SISMOMED project: Study of the seismicity of the central Mediterranean for the definition of seismogenic structures and crustal-lithospheric models

The Central Mediterranean is a geodynamically very complex area and is the result of the interaction between the European and African plates. Despite numerous studies, current models that attempt to describe the detailed kinematics and dynamics of this interaction have insufficient resolution or do not cover the entire Central Mediterranean area.The major challenge is to build high-resolution crustal-lithospheric models for understanding past and future geodynamic evolution of the region and for accurate assessment of seismic and tsunami hazards associated with tectonic structures. The main problems lie in poor and heterogeneous data coverage and the predominantly mono-disciplinary approach used in the literature.This PhD thesis aims to improve current knowledge of the shallow and deep structures of the central Mediterranean and to contribute to knowledge of the complex geodynamics of the region.The use of data from different disciplines has enabled the coverage areas that otherwise would have shown significant gaps.Seismic reflection profiles, P-wave velocity models (Vp), S-wave velocity models (Vs) converted to Vp through appropriate Vp/Vs ratios, and density models, have enabled the construction of the most extensive and high-resolution map of the Central Mediterranean Moho currently available. This shows strong lateral variation and good correlation with tectonic structures in the region. Using the same data and with the inclusion of well data, a preliminary crustal 3D model was produced. Despite some holes, this model is consistent with the tectonic and morphobathymetric structures of the study area. In addition, it is an important tool to build velocity models useful for optimizing the location of the hypocenter of earthquakes.Statistical analysis of seismic earthquakes, through the use of purpose-written scripts, allowed the identification and construction of two lithospheric seismogenetic volumes (LSVs) located in the west-central sector of the Sicily Channel and a first subduction ionic crustal seismogenetic volume (CSV). The LSVs were related to the tectonic structures, banks and volcanoes located in the area and compared with existing rheological models. The geometric features of the upper and lower surfaces constituting the CSV were analyzed, and the slab was compared with those proposed in the literature.This thesis project is a valuable tool to advance understanding of the geodynamic framework of the central Mediterranean, as well as to delineate surface and subsurface structures and associated seismic and tsunami hazards.