Hazard mitigation from rockfalls and landslides is a priority in densely populated areas. A proper characterization of the inner structure of the rock mass is key to the comprehension of the mechanisms enhancing the slope instabilities. To this aim multi-scale geophysical methods can provide a novel and valuable tool for an high-resolution imaging of the internal structure of the rock mass and unique constraints on the physical state of the medium. We present here a cross-hole seismic tomography survey coupled with laboratory ultrasonic velocity measurements and physical properties determination on rock samples to characterize the damaged and potentially unstable granitic cliff of Madonna del Sasso (NW Italy). Results allowed to achieve two main advances, in terms of obtaining: i) a lithological interpretation of the velocity field obtained at the site, ii) a systematic correlation of the measured velocities with physical properties (density and porosity) and macroscopic features of the granite (weathering and anisotropy) of the cliff. Geophysical tests revealed to be crucial for the imaging at depth of the main fractures affecting the cliff and for the understanding of the variations in the seismic velocity between altered and intact rock to be used in further microseismic monitoring studies.

Multiscale geophysical characterization of an unstable rock mass

COLOMBERO, CHIARA;COMINA, Cesare;UMILI, GESSICA;VINCIGUERRA, Sergio Carmelo
2016

Abstract

Hazard mitigation from rockfalls and landslides is a priority in densely populated areas. A proper characterization of the inner structure of the rock mass is key to the comprehension of the mechanisms enhancing the slope instabilities. To this aim multi-scale geophysical methods can provide a novel and valuable tool for an high-resolution imaging of the internal structure of the rock mass and unique constraints on the physical state of the medium. We present here a cross-hole seismic tomography survey coupled with laboratory ultrasonic velocity measurements and physical properties determination on rock samples to characterize the damaged and potentially unstable granitic cliff of Madonna del Sasso (NW Italy). Results allowed to achieve two main advances, in terms of obtaining: i) a lithological interpretation of the velocity field obtained at the site, ii) a systematic correlation of the measured velocities with physical properties (density and porosity) and macroscopic features of the granite (weathering and anisotropy) of the cliff. Geophysical tests revealed to be crucial for the imaging at depth of the main fractures affecting the cliff and for the understanding of the variations in the seismic velocity between altered and intact rock to be used in further microseismic monitoring studies.
675
275
289
http://www.sciencedirect.com/science/article/pii/S0040195116001529
unstable rock mass, cross-hole seismic tomography, ultrasonic pulse velocity, physical and mechanical properties, granite
Colombero, Chiara; Comina, Cesare; Umili, Gessica; Vinciguerra, Sergio
File in questo prodotto:
File Dimensione Formato  
versione_autore_4aperto.pdf

Accesso aperto con embargo fino al 22/04/2018

Descrizione: Articolo principale
Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 2.79 MB
Formato Adobe PDF
2.79 MB Adobe PDF Visualizza/Apri
Tectonophys_2016_Comina.pdf

Accesso riservato

Tipo di file: PDF EDITORIALE
Dimensione 3.01 MB
Formato Adobe PDF
3.01 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2318/1616367
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 11
  • ???jsp.display-item.citation.isi??? 11
social impact