soft soil deposits resting on stiffer materials Semblat et al. 2019) and (v) stratigraphic profiles (e.g. 2020) (iv) widespread faulting/fracturing network in rock masses (e.g. paleovalleys and paleotopography Bard and Bouchon 1985 Le Roux et al. 2016) (ii) buried morphological elements (e.g. Site effects can be traced to several subsoil conditions, such as (i) highly heterogeneous subsoil settings (e.g. ![]() Indeed, subsoil heterogeneities induce modifications, in terms of amplitude and frequency, during the propagation of seismic waves through the uppermost geological layers (e.g. The damage distribution in urbanised settings strongly depends on local geology and physical-mechanical properties of both surficial and buried lithotypes. Sitharam and Anbazhagan 2008 SM Working Group 2008 Mihalić et al. The assessment of local seismic response is a key issue for policies finalised to prevention and mitigation of seismic risk (e.g. ![]() Finally, we use these insights to associate the expected distribution of ground motion amplification with the physical stratigraphy of an explosive volcanic setting, with insights for seismic microzonation studies and local seismic response assessment in populated environments. The ground motion amplification is related to both 1D and 2D phenomena including lithological heterogeneity within the upper part of the maar section and interaction of direct S-waves with Rayleigh waves generated at edges of the most superficial lithotypes. The numerical modelling documents a significant ground motion amplification (in the 1–1.5 Hz range) revealed for both seismic scenarios, with a maximum within the centre of the maar. Then, we reconstruct the subsoil model for the Stracciacappa maar in terms of vertical setting and distribution of its mechanical lithotypes, which we investigate for 1D and 2D finite element site response analyses through the application of two different seismic scenarios: a volcanic event and a tectonic event. We first introduce a new multidisciplinary dataset, including geological (fieldwork and log from a 45-m-thick continuous coring borehole), geophysical (electrical resistivity tomographies, single station noise measurements, and 2D passive seismic arrays), and geotechnical (simple shear tests performed on undisturbed samples) approaches. On this regard, we present a multidisciplinary approach in the test area of the Stracciacappa maar (Sabatini Volcanic District, central Italy), with the aim to reconstruct its physical stratigraphy and to discuss how subsoil heterogeneities control the 1D and 2D local seismic response in such a volcanic setting. The quantitative reconstruction of the subsoil model provides a key instrument to understand how the geometry and the internal architecture of outcropping and buried geological units have influence on the propagation of seismic waves. Nowadays, policies addressed to prevention and mitigation of seismic risk need a consolidated methodology finalised to the assessment of local seismic response in explosive volcanic settings.
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