Data analysis of active geological processes by development of geomatic models - Analisi e sviluppo di modelli geomatici per l’acquisizione di dati provenienti da differenti sistemi geologici attivi

This research describes the surface expressions (deformation) of active geological processes linked to certain space-time relationships, localised in central Sicily, through geodetic, geophysical and geological analyses. The surface expressions of active geological processes have been distinguished into two types, those linked to long-term deformation stages of tectonic origin (regional scale) and the transient ones (local scale) linked to deformation processes resulting from the main tectonic dynamics. This research also provides guidelines for monitoring and surveying phenomena consequent to active tectonic processes, formulated according to geological, kinematic and seismological models. These guidelines have been synthesised considering the special characteristics of the individual methodologies and instruments used during this project. The first part of the thesis introduces the concepts of active geological processes, their monitoring and relief, the study areas (open-air laboratories) being studied by the GEODynamics & GEOMatic Laboratory research group, and the one being studied located in central Sicily (Central Sicily Laboratory). Based on the conceptual model of the Central Sicily Laboratory, the geological, kinematic and seismological models and possible scenarios were defined. Subsequently, the applied methodologies, the principles on which they are based and their application were introduced. The main objective of the research is to detect and define the surface kinematic behaviour that characterises the study area and consequently define the parameters useful for the development of statistical, analytical and numerical models. SAR interferometric data were processed, according to the A-DInSAR techniques of Permanent Scatters (PS) by means of StaMPS-MTI to obtain the field deformation of the Laboratory of Central Sicily. GNSS campaigns were also carried out on some sites of the IGM95 network integrated with data from the permanent networks on the Sicilian territory (RING, RDN and TopgeoLive). The integration between PS and GNSS data makes it possible to define the real velocity field and to validate the velocity field obtained through PS. In addition, a geodetic topographic (3D) detail analysis was carried out by APR (remotely piloted aircraft) photogrammetry in the area affected by sedimentary volcanism (Maccalube di Santa Barbara, Caltanissetta) to monitor and detect deformations related to mud volcano activity. The results obtained made it possible to draw up a seismotectonic map of the Laboratory of Central Sicily supported by horizontal and vertical kinematic data and to define guidelines for monitoring geological processes in areas affected by active tectonics. Finally, areas have been identified in which the acting dynamics need to be investigated with further studies, such as areas affected by interseismic disequilibrium (Hyblean Plateau), areas in which phenomena of decoupling of regional deep and local surface deformation processes are detected (western slopes of Etna), and areas that bear witness to uplift of tectonic origin (south-western area of western Sicily.