological data and observations with their respective geographical position. Also, digital camera shots have been geographically registered through EXIF IFD tags and included in the survey databases. Statistical analysis has been done directly on surveyed data inside the geographical/geological database using the R statistical analysis package, avoiding import/export procedures. Finally, print-ready maps have been produced. Correct letter signs, colors, and symbols are used to produce congruous maps. LaTeX typesetting language has been used for detailed, congruous, and well-typeset legends. The use of Free Software gives direct control over every step of the process. In this way we have a solid base to develop features we need and, whenever more efficient new solutions are available, we are able to implement them in the working environment without needing to change the whole. This work, done with the intensive use of Information Technologies, is firmly scientist-centered so that software conforms to the research process and not vice-versa.