0000000001010710
AUTHOR
Alessandra Carollo
Misinterpretation caused by 3D effects on 2D Electrical Resistivity Tomography: tests on simple models
Summary The aim of this work is to evaluate the effects of 2D inversion of electrical resistivity data when in presence on 3D structures by testing synthetic and experimental models. Several numerical simulations have been calculated for different resistivity models and 2D datasets were extracted to study and quantify the effects of 2D inversion on 3D structures. Results have been compared with field texts carried out in quarrying sites. The main tests here presented simulates prism-shaped cavities with a square vertical section of 1 × 1 size and a variable lateral extension d, from 1 to infinity (this latter being a 2D tunnel model). Inversion of predicted data show that 2D tomography does…
3D GPR Model in the Military District of San Giacomo Degli Spagnoli (Palermo)
The georadar method was used to try to find some anthropic structures in a large square inside the Carabinieri barracks in the former military complex of San Giacomo degli Spagnoli in Palermo (Italy). These investigations are part of a broader context of a study of the entire area. The purpose of the investigations is to try to understand if under the ground there are the remains of an ancient horse passage that connected the Royal Palace of Palermo with the sea gate of the city. Furthermore, in the Middle Ages, on the site of the present square, there were most likely two churches, which no longer exist, as evidenced by numerous historical testimonies. One of the two, San Giacomo la Mazara…
Georadar Investigations in the Church of San Paolo (San Giacomo Dei Militari, Palermo).
Summary As part of a research project aimed at drawing up a restoration project for the church of San Paolo, the monument was investigated with georadar surveys. The investigations were followed in a targeted manner by archaeological excavations, under the supervision of the Superintendence of Cultural and Environmental Heritage of Palermo. The San Paolo church is located in the oldest part of the city. The geophysical investigations will be useful to identify any pre-existing structures on which the church could be founded. The georadar investigations focused on the central nave and one of the side aisles to identify buried structures and crypts. The data showed several anomalies. One of t…
Multivariate geophysical survey to detect a shallow fault zone in a landfill project area
An integrated analysis of 2D high-resolution shallow seismic refraction tomographies (SRT) and electrical resistivity tomographies (ERT) has been carried out along a slope where the presence of a fault zone was assumed. It was also applied a post-inversion k-means cluster analysis of the P-wave velocity, the density of the seismic rays and the electrical resistivity of the interpretation models. Distribution maps of the cluster in multi-space were built, allowing to better definethe lateral geometry of a NE-SW directed band composed of intensely tectonized carbonate breccias. Finally, the fracturing and kinematic analysis on fault planes observed along the trenches, highlighted systems of l…
Joint interpretation of electrical and seismic data aimed at modelling the foundation soils of the Maredolce monumental complex in Palermo (Italy)
The monumental complex of Maredolce (Palermo) includes an Arab-Norman castle that stands on the banks of an artificial lake carved out of the calcarenitic rock that rests on impermeable clays. The lake was originally filled with water, thanks to the channelling of a spring. Over time, the lowering of the water table and the high hydraulic permeability of the calcarenites have caused the lake to dry up. A project to renovate the monumental complex has recently been launched. It also provides the study of a possible restoration of the original conditions of the lake. To this end, a multidisciplinary geophysical study was carried out to investigate the geotechnical conditions of permeability o…
Multi-disciplinary analysis to construct a crustal model of the Sicily Channel using geological and geophysical techniques (data): impacts on geological hazard
To understand the dynamics of crustal deformation and earthquakes in active orogenic systems, it is essential to have a detailed view of the lithospheric structures in three dimensions (3D). Several studies in the literature explain how 3D visualization can enable the recognition of tectonic structures or to be able to establish connections between intraplate volcanoes (Wu et al., 2016; Lei & Zhao, 2016; Tan et al., 2019). This work aims to define and discretize a 1D-velocity model of the Sicily Channel; create a detailed 3D lithospheric model of the Sicily Channel using a multidisciplinary approach to evaluate the geological hazard elements that affect the Iblean foreland integrating bathy…
Joint interpretation of seismic refraction tomography and electrical resistivity tomography by cluster analysis to detect buried cavities
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 i…
Cluster analysis for cavity detection using seismic refraction and electrical resistivity tomography
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. Distr…