Joint interpretation of electrical and seismic data aimed at modelling the foundation soils of the Maredolce monumental complex in Palermo (Italy)

Abstract

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 of the land outcropping and provides valid technical solutions for waterproofing the bottom of the lake. For this purpose, a joint interpretation was performed using data acquired with different geophysical techniques, such as seismic refraction tomography, electrical resistivity and induced polarization tomography, multichannel analysis of surface waves and horizontal‐to‐vertical spectral ratio of environmental vibration recording. Joint interpretation, supported by cluster analysis techniques, allowed the reconstruction of the geophysical and geotechnical model of the subsoil of the ancient lake, helpful to suggest appropriate techniques for waterproofing the bottom of the lake.

Coastal Groundwater Bodies Modelling Using Geophysical Surveys: The Reconstruction of the Geometry of Alluvial Plains in the North-Eastern Sicily (Italy)

“…To this end, it was beneficial to consider the obtained 3D electrical resistivity models and the results of refraction seismic profiles. However, for a more detailed characterization of the vp and vs. values of lithotypes and the correlation with other observed geophysical parameters, a joint survey Seismic Refraction Tomography (SRT), Electrical Resistivity Tomography (ERT), and Induced Polarization Tomography (IPT) were carried out in coincident position [13]. Furthermore, a Transient Electromagnetic (TEM) survey was performed nearby.…”

“…Furthermore, the net of the actual cost of geophysical instrumentation, the relationship between the amount of data acquired and the economic evaluation of a geophysical survey make geophysical methodologies quite economical when compared to direct investigations. This approach had been often used in many studies regarding stratigraphic [1][2][3] and structural geology [4][5][6][7], the analysis of depositional sequences [8][9][10], archaeological [11][12][13] and civil engineering research [14][15][16]. In these studies, acquired geophysical data constrained by the information derived from direct investigation provide a fundamental tool for the integration and definition of subsurface models.…”

Geophysical Constraints to Reconstructing the Geometry of a Shallow Groundwater Body in Caronia (Sicily)

“…Many authors demonstrated that reliable S-wave-velocity models can be obtained by inverting HVSR data with other stratigraphic and geophysical constraints [47,[49][50][51][52]. In particular, the uncertainty about the HVSR stratigraphic interpretation [53] can be addressed or at least limited using S-wave velocity models obtained by MASW as constraints [46,47,54].…”