Geophysical methods (in particular ERT technique) constitute an excellent tool for the detection ... more Geophysical methods (in particular ERT technique) constitute an excellent tool for the detection of buried cavities. However the integration approach of e different geophysical methods could minimize the ambiguity of geophysical interpretation of the buried cavity. The technique of electrical tomography has been joined to the technique of seismic refraction tomography in order to obtain more robust interpretations. Many tests have been carried out using synthetic data and experimental ones. It was finally used a statistical approach based on cluster analysis of the P-wave velocity, the density of the seismic rays and the electrical resistivity of the synthetic and experimental models. Distribution maps of the cluster in multi-space were built, allowing to better define and interpret the anomalies of the subsoil
Recently, the use of microtremor techniques for subsoil investigation has increased significantly... more Recently, the use of microtremor techniques for subsoil investigation has increased significantly. The HVSR (Horizontal to Vertical Spectral Ratio) technique allows, in many cases, to obtain a seismo-stratigraphic reconstruction of the subsoil and to identify areas with similar seismic behavior. However, the stratigraphic interpretation of the HVSR peaks still remains a subjective choice and linked to a priori information. A non-hierarchical centroid-based algorithm was modified to group HVSR peaks of different measurements that can be attributed to the same generating seismic discontinuity. Some tests performed have shown that the proposed algorithm produces valid results even in the absence of a priori information to evaluate the choice of the optimal grouping. The results obtained for HVSR measurements acquired in the city of Modica (Italy) are presented. The cluster analysis of these data and the information on the lithologies outcropping in the area made it possible to reconstr...
The church of S. Mary of the Admiral in Palermo, known as “La Martorana” and very famous for its ... more The church of S. Mary of the Admiral in Palermo, known as “La Martorana” and very famous for its Byzantine mosaics, has been a World Heritage site since 2015. The mosaic system of the church includes several groups of figures and scenes from the life of the Virgin Mary. From the western part of the ancient church only two mosaics survive, detached from their original position, and are now located in two internal chapels. On the occasion of several restoration works, these two mosaic panels were investigated with non-invasive techniques, in order to provide diagnostic support to the restoration and consolidation interventions. The investigations were aimed at detecting any air pockets that could cause the detachment of the tesserae or of possible differences between cement mortars under the tesserae. For this purpose, the integrated use of two non-invasive techniques namely infrared thermography (IRT) and ground penetrating radar (GPR) was considered. The joint analysis of IRT and GP...
Misterbianco is located on the southern flank of Mt. Etna (Unesco site), in eastern Sicily (Italy... more Misterbianco is located on the southern flank of Mt. Etna (Unesco site), in eastern Sicily (Italy). This site, also known as Monasterium Album, has a long and tormented history linked with volcanic activity of Mt. Etna and regional seismicity. This site received much attention in the 2000s when excavation works brought to light a 14th century church remains below the thick layer of the 1669 lava. This study documents the first diagnostic multidisciplinary survey performed at this site 350 years after the eruption: the investigations were performed by using techniques such as ground-penetrating radar, infrared thermography, a terrestrial laser scanner and a drone survey to analyze the site’s topography, to adequately map the hidden structures inside the building and to identify fractures and deformations in the church. Starting from the site history, we present the results of the multidisciplinary approach aimed at reconstructing the historical events that led to the damage in the ch...
near surface seismostratigraphic modeLLing of the bandita pLain in paLermo town (itaLy) from inte... more near surface seismostratigraphic modeLLing of the bandita pLain in paLermo town (itaLy) from integrated anaLysis of hvsr and stratigraphic data R. Martorana1, M. Agate1, P. Capizzi1, F. Cavera1, A. D’Alessandro2 1 Dipartimento di Scienze della Terra e del Mare (DiSTeM), Università degli Studi di Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Roma, Italy
MULTIVARIATE MODELLING OF GEOPHYSICAL TOMOGRAPHIC DATA TO IDENTIFY A TECTONIZED AREA P. Capizzi1,... more MULTIVARIATE MODELLING OF GEOPHYSICAL TOMOGRAPHIC DATA TO IDENTIFY A TECTONIZED AREA P. Capizzi1,2, A. Carollo1, M. Gasparo Morticelli1, R. Martorana1,3, A. Sulli1,3 1 Università degli Studi di Palermo, Dipartimento di Scienze della Terra e del Mare (DiSTeM), Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italy 3 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Roma, Italy
An application of HVSR inversion is presented in order to verify the effectiveness of this techni... more An application of HVSR inversion is presented in order to verify the effectiveness of this technique for purposes of reconstruction of the buried geological setting where stratigraphic constraints are available. Specifically, the reconstruction of the stratigraphy in the studied area has been obtained by a seismic-stratigraphic three-dimensional modeling. This allowed for geophysical and geognostic data derived from surveys carried out during this study, as well as previously by the municipality of Palermo.
An integrated research on the hinge zone between northern Sicily and its Tyrrhenian off-shore has... more An integrated research on the hinge zone between northern Sicily and its Tyrrhenian off-shore has been carried out, by means of structural, seismological and statistical analyses. The main structural features of the area are represented by both NWSE to W\u2013E striking right-lateral and N\u2013S to NE-SW striking leftlateral fault systems, responsible of uplifting (restraining) and subsiding (releasing) zones. Within this hinge zone the seismicity is mainly located between 10 and 20 km of depth and clustered according to the orientation of the outcropping fault systems. The brittle strain partitioning related to a right-lateral simple shear zone has been reconstructed in the onshore sector, while in the offshore the structural setting has been inferred from morpho-bathymetric and geological maps of the southern Tyrrhenian basin. Moreover, in this latter zone, a new seismological study has been carried out on a part of 2002 seismic sequence (more than 600 events), using a database obtained by merging the CSI 1.1 catalogue of INGV and new data recorded by 7 three-components stations of a temporary network installed by INGV. These seismic events, occurred between September and December 2002, have been relocated using an eight layered velocity model optimized for the southern Tyrrhenian. The focal mechanisms of 40 events have been determined. The Coulomb stress changes related to the main event have been also calculated. The general geometric characters of the whole set of investigated parameters well fit the simple shear deformational style reconstructed of the onshore study zone. Moreover, both focal mechanisms and principal stress components of about 100 events of 1992-1993 Pollina seismic swarm (Eastern Madonie Mts.) has been also carried out. The main focal mechanisms typologies and stress axis trends show a good agreement with the seismogenic volume anisotropy required by the seismotectonic model. This model is also supported by the high resolution tomographic results of the more shallow structures in the Pollina area, and by the study of two recent minor seismic sequences affecting the northern Sicilian sector (2010-2012) in the Caprileone area (Messina) and in the Isola delle Femmine offshore (west of Palermo). In this last sector high resolution morphobatimetric (multibeam) data highlight the presence of very young morphological features related to the ENE-WSW and NNW-SSE trending structural systems, probably responsible of the recent events
Multidisciplinary geophysical investigations have been carried out in a small area of the Greek a... more Multidisciplinary geophysical investigations have been carried out in a small area of the Greek archaeological site of Kamarina, in southern Sicily, in order to support some hypotheses, derived from historical and archaeological bases. After an aerial photographic and thermographic survey, a small area near to the Agora has been considered for magnetometric and GPR investigations. Obtained results show a good correlation and allow to highlight some structures oriented in agreement with the uncovered remains. The use of integrated geophysical techniques allowed a more robust interpretation of the detected anomalies in order to better address the choices for new excavations
635 gPR AND MAgNETIC SuRvEy AT ThE KAMARINA ARChAEOLOgICAL SITE (SICILy, ITALy) SuPPORTED by AERI... more 635 gPR AND MAgNETIC SuRvEy AT ThE KAMARINA ARChAEOLOgICAL SITE (SICILy, ITALy) SuPPORTED by AERIAL PhOTOgRAPhIC AND ThERMOgRAPhIC DATA R. Martorana1,2, P. Capizzi1, A. D’Alessandro2, A. Pisciotta3, S. Scudero2 1 Dip. di Scienze della Terra e del Mare, Università degli Studi di Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Italy 3 Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Italy
3D Ultrasonic Tomography for non-destructive test and for diagnostic study works of art is a rath... more 3D Ultrasonic Tomography for non-destructive test and for diagnostic study works of art is a rather established methodology. This method allow us to locate, within the volume of work of art, areas of structural non homogeneities, areas of decay, fracture or damaged. This work wants to present some tests carried out to optimize these parameters in order to obtain a better anomaly image resolution for the case history presented. The optimization of these parameters allows locating structural non homogeneity areas, fractures or damages, within the volume, according to shape and type of the investigated anomalies
Introduction. The use of HVSR technique allows in many cases (Bonnefoy-Claudet et al., 2006) to o... more Introduction. The use of HVSR technique allows in many cases (Bonnefoy-Claudet et al., 2006) to obtain detailed reconstruction of the roof of the seismic bedrock (Di Stefano et al., 2014) and to identify areas with similar seismic behaviour. Theoretical considerations (Nakamura, 1989) and experimental tests showed that amplification of horizontal motions between bottom and top of a sedimentary cover is well related to the ratio between the spectra of the horizontal and vertical components of the ground velocity (Nakamura, 2000). This ratio is a measure of ellipticity of Rayleigh wave polarization, overlooking Love and body waves contribution. Assuming that subsoil can be represented as a stack of homogeneous horizontal layers and imposing some geometric and/or physical constraints it is possible to estimate the parameters of the shear wave velocity model (Fäh et al., 2003; Parolai et al., 2000). The integration of data related to HVSR and active techniques based on the analysis of s...
Near Surface Geoscience 2015 - 21st European Meeting of Environmental and Engineering Geophysics, 2015
A systematic comparison is presented between some 2D resistivity models and their images by the i... more A systematic comparison is presented between some 2D resistivity models and their images by the inversion of synthetic datasets relating to three different arrays, suitable for multichannel data acquisitions (dipole-dipole (DD), Wenner-Schlumberger (WS) and multiple gradient (MG)). The goal is to study how the measurement errors affects the resolution of the tomographic models and the ability to retrieve correct information on buried targets. We considered different data acquisition patterns, gradually increasing the complexity of the combinations of potential spacing and dipolar distance. To this end we increased the number of current dipoles to obtain approximately the same amount of measures, increasing the investigation time. Results from noise-free and noisy data are discussed and compared with those from field data. The results show that: the quality of the inversion models, for a fixed noise level, depends significantly on the data acquisition pattern; the information recovery and the resolution, being equal the number of measurements, is overall better for WS and worse for DD; the decrease of sensitivity with depth is lower for particular acquisition patterns that allow to better resolve deeper targets; the MG array can be preferred because it provides comparable results, using a smaller number of current electrodes.
Abstract In the last few years, the geophysical methods of seismic refraction tomography (SRT) an... more Abstract In the last few years, the geophysical methods of seismic refraction tomography (SRT) and electrical resistivity tomography (ERT) are among the most used geophysical techniques for the reconstruction of subsoil geometries, for the investigation of underground cavities and also for the archaeological prospecting. However, the main disadvantage of each geophysical method is the difficulty of final interpretation of the data. In order to eliminate artifacts and generally improve the reliability and accuracy of geophysical interpretation, it is useful to perform a joint approach of different geophysical methods, also introducing the a priori information. In this work, it is shown the integrated study of seismic refraction tomography and electrical resistivity tomography techniques, the two geophysical methods are tested on both synthetic and real data and the integration of data is useful in detecting buried cavities and also evaluate their geometric characteristics. Likelihood parameters has been defined and tested, in order to help recognizing voids from other lithological structures. Finally, a statistical approach based on cluster analysis of the P-wave velocity, the density of the seismic rays and the electrical resistivity of the synthetic and experimental models was used. Multi-space cluster distribution maps were built, allowing to better define and interpret the anomalies of the subsoil.
In recent years, a detailed archeoseismological investigation has been carried out in the necropo... more In recent years, a detailed archeoseismological investigation has been carried out in the necropolis of Abakainon in order to identify traces of an ancient earthquake. Although the identification of seismic damage was undoubtedly attributed to the 1st century AD earthquake, it was hypothesised that the level of damaging observed in the necropolis, as well as the counter slope tilting of the tomb basements may have also caused by a seismo-induced landslide, which produced locally an amplification of the seismic shaking. In order to identify the landslide, on which the Greek site lies, detailed geomorphological and geophysical surveys have been carried out. The research was directed to the acquisition of deep geological data for the reconstruction of slope process and the thickness of mobilised materials. The applied geophysical techniques included Seismic Refraction Tomography (SRT), Electrical Resistivity Tomography (ERT), microtremor analysis (HVSR). The surveys were performed in order to delineate the sliding surface and to assess approximatively the thickness of mobilised materials. The results coming from geomorphological data combined with and geophysical surveys confirm the presence of different overlapped landslides in the studied area.
Geophysical methods (in particular ERT technique) constitute an excellent tool for the detection ... more Geophysical methods (in particular ERT technique) constitute an excellent tool for the detection of buried cavities. However the integration approach of e different geophysical methods could minimize the ambiguity of geophysical interpretation of the buried cavity. The technique of electrical tomography has been joined to the technique of seismic refraction tomography in order to obtain more robust interpretations. Many tests have been carried out using synthetic data and experimental ones. It was finally used a statistical approach based on cluster analysis of the P-wave velocity, the density of the seismic rays and the electrical resistivity of the synthetic and experimental models. Distribution maps of the cluster in multi-space were built, allowing to better define and interpret the anomalies of the subsoil
Recently, the use of microtremor techniques for subsoil investigation has increased significantly... more Recently, the use of microtremor techniques for subsoil investigation has increased significantly. The HVSR (Horizontal to Vertical Spectral Ratio) technique allows, in many cases, to obtain a seismo-stratigraphic reconstruction of the subsoil and to identify areas with similar seismic behavior. However, the stratigraphic interpretation of the HVSR peaks still remains a subjective choice and linked to a priori information. A non-hierarchical centroid-based algorithm was modified to group HVSR peaks of different measurements that can be attributed to the same generating seismic discontinuity. Some tests performed have shown that the proposed algorithm produces valid results even in the absence of a priori information to evaluate the choice of the optimal grouping. The results obtained for HVSR measurements acquired in the city of Modica (Italy) are presented. The cluster analysis of these data and the information on the lithologies outcropping in the area made it possible to reconstr...
The church of S. Mary of the Admiral in Palermo, known as “La Martorana” and very famous for its ... more The church of S. Mary of the Admiral in Palermo, known as “La Martorana” and very famous for its Byzantine mosaics, has been a World Heritage site since 2015. The mosaic system of the church includes several groups of figures and scenes from the life of the Virgin Mary. From the western part of the ancient church only two mosaics survive, detached from their original position, and are now located in two internal chapels. On the occasion of several restoration works, these two mosaic panels were investigated with non-invasive techniques, in order to provide diagnostic support to the restoration and consolidation interventions. The investigations were aimed at detecting any air pockets that could cause the detachment of the tesserae or of possible differences between cement mortars under the tesserae. For this purpose, the integrated use of two non-invasive techniques namely infrared thermography (IRT) and ground penetrating radar (GPR) was considered. The joint analysis of IRT and GP...
Misterbianco is located on the southern flank of Mt. Etna (Unesco site), in eastern Sicily (Italy... more Misterbianco is located on the southern flank of Mt. Etna (Unesco site), in eastern Sicily (Italy). This site, also known as Monasterium Album, has a long and tormented history linked with volcanic activity of Mt. Etna and regional seismicity. This site received much attention in the 2000s when excavation works brought to light a 14th century church remains below the thick layer of the 1669 lava. This study documents the first diagnostic multidisciplinary survey performed at this site 350 years after the eruption: the investigations were performed by using techniques such as ground-penetrating radar, infrared thermography, a terrestrial laser scanner and a drone survey to analyze the site’s topography, to adequately map the hidden structures inside the building and to identify fractures and deformations in the church. Starting from the site history, we present the results of the multidisciplinary approach aimed at reconstructing the historical events that led to the damage in the ch...
near surface seismostratigraphic modeLLing of the bandita pLain in paLermo town (itaLy) from inte... more near surface seismostratigraphic modeLLing of the bandita pLain in paLermo town (itaLy) from integrated anaLysis of hvsr and stratigraphic data R. Martorana1, M. Agate1, P. Capizzi1, F. Cavera1, A. D’Alessandro2 1 Dipartimento di Scienze della Terra e del Mare (DiSTeM), Università degli Studi di Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Roma, Italy
MULTIVARIATE MODELLING OF GEOPHYSICAL TOMOGRAPHIC DATA TO IDENTIFY A TECTONIZED AREA P. Capizzi1,... more MULTIVARIATE MODELLING OF GEOPHYSICAL TOMOGRAPHIC DATA TO IDENTIFY A TECTONIZED AREA P. Capizzi1,2, A. Carollo1, M. Gasparo Morticelli1, R. Martorana1,3, A. Sulli1,3 1 Università degli Studi di Palermo, Dipartimento di Scienze della Terra e del Mare (DiSTeM), Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Sezione Palermo, Palermo, Italy 3 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Roma, Italy
An application of HVSR inversion is presented in order to verify the effectiveness of this techni... more An application of HVSR inversion is presented in order to verify the effectiveness of this technique for purposes of reconstruction of the buried geological setting where stratigraphic constraints are available. Specifically, the reconstruction of the stratigraphy in the studied area has been obtained by a seismic-stratigraphic three-dimensional modeling. This allowed for geophysical and geognostic data derived from surveys carried out during this study, as well as previously by the municipality of Palermo.
An integrated research on the hinge zone between northern Sicily and its Tyrrhenian off-shore has... more An integrated research on the hinge zone between northern Sicily and its Tyrrhenian off-shore has been carried out, by means of structural, seismological and statistical analyses. The main structural features of the area are represented by both NWSE to W\u2013E striking right-lateral and N\u2013S to NE-SW striking leftlateral fault systems, responsible of uplifting (restraining) and subsiding (releasing) zones. Within this hinge zone the seismicity is mainly located between 10 and 20 km of depth and clustered according to the orientation of the outcropping fault systems. The brittle strain partitioning related to a right-lateral simple shear zone has been reconstructed in the onshore sector, while in the offshore the structural setting has been inferred from morpho-bathymetric and geological maps of the southern Tyrrhenian basin. Moreover, in this latter zone, a new seismological study has been carried out on a part of 2002 seismic sequence (more than 600 events), using a database obtained by merging the CSI 1.1 catalogue of INGV and new data recorded by 7 three-components stations of a temporary network installed by INGV. These seismic events, occurred between September and December 2002, have been relocated using an eight layered velocity model optimized for the southern Tyrrhenian. The focal mechanisms of 40 events have been determined. The Coulomb stress changes related to the main event have been also calculated. The general geometric characters of the whole set of investigated parameters well fit the simple shear deformational style reconstructed of the onshore study zone. Moreover, both focal mechanisms and principal stress components of about 100 events of 1992-1993 Pollina seismic swarm (Eastern Madonie Mts.) has been also carried out. The main focal mechanisms typologies and stress axis trends show a good agreement with the seismogenic volume anisotropy required by the seismotectonic model. This model is also supported by the high resolution tomographic results of the more shallow structures in the Pollina area, and by the study of two recent minor seismic sequences affecting the northern Sicilian sector (2010-2012) in the Caprileone area (Messina) and in the Isola delle Femmine offshore (west of Palermo). In this last sector high resolution morphobatimetric (multibeam) data highlight the presence of very young morphological features related to the ENE-WSW and NNW-SSE trending structural systems, probably responsible of the recent events
Multidisciplinary geophysical investigations have been carried out in a small area of the Greek a... more Multidisciplinary geophysical investigations have been carried out in a small area of the Greek archaeological site of Kamarina, in southern Sicily, in order to support some hypotheses, derived from historical and archaeological bases. After an aerial photographic and thermographic survey, a small area near to the Agora has been considered for magnetometric and GPR investigations. Obtained results show a good correlation and allow to highlight some structures oriented in agreement with the uncovered remains. The use of integrated geophysical techniques allowed a more robust interpretation of the detected anomalies in order to better address the choices for new excavations
635 gPR AND MAgNETIC SuRvEy AT ThE KAMARINA ARChAEOLOgICAL SITE (SICILy, ITALy) SuPPORTED by AERI... more 635 gPR AND MAgNETIC SuRvEy AT ThE KAMARINA ARChAEOLOgICAL SITE (SICILy, ITALy) SuPPORTED by AERIAL PhOTOgRAPhIC AND ThERMOgRAPhIC DATA R. Martorana1,2, P. Capizzi1, A. D’Alessandro2, A. Pisciotta3, S. Scudero2 1 Dip. di Scienze della Terra e del Mare, Università degli Studi di Palermo, Italy 2 Istituto Nazionale di Geofisica e Vulcanologia, Centro Nazionale Terremoti, Italy 3 Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Palermo, Italy
3D Ultrasonic Tomography for non-destructive test and for diagnostic study works of art is a rath... more 3D Ultrasonic Tomography for non-destructive test and for diagnostic study works of art is a rather established methodology. This method allow us to locate, within the volume of work of art, areas of structural non homogeneities, areas of decay, fracture or damaged. This work wants to present some tests carried out to optimize these parameters in order to obtain a better anomaly image resolution for the case history presented. The optimization of these parameters allows locating structural non homogeneity areas, fractures or damages, within the volume, according to shape and type of the investigated anomalies
Introduction. The use of HVSR technique allows in many cases (Bonnefoy-Claudet et al., 2006) to o... more Introduction. The use of HVSR technique allows in many cases (Bonnefoy-Claudet et al., 2006) to obtain detailed reconstruction of the roof of the seismic bedrock (Di Stefano et al., 2014) and to identify areas with similar seismic behaviour. Theoretical considerations (Nakamura, 1989) and experimental tests showed that amplification of horizontal motions between bottom and top of a sedimentary cover is well related to the ratio between the spectra of the horizontal and vertical components of the ground velocity (Nakamura, 2000). This ratio is a measure of ellipticity of Rayleigh wave polarization, overlooking Love and body waves contribution. Assuming that subsoil can be represented as a stack of homogeneous horizontal layers and imposing some geometric and/or physical constraints it is possible to estimate the parameters of the shear wave velocity model (Fäh et al., 2003; Parolai et al., 2000). The integration of data related to HVSR and active techniques based on the analysis of s...
Near Surface Geoscience 2015 - 21st European Meeting of Environmental and Engineering Geophysics, 2015
A systematic comparison is presented between some 2D resistivity models and their images by the i... more A systematic comparison is presented between some 2D resistivity models and their images by the inversion of synthetic datasets relating to three different arrays, suitable for multichannel data acquisitions (dipole-dipole (DD), Wenner-Schlumberger (WS) and multiple gradient (MG)). The goal is to study how the measurement errors affects the resolution of the tomographic models and the ability to retrieve correct information on buried targets. We considered different data acquisition patterns, gradually increasing the complexity of the combinations of potential spacing and dipolar distance. To this end we increased the number of current dipoles to obtain approximately the same amount of measures, increasing the investigation time. Results from noise-free and noisy data are discussed and compared with those from field data. The results show that: the quality of the inversion models, for a fixed noise level, depends significantly on the data acquisition pattern; the information recovery and the resolution, being equal the number of measurements, is overall better for WS and worse for DD; the decrease of sensitivity with depth is lower for particular acquisition patterns that allow to better resolve deeper targets; the MG array can be preferred because it provides comparable results, using a smaller number of current electrodes.
Abstract In the last few years, the geophysical methods of seismic refraction tomography (SRT) an... more Abstract In the last few years, the geophysical methods of seismic refraction tomography (SRT) and electrical resistivity tomography (ERT) are among the most used geophysical techniques for the reconstruction of subsoil geometries, for the investigation of underground cavities and also for the archaeological prospecting. However, the main disadvantage of each geophysical method is the difficulty of final interpretation of the data. In order to eliminate artifacts and generally improve the reliability and accuracy of geophysical interpretation, it is useful to perform a joint approach of different geophysical methods, also introducing the a priori information. In this work, it is shown the integrated study of seismic refraction tomography and electrical resistivity tomography techniques, the two geophysical methods are tested on both synthetic and real data and the integration of data is useful in detecting buried cavities and also evaluate their geometric characteristics. Likelihood parameters has been defined and tested, in order to help recognizing voids from other lithological structures. Finally, a statistical approach based on cluster analysis of the P-wave velocity, the density of the seismic rays and the electrical resistivity of the synthetic and experimental models was used. Multi-space cluster distribution maps were built, allowing to better define and interpret the anomalies of the subsoil.
In recent years, a detailed archeoseismological investigation has been carried out in the necropo... more In recent years, a detailed archeoseismological investigation has been carried out in the necropolis of Abakainon in order to identify traces of an ancient earthquake. Although the identification of seismic damage was undoubtedly attributed to the 1st century AD earthquake, it was hypothesised that the level of damaging observed in the necropolis, as well as the counter slope tilting of the tomb basements may have also caused by a seismo-induced landslide, which produced locally an amplification of the seismic shaking. In order to identify the landslide, on which the Greek site lies, detailed geomorphological and geophysical surveys have been carried out. The research was directed to the acquisition of deep geological data for the reconstruction of slope process and the thickness of mobilised materials. The applied geophysical techniques included Seismic Refraction Tomography (SRT), Electrical Resistivity Tomography (ERT), microtremor analysis (HVSR). The surveys were performed in order to delineate the sliding surface and to assess approximatively the thickness of mobilised materials. The results coming from geomorphological data combined with and geophysical surveys confirm the presence of different overlapped landslides in the studied area.
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