EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Evaluation of stratigraphic effects on seismic site response over large areas: the case study of Italy

Gaetano Falcone1, Gianluca Acunzo1, Amerigo Mendicelli1, Federico Mori1, Giuseppe Naso2, Edoardo Peronace1, Attilio Porchia1, Gino Romagnoli1, Emanuele Tarquini1, and Massimiliano Moscatelli1
Gaetano Falcone et al.
  • 1Consiglio Nazionale delle Ricerche, Istituto di Geologia Ambientale e Geoingegneria, Roma, Italy (
  • 2Dipartimento della Protezione Civile (DPC), via Vitorchiano 2, 00189 Roma, Italy

Estimation of site effects over large areas is a key-issue for land management and emergency system planning in a risk mitigation perspective. In general, site-conditions are retrieved from available global datasets and the ground-shaking estimation is based on ground motion prediction equations.

An advanced procedure to estimate site effects over large areas is here proposed with reference to the Italian territory. Site-condition were defined for homogenous morpho-geological areas in accordance to the borehole logs and the geophysical data archived in the Italian database for seismic microzonation ( Ground motion modifications were determined by means of about 30 milion of one-dimensional numerical simulations of local seismic site response. Correlations between amplification factors (i.e. the ratio between free-field and outcrop response spectra), AF, and site-condition (i.e. harmonic mean of the shear wave velocity in the upper 30 m of the deposit, VS30) were determined for each morpho-geological homogeneous area depending on the reference seismic intensity (i.e. referred to the outcropping stiff rock characterised by VS30 ≥ 800 m/s). The AF-VS30 correlations were proved to satisfactory forecast the site effects when compared with the results of site specific estimation of local seismic site response.

How to cite: Falcone, G., Acunzo, G., Mendicelli, A., Mori, F., Naso, G., Peronace, E., Porchia, A., Romagnoli, G., Tarquini, E., and Moscatelli, M.: Evaluation of stratigraphic effects on seismic site response over large areas: the case study of Italy, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-2014,, 2021.