On the ability of Moho reflections to affect the ground motion in northeastern Italy: a case study of the 2012 Emilia seismic sequence

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Integrated Geophysical Study of Archaeological Sites in the Aquileia Area

Integrated remote sensing and geophysical methods can provide detailed information about buried cultural heritage. We implemented an integrated survey protocol (IREGA, Integrated REmote-sensing and Geophysical prospecting for Archaeology) and tested the performance of the method in the area of the ancient Roman town of Aquileia, NE Italy, to define and characterize microareas of archaeological interest starting from macro-area observations. We used electromagnetic (GPR; ground-penetrating radar), magnetic and remote sensing (MIVIS; Multispectral Infrared and Visible Imaging Spectrometer) to image and characterize buried targets of potential archaeological interest in the depth range between 100 and 350 cm. We identified various geometrically coherent anomalies, possibly related to subsurface structures, through MIVIS data processing and found them in good agreement with the elements reported in the Aquileia archaeological map obtained from documentary evidence and excavations performed in the last century. Ultra High Resolution (UHR) Multi- Fold (MF) Ground-penetrating Radar (GPR) and magnetic surveys confirmed the MIVIS results and allowed imaging and mapping of buried structure related to different Roman remains (SE sector of the Circus, harbor and residential buildings foundations, roads)

An augmented seismic network to study off-shore seismicity around the Maltese Islands : the FASTMIT experiment

Appropriate planning and deployment of a seismic network is a prerequisite to efficiently monitor seismic activity, determine the seismic source, and eventually contribute to the seismotectonic interpretation and seismic hazard assessment. The evaluation and effectiveness of a local network on the Maltese islands, recently extended by a further six seismic stations for one year, is presented. We investigate the new temporary network's data and site selection quality, utilizing spectral patterns in the seismic data and also evaluate the network's event location performance by relocating a number of recorded events. The results will be signifi cant for the future installation of permanent seismic stations on the Maltese islands.peer-reviewe

Multi-fold Ground Penetrating Radar Imaging and Classification of Buried Targets for Environmental Applications

Abstract We use an integration of Single Fold (SF), Multi fold (MF), i.e. multi offset, Multi Azimuth (MA) and Multi Component (MC) or Polarimetric Ground Penetrating Radar (GPR) configurations to identify, characterize and classify targets of environmental interest. The results obtained in real and controlled conditions are validated by numerical simulations and excavation and show that MF/MA/MC GPR methods are fit for target classification in complex subsurface conditions

Velocity spectra and seismic-signal identification for surface waveanalysis

Rayleigh-wave dispersion is observed every time acoustic impedance stratification occurs, and its analysis is suitable for vertical shear-wave profile reconstruction. Accurate dispersion-curve identification is essential in order to properly determine the shear-wave velocity distribution of a medium.Data sets characterized by several events generate complex velocity spectra that can lead to possible misinterpretations. We analyse a real data set by taking into account theoretical dispersion curves and synthetic data obtained from numerical simulations in order to avoid possible pitfalls that couldarise from the complex trends exhibited in the f\u2013k (frequency\u2013wavenumber) and v\u2013f (velocity\u2013frequency) domains. In the v\u2013f domain in particular, we show that reflection events and their multiples generate coherences that could be misinterpreted because of their similarity to typical higher-modedispersion curves. Another observed signal is interpreted in terms of guided waves and related phenomena. The results of the fundamental-mode dispersion curve inversion performed via genetic algorithms indicate a sedimentary cover stratification that simple reflection analysis cannot reveal.The present case study highlights the importance of a synergic approach, based on integrated synthetic and field data analysis, for correct interpretation of all the wavefield components in thevelocity spectrum