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This study aims at evaluating the control exerted by fracture stratigraphy and diagenetic processes on oil first migration through an outcropping, mixed carbonate-siliciclastic succession. The present work included results of sedimentological, paleontological, mineralogical, petrographic, structural, and microstructural analyses carried out on organic-rich shales exposed at the Favignana Island of Sicily, Italy. The analyses focus on Upper Triassic yellowish siltstones and greyish laminated dolomitic limestones, which form a 10's of m-thick succession exposed along the westernmost portion of the Sicilian fold-and-thrust belt. The studied succession deposited in a coastal lagoon associated to a wide carbonate platform, in which anoxic bottom conditions allowed the preservation of the organic matter forming catagenetic patches and veins/fractures infill. In fact, two orthogonal fracture sets perpendicular to bedding are pervaded by organic matter. They are hence interpreted as structural elements that affected the paleofluid circulation and oil migration within the Triassic source rock. These two orthogonal sets form the background fracture network predating the formation of three other sets infilled mainly with calcite cements. The latest fracture set also includes barite cements implying a hydrothermal origin (

The results of an integrated stratigraphic, structural, geophysical, and geochemical study reveal the presence of a crustal discontinuity in western Sicily that, at present, runs roughly N-S along a band from San Vito Lo Capo to Sciacca (SVCS). The boundary between the two zones of this discontinuity is nearly orthogonal to the main thrust propagation of the Sicilian thrust-and-fold belt. The different Permian to Tertiary sedimentary evolution recorded by the two zones appears related to this discontinuity, with thick carbonate platforms in the western sector facing deep-water successions in the eastern one. The presence of Upper Triassic reefs, huge megabreccias bodies, and widespread submarine volcanisms along the transition zone suggest the presence of a long lasting weakness zone. This zone has been reactivated episodically as transpressional and/or transtensional faults in relation to the different geodynamic stress acting in central Mediterranean area in different epochs. We speculate that this transition zone has represented a segment of the passive margin of the Ionian Tethys. During the Maghrebian convergence a different style of deformation has affected the two sectors floored by different sedimentary multilayers. The orthogonal-to-oblique differential convergence between the two sectors has resulted in right-lateral transpressional motions, leading to oblique thrusting of deep-water-derived thrusts onto platform-derived thrusts associated with clockwise rotations. The oblique convergence is still ongoing as demonstrated by the seismicity of the area, by the geothermal field with high mantle-derived helium fluxes and by the GPS measurements collected by different authors.

Three main sets of deformation bands are identified in the Lower Pleistocene carbonate grainstones of Favignana Island (Italy). A bedding-parallel set is interpreted to contain compaction bands, based on the lack of evidence for shear. The other two sets are oriented at a high-angle to bedding, forming a conjugate pair comprised of compactive strike-slip shear bands. In this study, we focus on the compactive shear bands documenting their development, as well as analyzing their dimensional parameters and scaling relationships. Single compactive shear bands are thin, tabular zones with porosity less than the surrounding host rocks, and have thicknesses and displacements on the order of a few mm. The growth process for these structures involves localizing further deformation within zones of closely-spaced compactive shear bands and, possibly, along continuous slip surfaces within fault rocks overprinting older zones of bands. During growth, single bands, zones of bands and faults can interact and link, producing larger structures. The transitions from one growth step to another, which are controlled by changes in the deformation behavior (i.e. banding vs. faulting), are recorded by different values of the dimensional parameters for the structures (i.e. length, thickness and displacement). These transitions are also reflected by the ratios and distributions of the dimensional parameters. Considering the lesser porosity values of the structures with respect to the host rock, the results of this contribution could be helpful for mapping, assessing, and simulating carbonate grainstone reservoirs with similar structures.

We present the results of in situ permeability measurements performed, using a portable field permeameter, on normal and strike-slip fault zones that crosscut high-porosity carbonate grainstones. The measurement sites expose in the Cretaceous Orfento Formation of the Majella Mountain (Abruzzo, Italy), and the Lower Pleistocene deposits of the Favignana Island (Sicily, Italy). Nine small-displacement, compactive shear banding-based fault zones have been tested in the field. The fault offset ranges between 10 and 200 centimeters. The acquired permeability data indicate a two orders of magnitude decrease of porosity and permeability from the host rock to the cataclastic fault cores. A clear dependence of the fluid circulation paths through porous carbonates is therefore inferred at depth due to orientation, density and connectivity of the fault zones. Moreover, this study indicates the key role played by the pore network characteristics (pore dimensions above all) of undeformed host rocks on determining extremely different permeability values of the faulted porous carbonate grainstones. Accordingly, the results presented in this study may be helpful in applications such as geofluids management for improving the forecasting of carbonate reservoir quality and understanding the extent of reservoir compartmentalization.

Many structures produced under one single deformation regime, namely extensional, contractional or strike-slip, exhibit remarkable geometrical analogies when analysed at different scales. By contrast, field examples that illustrate the scale effects on structures resulting from superimposed deformations, which were produced under different tectonic regimes, are rare. Yet the change from contraction to extension is known to occur often in the most thickened portions of the continental crust. The Apennine–Maghrebide fold-and-thrust belt of Sicily shows many examples of post-orogenic extensional deformations. Composite structures, resulting from late normal faults that offset folds and thrusts, are observed at four different scales, from regional to mesoscopic, in the south-western portion of Sicily and in the adjacent Isle of Favignana. The recognized analogies in the geometry of these composite structures may provide a key for the interpretation of the features of regional structures, whose deep geometry is often poorly constrained. Moreover, comparison of normalized displacements accommodated by contractional and extensional faults of different scales indicates that self-similarity is not unique to structures produced under single tectonic regimes.

The Sicilian fold-and-thrust belt is located in the central Mediterranean area, and it represents the south-eastern arcuate segment of the Apennine-Maghrebide orogen. The tectonic evolution of the Sicilian belt is documented after outcrop analysis of small-scale structural features carried out throughout the region. Results are consistent with the following four main deformation stages having affected the study area, from the oldest to the youngest: (i) multilayer weakening; (ii) folding-and-thrusting, (iii) extension, and (iv) renewed thrusting. The first deformation stage included three different substages (layer-parallel shortening, bed-parallel simple shear and fold nucleation), the second one by both thrusting and fold amplification and tightening. The third deformation stage involved re-activation of the pre-existing mechanical discontinuities and formation of low-to-high angle normal faults. Out-of-sequence thrusting postdated the aforementioned extensional stage, and formed the latest orogenic deformation stage that affected the Sicilian belt.

Stratigraphic studies and facies analysis integrated with a new geological and structural survey of the Meso-Cenozoic units outcropping in the Campania–Lucania Apennines, southern Italy, allowed us to restore the palaeogeographic pattern and the tectonic evolution of the chain during Oligo-Miocene times. The southern Apennines are a N150°-striking and NE-verging fold-and-thrust belt mainly derived from the deformation of the African–Apulian passive margin. Four wide belts with different features have been recognized in the chain area. From east to west the following units outcrop: (a) successions characterized by basinal to marginal facies, ranging in age from Cretaceous to Miocene, tectonically lying on Plio-Pleistocene foredeep deposits; (b) successions characterized by shallow-water, basinal and shelf-margin facies, ranging in age from middle Triassic to Miocene (‘Lagonegro units’), overthrust on the previous ones; (c) Triassic to Miocene carbonate platform successions (‘Apenninic platform units’), overthrust on the Lagonegro units; (d) Jurassic–Cretaceous to Miocene deep-water successions (ophiolite-bearing or ‘internal’ units and associated siliciclastic wedges), outcropping along the Tyrrhenian belt and the Calabria–Lucania boundary, overthrust on the Apenninic platform units. All these units tectonically lie on the buried Apulian platform which is covered, at least in the eastern sector of the chain, by Pliocene to Pleistocene foredeep deposits. Stratigraphic patterns of the Cretaceous to lower Miocene Lagonegro successions are coherent with the platform margin ones. Calcareous clastics of the Lagonegro basin are in fact supplied by an adjacent western platform, as inferred by several sedimentological evidences (slump and palaeocurrent directions and decreasing grain size towards the depocentre of the basin). Tectonic relationships among the different units of the chain — with particular emphasis on the Lagonegro and Apenninic platform units of the Lucanian segment — are shown by means of both regional and detailed geological cross-sections. The Lagonegro units constantly underlie the carbonate units originating from detachment and thrusting of the western platform and overlie the eastern (i.e. Apulian) platform. The Lagonegro units show a strong lateral variability of map-scale structures. Dome-and-basin folds are in fact largely observable in the Lucanian Apennine. Further, the belt is widely affected by Plio-Quaternary strike–slip and extensional faults. Yet, excluding the brittle deformation due to Quaternary faulting, the complexity of structural styles seems to result from the Neogene refolding of more ancient structures produced by Oligo-Miocene intraplate deformation. This hypothesis is supported by two independent lines of evidence: the first is the recognition of unconformities between the lower Miocene Numidian sandstone and the underlying Lagonegro successions, at least in the southwestern sectors; the second is that the internal (i.e. western) platform remains undeformed until the early Miocene. Both stratigraphic and structural data suggest an external position of the Meso-Cenozoic Lagonegro basin with regard to the coeval Apenninic platform.

Because of its high seismic hazard the urban area of Oliveri has been subject of first level seismic microzonation. The town develops on a large coastal plain made of mixed fluvial/marine sediments, overlapping a complexly deformed substrate. In order to identify points on the area probably suffering relevant site effects and define a preliminary Vs subsurface model for the first level of microzonation, we performed 23 HVSR measurements. A clustering technique of continuous signals has been used to optimize the calculation of the HVSR curves. 42 reliable peaks of the H/V spectra in the frequency range 0.6–10 Hz have been identified. A second clustering technique has been applied to the set of 42 vectors, containing Cartesian coordinates, central frequency and amplitude of each peak to identify subsets which can be attributed to continuous spatial phenomena. The algorithm has identified three main clusters that cover significant parts of the territory of Oliveri. The HVSR data inversion has been constrained by stratigraphic data of a borehole. To map the trend of the roof of the seismic bedrock, from the complete set of model parameters only the depth of the seismic interface that generates peaks fitting those belonging to two clusters characterized by lower frequency has been extracted. The reconstructed trend of the top of the seismic bedrock highlight its deepening below the mouth of the Elicona Torrent, thus suggesting the possible presence of a buried paleo-valley.

The Sicilian Thrust System (STS) is a south-verging (Africa-verging) fold-and-thrust belt including a Mesozoic-Paleogene sedimentary sequence. This thrust stack owes its origin to the deformation of pre-orogenic strata deposited in different palaeogeographic domains belonging to passive margins of the African plate. The STS was deformed during the Neogene, following the closure of the Tethys Ocean and the continental collision between the Sardo-Corso Block and the North Africa margins. The thrust pile was detached from the underlying basement during the Miocene-Pleistocene. The regional-scale structural setting recognized allows us to reconstruct the tectonic evolution of the STS as follows: I - piggy-back thrusting from the Late Oligocene to the Langhian, inducing the building of the Inner Sicilian Chain (ISC); II - piggy-back thrusting from the Langhian to the Tortonian, inducing the formation of the Middle Sicilian Chain (MSC); III - generalized extensional deformation in the chain-foredeep-foreland system from the Tortonian to the Early Pliocene; IV - a new onset of piggy-back thrusting after the Early Pliocene allowed the building of the Outer Sicilian Chain and out-of sequence thrusting in the previously developed ISC and MSC.

Background Postconditioning (PC) has been suggested to reduce myocardial damage during primary percutaneous coronary intervention (PPCI), nevertheless clinical experience is limited. We aimed to explore the cardioprotective effect of PC using cardiac magnetic resonance (CMR) in ST-elevation myocardial infarction (STEMI) patients treated by PPCI. Methods A total of 78 patients with first STEMI (aged 59±12years) referred for PPCI, were stratified for STEMI location and randomly assigned to conventional PPCI or PPCI with PC. All patients, with occluded infarct related artery and no collateral circulation, received abciximab intravenously before PPCI. After reperfusion by effective direct stenting, control subjects underwent no further intervention, while in treated patients PC was performed within 1min of reflow by 4 cycles of 1-minute inflation and 1-minute deflation of the angioplasty balloon. Primary end-point was infarct size (IS) reduction, expressed as percentage of left ventricle mass assessed by delayed enhancement on CMR at 30±10days after index PPCI. Results All baseline characteristics but diabetes (p=0.06) were balanced between groups. Postconditioning patients trended toward a larger IS compared to those treated by standard PPCI (20±12% vs 14±10%, p=0.054). After exclusion of diabetics, PC group still showed a trend to larger IS (p=0.116). Major adverse events seem to be more frequent in PC group irrespective to diabetic status (p=0.053 and p=0.080, respectively). Conclusions This prospective, randomized trial suggests that PC did not have the expected cardioprotective effect and on the contrary it might harm STEMI patients treated by PPCI plus abciximab. ( Clinical Trial Registration -unique identifier: NCT01004289).

Two types of large, branched structures from the Lower Pleistocene (Calabrian) high-energy calcarenites of Favignana Island are described: Faviradixus robustus gen. et sp. nov. and Egadiradixus rectibrachiatus gen. et sp. nov. They may be interpreted as root structures of large plants, trees and trees or shrubs, respectively. The former taxon co-occurs with the marine animal trace fossils Ophiomorpha nodosa , Ophiomorpha isp., Thalassinoides isp. and Beaconites isp. The interpretation as root structures although tentative is probable and can be related to short emergence episodes for the formation of E . rectibrachiatus or to longer emergence, responsible for the discontinuity at the base of the overlying Tyrrhenian deposits, for F . robustus . Calcified root mats of smaller plants associated with the Tyrrhenian or younger emergence surfaces are common.

Nella cardiopatia ischemica, il danno finale miocardico evolve in modo plurifattoriale, attraverso una cascata di eventi in cui ad ogni livello patologico (preclinico, danno reversibile, lesione stabilizzata) corrisponde l’applicazione di uno o piu test diagnostici elettrofisiologici, clinico-laboratoristici e di imaging [1]. Nell’ambito della diagnostica per immagini, mentre la tomografia computerizzata (TC) si e andata affermando nello studio del versante coronarico, la risonanza magnetica (RM) ha consolidato la sua posizione nello studio di tutta la gamma delle ripercussioni cardiache gia a partire dal piu precoce evento della cascata ischemica, costituito dall’iniziale compromissione perfusionale sub-endocardica anche latente, proseguendo nella dimostrazione del deficit funzionale, fino alle lesioni stabilizzate ischemiche, dapprima reversibili, e quindi alla necrosi irreversibile [2, 3, 4]. Negli ultimi anni lo sviluppo tecnologico dell’hardware (magneti ad alta omogeneita e gradienti piu potenti e veloci) e del software (sequenze ibride ed imaging parallelo) hanno consentito un imaging cardiaco affidabile allo stato dell’arte, caratterizzato da un’elevata risoluzione temporale, spaziale e di contrasto.

Acute thoracic aortic syndromes encompass a spectrum of emergencies including aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and aneurysm rupture. All these life-threatening conditions require prompt diagnosis and appropriate management. To date multi-detector row Computed Tomography represents a valuable diagnostic tool especially in the emergency setting. This paper focus on the use of multi-detector row Computed Tomography in the evaluation of acute thoracic aortic syndromes and illustrates the key imaging findings related to each disease.

Detailed geological mapping and new stratigraphic and structural data collected in the Lucania area of the southern Apennines allowed us to assess the deformation history of 11 Monte-Corleto Perticara zone, in the High Agri Valley (Lucanian Apennines, southern Italy) where red and green shales (known as Argille Varicolori or Argille scagliose) crop out. Our observations suggest that: (1) 'chaotic' facies within the Argille Varicolori may be attributed to a broken formation generated by overthrusting of Apenninic Platform units onto already deformed Lagonegro basin strata; (2) gravity sliding phenomena at the thrust front enhanced the development of debris flow and the emplacement of olistostromes at distances of up to tens of kilometres from the leading edge of the Apenninic Platform thrust; (3) the above processes probably ended in mid-Miocene time, as suggested by observed structural and stratigraphic relationships among accreted terranes and synorogenic deposits. The evolutionary model envisaged here could also be relevant in other active convergent zones, where seismic and drilling data are sparse, and in subaerial fossil margins where broken formations occur.

Seismogenic fault models and active deformation ones coupled with models of both earthquake rate and earthquake probability were recently used in a time-independent modelling. The integration of models allows to estimates the magnitude, location, and likelihood of potentially damaging earthquake ruptures in regions with high natural seismic hazard. Improvements of these models imply the recognition of the spatial geometry of the larger, active faults, deemed to be the source of the most damaging future earthquakes. However, identifying active faults and calculating their geologic slip rates for deriving earthquake rates are not easy tasks in regions inaccessible to direct field studies like active offshore areas. To improve the ability to define seismogenic fault models and active deformation models in offshore areas, we aim to develop a geophysical/geological method that allows to (a) identify the spatial geometry of active faults and fault systems in coastal areas, and (b) deduce the average long-term slip rates and recurrence interval, displacement per event, and elapsed time since the last event along the fault plane. The approach consists of innovative combination of geological and geophysical dataset, sampling methodology and GIS based on morphometric analysis. Preliminary results of this multidisciplinary approach applied to the coastal area of north Sicily document active deformation in an on-land sector of the Sicilian Maghrebian Chain and in its off-shore prolongation. Here we present results concerning the Palermo-Termini Imerese coastal sector based on a combination of: 1) structural data, 2) high-resolution reflection seismic data, 3) time series of GNSS data of the permanent stations of Palermo, Partinico, Prizzi, and Termini compared to the IGS station of Noto, 4) morphometric analysis of high-resolution digital elevation data for the hydrographic basins of the Oreto, Eleuterio, Milicia, San Leonardo, Torto and Imera Settentrionale rivers, and 5) seismological data. In the area of the Capo Zafferano promontory, Pleistocene conglomerates and grainstones are affected by recent tectonic deformation. In particular, at two sites near the village of Porticello we observed two sets of N-S to NNW-SSE and NE-SW striking deformation bands. Both sets have an almost vertical dip and show mutual cross-cutting relationships, suggesting their contemporaneous development. The N-S to NNW-SSE striking set shows left-lateral strike slip kinematic. At place, the deformation bands affect also Upper Pleistocene (Tyrrhenian) bio-calcarenites. In the off-shore, a number of seismic units, bounded by unconformities, were identified on seismic lines. The unit of inferred late Pleistocene age appears to be folded and faulted. Faults generally have an inclination of ca. 50°, small displacements up to 10 m and are sealed by the unit of inferred post-LGM age. Only a limited number of these faults are observed moving ca. 3 km offshore towards the NE. The average values of the velocity vectors obtained for the Palermo, Partinico, Prizzi, and Termini Imerese stations are 4.55, 2.97, 2.96, and 2.15 mm/yr, respectively. The direction of the velocity vectors for all stations is oriented towards the IGS reference station of Noto. The relative displacements of the Termini Imerese, Partinico and Prizzi stations respect to Palermo station are most equal to 0.5 mm/yr. Also, the directions of vectors suggest a clockwise rotation. The drainage network analysis highlights that the trunk streams of Eleuterio and San Leonardo drainage networks are asymmetric towards SE and the absolute asymmetry are ~ 3 and ~ 2 km, respectively. On the contrary, the trunk streams of the Milicia, Torto and Imera Settentrionale rivers are asymmetric towards W-NW with an asymmetry ranging from 3.5 up to 4 km. The Oreto stream does not show any evidence of lateral shift. Hypsometric analysis shows two types of statistical distributions of elevation classes. The latter have a bi-modal distribution for the Eleuterio, Oreto and Torto basins while uni-modal for the Milicia and San Leonardo basins. Values of the hypsometric integral are ~ 0.4 for the Milicia, San Leonardo and Torto basins, ~ 0.5 for the Eleuterio basin and 0.35 for the Oreto basin. The study area has been struck in the past centuries by several significant earthquakes of I0 ≥ 6. Mainly low-to-moderate magnitude seismicity, instead, occurred in this sector in the more recent times, showing highest earthquake concentration in the Tyrrhenian off-shore of the study area with respect to the onshore sector. To furnish a first constraint on seismogenic sources lying in this area, we performed hypocenter location and focal mechanism computation of the seismicity that occurred in the last thirty years. Then, we jointly evaluated data and information coming from historical seismicity with the results obtained by the geophysical, geological, and seismological analyses performed in order to better characterize the possible seismogenic sources present in the study region.