For landslide risk mitigation and sustainable planning in urban areas affected by landslides, multi-hazards approaches are recommended. Multi-hazards schemes are complicated because of the occurrence of independent events which can be linked in chains or absolute. Non-invasive, passive and high-resolution geophysical techniques, represent a feasible strategy for detecting and monitoring ground effects, as well as a tool for calibrating numerical models devoted to reproducing multi-hazard scenarios in a predictive perspective. This research is part of a PhD project focused on the application of monitoring and prediction approaches for interpretating ground instability effects in the multi-hazard framework. To this aim, the urban area of San Vito Romano (SVR) town has been selected due to the presence of a historical landslide consisting in a dynamic active earth slide with a clear retrogressive behavior. The landslide, is frequently triggered by intense rainfalls and it could be also reactivated by earthquakes; this activity is also prepared and continuously stressed by changes in soil moisture and freezing and thawing cycles. The adopted method can be performed by employing single- and double-stations arrangements including four three-componenet SARA velocimeters (VelBox, model SL06 2 Hz sensor) which can provide continuous seismic noise recordings suitable for local ambient resonance analysis and modelling. The same array can be also used for seismic interferometry to compare with the deformation zoning inferred from InSAR interferometry. In a double-station configuration, the relative change in velocity (dV/V) is obtained between station pairs, where the ambient noise wavefield recorded at two stations after pre-processing, is cross-correlated in the frequency domain. The change in velocity is obtained by comparing the reference cross-correlogram (stacked over the entire length of record) with the current cross-correlogram over a selected length of time window in the framework of ambient noise interferometry. Furthermore, within this project framework, the potential of single-station ambient seismic noise analyses, such as HVSR (change in natural period (dT/T)) and change in peak-polarization (dP/P), will be explored for the time-lapse monitoring of the SVR landslide. The dV/V, dT/T, and dP/P can be used as a proxy for detecting the landslide mechanisms. The reliability of multi-parametric results (dV/V, dT/T, and dP/P) will be investigated by statistical comparison approaches such as change-point detection.
Application of time-lapse ambient seismic noise for multi-hazard assessment: the San Vito Romano (Roma, Italy) case study / Marano, S.; Hussain, Y.; Grechi, G.; Rivellino, S.; Martino, S.. - (2024). (Intervento presentato al convegno 8th AIGA congress tenutosi a Napoli).
Application of time-lapse ambient seismic noise for multi-hazard assessment: the San Vito Romano (Roma, Italy) case study
Marano S.;Hussain Y.;Grechi G.;Rivellino S.;Martino S.
2024
Abstract
For landslide risk mitigation and sustainable planning in urban areas affected by landslides, multi-hazards approaches are recommended. Multi-hazards schemes are complicated because of the occurrence of independent events which can be linked in chains or absolute. Non-invasive, passive and high-resolution geophysical techniques, represent a feasible strategy for detecting and monitoring ground effects, as well as a tool for calibrating numerical models devoted to reproducing multi-hazard scenarios in a predictive perspective. This research is part of a PhD project focused on the application of monitoring and prediction approaches for interpretating ground instability effects in the multi-hazard framework. To this aim, the urban area of San Vito Romano (SVR) town has been selected due to the presence of a historical landslide consisting in a dynamic active earth slide with a clear retrogressive behavior. The landslide, is frequently triggered by intense rainfalls and it could be also reactivated by earthquakes; this activity is also prepared and continuously stressed by changes in soil moisture and freezing and thawing cycles. The adopted method can be performed by employing single- and double-stations arrangements including four three-componenet SARA velocimeters (VelBox, model SL06 2 Hz sensor) which can provide continuous seismic noise recordings suitable for local ambient resonance analysis and modelling. The same array can be also used for seismic interferometry to compare with the deformation zoning inferred from InSAR interferometry. In a double-station configuration, the relative change in velocity (dV/V) is obtained between station pairs, where the ambient noise wavefield recorded at two stations after pre-processing, is cross-correlated in the frequency domain. The change in velocity is obtained by comparing the reference cross-correlogram (stacked over the entire length of record) with the current cross-correlogram over a selected length of time window in the framework of ambient noise interferometry. Furthermore, within this project framework, the potential of single-station ambient seismic noise analyses, such as HVSR (change in natural period (dT/T)) and change in peak-polarization (dP/P), will be explored for the time-lapse monitoring of the SVR landslide. The dV/V, dT/T, and dP/P can be used as a proxy for detecting the landslide mechanisms. The reliability of multi-parametric results (dV/V, dT/T, and dP/P) will be investigated by statistical comparison approaches such as change-point detection.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.