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Abstract: Vertical profiles of aerosol number–size distribution and black carbon (BC) concentration were measured between ground-level and 500m AGL over Milan. A tethered balloon was fitted with an instrumentation package consisting of the newly-developed micro-Aethalometer (microAeth® Model AE51, Magee Scientific, USA), an optical particle counter, and a portable meteorological station. At the same time, PM2.5 samples were collected both at ground-level and at a high altitude sampling site, enabling particle chemical composition to be determined. Vertical profiles and PM2.5 data were collected both within and above the mixing layer. Absorption coefficient (b abs) profiles were calculated from the Aethalometer data: in order to do so, an optical enhancement factor (C), accounting for multiple light-scattering within the filter of the new microAeth® Model AE51, was determined for the first time. The value of this parameter C (2.05±0.03 at λ =880nm) was calculated by comparing the Aethalometer attenuation coefficient and aerosol optical properties determined from OPC data along vertical profiles. Mie calculations were applied to the OPC number–size distribution data, and the aerosol refractive index was calculated using the effective medium approximation applied to aerosol chemical composition. The results compare well with AERONET data. The BC and b abs profiles showed a sharp decrease at the mixing height (MH), and fairly constant values of b abs and BC were found above the MH, representing 17±2% of those values measured within the mixing layer. The BC fraction of aerosol volume was found to be lower above the MH: 48±8% of the corresponding ground-level values. A statistical mean profile was calculated, both for BC and b abs, to better describe their behaviour; the model enabled us to compute their average behaviour as a function of height, thus laying the foundations for valid parametrizations of vertical profile data which can be useful in both remote sensing and climatic studies. [Copyright &y& Elsevier]

Sinkholes linked to cover evaporite karst in urban environments still represent a challenge in terms of their clear identification and mapping considering the rehash and man-made structures. In the present research, we have proposed and tested a methodology to identify the subsiding features through an integrated and non-invasive multi-scale approach combining seismic reflection, PS-InSAR (PSI), leveling and full 3D Ground Penetrating Radar (GPR), and thus overpassing the limits of each method. The analysis was conducted in a small village in the Alta Val Tagliamento Valley (Friuli Venezia Giulia region, NE Italy). Here, sinkholes have been reported for a long time as well as the hazards linked to their presence. Within past years, several houses have been demolished and at present many of them are damaged. The PSI investigation allowed the identification of an area with higher vertical velocities; seismic reflection imagined the covered karst bedrock, identifying three depocenters; leveling data presented a downward displacement comparable with PSI results; 3D GPR, applied here for the first time in the study and characterization of sinkholes, defined shallow sinking features. Combining all the obtained results with accurate field observations, we identified and mapped the highest vulnerable zone. [ABSTRACT FROM AUTHOR]

The analysis of several seismic reflection profiles offshore the Adria plate reveals a complex spatial-temporal distribution of the carbonate platforms, often linked to different conditions of the crustal thicknesses. The "platform sequence", the "platform-to-basin sequence" and the "oceanic sequence" seem to represent the principal paleogeographic domains and are associated with different crustal types which, during the Tertiary age, became the foreland of the southern Apennine/Calabrian Arc and the Dinaric/Hellenic Chain. In this work, we have tried to highlight how these main crustal domains affect recent tectonics in a remarkable way. The migration of the Calabrian Arc and the Hellenic Chain brought about a regional compressive regime, which currently affects the whole crustal thickness of the Adria plate, causing transpression along the main strike-slip systems of the plate, inversion tectonics in the Salento offshore, and underthrusting below the Dinaric front, whereas the external front of the central-southern Apennines does not seem to be active any more. [ABSTRACT FROM AUTHOR]

We have observed a strong seismic reflection, with high attenuation below the event, at a depth of 1700-1800 ms TWT (about 700 m below the sea bottom), above the Apulia carbonate platform, in the Salento Adriatic offshore, Otranto Channel. The Merlo-1 explorative well penetrated the Plio-Pleistocene and Upper Miocene sediments covering a structural high of the Cretaceous-Oligocene units of the platform margin. This position, in our opinion, compromised the possibility of crossing the reflector, terminating in onlap or in pinch-out around the structure drilled by the well. We performed a dedicated signal analysis in order to evaluate if this bright spot effectively represents a gas reservoir. We used seismic attribute analysis considering amplitude, phase and frequency related attributes, velocity analysis and AVO to improve the interpretation and to obtain semi-quantitative data. Interpretation of all the available seismic profiles was used to map the extension of the possible reservoir and its relation to the Apulia platform margins. [ABSTRACT FROM AUTHOR]