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Nanocomposite materials based on commercial thermoplastic polyurethane (TPU) loaded with exfoliated graphite (EG) in concentration between 0 and 20 wt.% have been prepared with EG via melt mixing and compression molding. The materials’ electromagnetic properties have been measured with wave-guide technique between 8.2 and 12.3 GHz. They had shown a clear proportional dependence of complex permittivity with EG content. Above 16 wt.% permittivity becomes frequency dependent. These results are discussed in view of material microstructure by means of scanning electron microscope (SEM) observations. Samples, with 20 wt.% EG and 4 mm thick, show an average value of −20 dB of shielding effectiveness (SE), which make them suitable as shielding material for commercial application. Simulations of metal backed configuration showed that important narrowband EM absorption (>−15 dB) can be achieved at 1 mm thickness, while multilayer structures are necessary to obtain EM broadband absorption (>−10 dB between 8.5 and 12 GHz) can be achieved in 6 mm thick samples. [ABSTRACT FROM AUTHOR]

Abstract: Iso-Kinematic maps have been derived from spatial statistics (Hot Spot and geostatistical analysis) of Permanent Scatterers Interferometric Synthetic Aperture Radar (PS-InSAR) data, and compared with geological, geomorphological, seismological and GPS data in order to analyse the current tectonics and the crustal mobility, at the boundary between the Cottian Alps and the Western Po Plain. This area corresponds to the subsurface junction between the Western Alpine chain and the Northern Apennines. PS data show that the Western Alps are currently uplifting with respect to the adjoining Western Po Plain, as confirmed by the GPS data. The Iso-Kinematic Boundary between these two sectors partly coincides with a regional N–S fault system developed along the inner seismogenic border of the Cottian Alps. Focal mechanisms indicate transpressive movements along this Iso-Kinematic Boundary, which separates two domains characterized by different fault geometry and kinematics, namely: (a) the Cottian Alps, where N–S transtensive/normal faults have developed, and (b) the subsurface Western Po Plain, where NW–SE transpressive/reverse faults are dominant. This articulated tectonic setting results from the complex strain partitioning of the oblique convergence between the European and Adria plates, which is still ongoing, as indicated by seismotectonic and geodetic data. [Copyright &y& Elsevier]

Peridotite clasts in a marine Miocene conglomerate from the Torino Hill (NW Italy) are characterised by an isopachous serpentinized external rim (4–12 mm thick) made up of lizardite, surrounding a non-serpentinized peridotite core. This peculiar structure indicates a diagenetic, post-depositional serpentinization of the peridotite clasts. The conglomerate is cemented by a rim of lizardite, followed by Mg-calcite and Ca-dolomite spar. The burial history of the host sedimentary succession indicates that serpentinization and precipitation of lizardite cements probably occurred at very low temperature (max. 50–60 °C). This is the first reported case of diagenetic, very low temperature serpentinization affecting ultramafite clasts in sedimentary successions. [Display omitted] • Peridotite pebbles/cobbles with serpentinized rim (lizardite) in a Miocene conglomerate. • Conglomerate is cemented by lizardite rims, followed by Mg-rich carbonates. • Rim serpentinization is post-depositional. • Geological evolution indicates a maximum burial depth of 1500 m, corresponding to 50–60 °C. • Low-temperature, diagenetic serpentinization of peridotite clasts. [ABSTRACT FROM AUTHOR]

Abstract: The southern Alpine Foreland basin succession (Late Eocene–Early Oligocene?) lies over the Mesozoic condensed carbonate succession of the Provençal Dauphinois Domain, ends with a chaotic complex, and is overthrust by more internal Alpine units (San Remo–Monte Saccarello Ligurian unit) emplaced in Late Oligocene–Early Miocene times. The chaotic complex consists of debris flow paraconglomerates, breccias, and megablocks, up to km-sized. Despite the post-Eocene Alpine tectonics overprint, particularly intense in its uppermost part, the sedimentary origin of the chaotic complex is proved by the interbedding of paraconglomerates and breccias with fine-grained turbidites. Megablocks consist both of formations buried below the chaotic deposits (Mesozoic Provençal Dauphinois succession, Eocene Alpine Foreland basin succession) both of exotic units (Ligurian Helminthoides Flysch). Paraconglomerate and breccia clasts were sourced by the penecontemporaneous turbidite sands and muds as well as the same lithologies as megablocks. All these features suggest the activity of early Alpine Eocene strike-slip or transtensive fault systems that juxtaposed and exhumed the Helminthoides Flysch unit and the Provençal Dauphinois succession. Submarine ridges were generated and favored rock fall phenomena that involved both small, mm- to dm-sized, clasts and huge slabs detached from the main rock masses. These morphostructural highs were flanked by oversteepened slopes affected by failures that gave rise to debris flows, involving hemipelagic muds and turbidite sands and lithified fragments of older formations, which resulted in strongly polygenic paraconglomerates. The studied mélange is thus fully due to sedimentary processes that were, however, completely controlled by early Alpine tectonics. [Copyright &y& Elsevier]