Assessing subsoil void hazards along a road system using H/V measurements, ERTs and IPTs to support local decision makers

Between 2008 and 2014, nine sinkholes occurred in northeastern Elba Island (Tuscany, Italy), an area with mostly flat terrain (called “Il Piano”) separating the municipalities of Rio nell’Elba and Rio Marina. The last sinkhole damaged the only road (SP26) between the harbour of Rio Marina and the northwestern part of the island. A bypass was immediately built, but the SP26 remains closed. Considering that sinkholes could be densely clustered in sinkhole prone areas, their detection and forecasting are key aspects of local administrative policies. In this paper, we present the results of an integrated geophysical survey aimed at (i) characterizing the geology of the area surrounding the SP26, and (ii) assessing the subsoil void hazard around the road system to support the decision to replace or restore the SP26. Therefore, for the purposes of this research, 120 single-station seismic noise measurements were taken following the horizontal-to-vertical spectral ratio (H/V) or Nakamura technique, while eight 2D electrical resistivity tomography (ERT) and 17 3D-ERT/induced polarisation measurements were also carried out in the study area. The H/V method allowed the estimation of the mean thickness of the alluvium, whereas the 2D/3D-ERTs and IPTs permitted the characterisation of the electrical behaviours of the materials and the localisation of the lenticular sand and gravel bodies within a sandy silt layer. The large amount of collected data made the zonation of the subsoil void hazards possible.

[1]  T. Dobecki,et al.  Geophysical applications to detect sinkholes and ground subsidence , 2006 .

[2]  P. Styles,et al.  The detection of cavities using the microgravity technique: case histories from mining and karstic environments , 1997, Geological Society, London, Engineering Geology Special Publications.

[3]  G. Ciotoli,et al.  A review of natural sinkhole phenomena in Italian plain areas , 2008 .

[4]  R. Barker,et al.  Practical techniques for 3D resistivity surveys and data inversion1 , 1996 .

[5]  Donat Fäh,et al.  A theoretical investigation of average H/V ratios , 2001 .

[6]  R. Fanti,et al.  H/V measurements as an effective tool for the reliable detection of landslide slip surfaces: Case studies of Castagnola (La Spezia, Italy) and Roccalbegna (Grosseto, Italy) , 2017 .

[7]  Julian Ivanov,et al.  Evaluating hazards at salt cavern sites using multichannel analysis of surface waves , 2013 .

[8]  Gaetano Ranieri,et al.  Three-dimensional Electrical Resistivity Tomography to control the injection of expanding resins for the treatment and stabilization of foundation soils , 2011 .

[9]  Stratos Zacharopoulos,et al.  Guidelines for the implementation of the H/V spectral ratio technique on ambient vibrations measurements, processing and interpretation , 2004 .

[10]  E. Rizzo,et al.  Sinkhole risk assessment by ERT: The case study of Sirino Lake (Basilicata, Italy) , 2016 .

[11]  T. Dahlin,et al.  A numerical comparison of 2D resistivity imaging with 10 electrode arrays , 2004 .

[12]  M. Lazzari,et al.  Near surface geophysics techniques and geomorphological approach to reconstruct the hazard cave map in historical and urban areas , 2010 .

[13]  Dwain K. Butler,et al.  Microgravimetric and gravity gradient techniques for detection of subsurface cavities , 1984 .

[14]  Ettore Cardarelli,et al.  2D data modelling by electrical resistivity tomography for complex subsurface geology , 2006 .

[15]  E. Intrieri,et al.  Definition of sinkhole triggers and susceptibility based on hydrogeomorphological analyses , 2017, Environmental Earth Sciences.

[16]  T. Dobecki.  Sinkholes and pitfalls in urban geophysics , 2010 .

[17]  Richard D. Miller.  Introduction to this special section: Urban geophysics , 2013 .

[18]  Nicola Casagli,et al.  Testing cost-effective methodologies for flood and seismic vulnerability assessment in communities of developing countries (Dajç, northern Albania) , 2016 .

[19]  Marijan Herak,et al.  Increasing Seismic Safety by Combining Engineering Technologies and Seismological Data , 2009 .

[20]  A. Bitri,et al.  Integrated geophysical approach in assessing karst presence and sinkhole susceptibility along flood-protection dykes of the Loire River, Orléans, France , 2014 .

[21]  Chunho Chang,et al.  Early sinkhole detection using a drone-based thermal camera and image processing , 2016 .

[22]  Wanfang Zhou,et al.  Effective electrode array in mapping karst hazards in electrical resistivity tomography , 2002 .

[23]  Nicola Casagli,et al.  Monitoring of the vibration induced on the Arno masonry embankment wall by the conservation works after the May 25, 2016 riverbank landslide , 2017, Geoenvironmental Disasters.

[24]  Michael Ezersky,et al.  Geoelectric structure of the Ein Gedi sinkhole occurrence site at the Dead Sea shore in Israel , 2008 .

[25]  Nicola Casagli,et al.  Assessing the safety of schools affected by geo-hydrologic hazards: The geohazard safety classification (GSC) , 2016 .

[26]  A. Eriksen,et al.  Field Geophysics: Milsom/Field Geophysics , 2011 .

[27]  Marijan Herak.  The Use of Ambient Noise for Building and Soil Characterisation , 2009 .

[28]  D. Butler.  Microgravimetric And Gravity-Gradient Techniques For Detection of Subsurface Cavities , 1983 .

[29]  E. Vázquez-Suñé,et al.  High-resolution seismic characterization in an urban area: Subway tunnel construction in Barcelona, Spain , 2008 .

[30]  F. Mulargia,et al.  VS30 Estimates Using Constrained H/V Measurements , 2009 .

[31]  F. Martínez-Moreno,et al.  Combined microgravity, electrical resistivity tomography and induced polarization to detect deeply buried caves: Algaidilla cave (Southern Spain) , 2013 .

[32]  P. J. Fenning,et al.  Urban Geophysics — Seeking the Difficult and Hidden , 1994 .

[33]  John M. Reynolds,et al.  An Introduction to Applied and Environmental Geophysics , 1997 .

[34]  Giuseppe Lombardo,et al.  Evaluation of seismic site response nearby underground cavities using earthquake and ambient noise recordings: A case study in Catania area, Italy , 2011 .

[35]  G. Ruggieri,et al.  Sericitic alteration at the La Crocetta deposit (Elba Island, Italy): interplay between magmatism, tectonics and hydrothermal activity , 2003 .

[36]  Deodato Tapete,et al.  An electric and electromagnetic geophysical approach for subsurface investigation of anthropogenic mounds in an urban environment , 2016 .

[37]  Jeffrey G. Paine,et al.  Assessing Collapse Risk in Evaporite Sinkhole-prone Areas Using Microgravimetry and Radar Interferometry , 2012 .

[38]  R. Henderson.  Urban Geophysics — A Review , 1992 .

[39]  Christian Camerlynck,et al.  Simultaneous use of electrostatic quadrupole and GPR in urban context: Investigation of the basement of the Cathedral of Girona (Catalunya, Spain) , 2000 .

[40]  Ulrich Polom,et al.  Sinkholes in the city of Hamburg—New urban shear-wave reflection seismic system enables high-resolution imaging of subrosion structures , 2012 .

[41]  M. I. Seht,et al.  Microtremor measurements used to map thickness of soft sediments , 1999 .

[42]  Piernicola Lollino,et al.  A preliminary analysis of failure mechanisms in karst and man-made underground caves in Southern Italy , 2011 .

[43]  Emad Akawwi,et al.  Seismic Surface-wave Prospecting Methods for Sinkhole Hazard Assessment along the Dead Sea Shoreline , 2013 .

[44]  L. Baillet,et al.  Environmental seismology: What can we learn on earth surface processes with ambient noise? , 2015 .

[45]  N. Casagli,et al.  Sinkhole monitoring and early warning: An experimental and successful GB-InSAR application , 2015 .

[46]  Gaetano Ranieri,et al.  4D cross-borehole electrical resistivity tomography to control resin injection for ground stabilization: a case history in Venice (Italy) , 2013 .

[47]  M. Soriano,et al.  Mapping subsurface karst features with GPR: results and limitations , 2009 .

[48]  A. P. Juan,et al.  Actual extension of sinkholes: Considerations about geophysical, geomorphological, and field inspection techniques in urban planning projects in the Ebro basin (NE Spain) , 2013 .

[49]  P. Dell’Aversana.  Integration loop of of ‘global offset’ seismic, continuous profiling magnetotelluric and gravity data , 2003 .

[50]  V. Bortolotti,et al.  GEOLOGY OF CENTRAL AND EASTERN ELBA ISLAND, ITALY , 2001 .

[51]  F. Mulargia,et al.  The Effect of Velocity Inversions on H/V , 2009 .

[52]  M. Parise,et al.  Geomorphology and natural hazards in karst areas: A review , 2011 .

[53]  Eric A. White,et al.  Estimation of Bedrock Depth Using the Horizontal-to-vertical (H/V) Ambient-noise Seismic Method , 2008 .

[54]  Francisco J. Chávez-García,et al.  Are microtremors useful in site response evaluation , 1994 .

[55]  S. Castellaro.  The complementarity of H/V and dispersion curves , 2016 .

[56]  F. Innocenti,et al.  Two-stage growth of laccoliths at Elba Island, Italy , 2002 .

[57]  S. Szalai,et al.  Classification of surface geoelectric arrays , 2007 .

[58]  Douglas L. Smith.  Application of the pole-dipole resistivity technique to the detection of solution cavities beneath highways , 1986 .

[59]  Y Nakamura,et al.  A METHOD FOR DYNAMIC CHARACTERISTICS ESTIMATION OF SUBSURFACE USING MICROTREMOR ON THE GROUND SURFACE , 1989 .

[60]  R. Davies,et al.  Integrated geophysical surveys applied to karstic studies , 2003 .

[61]  J. Wasowski,et al.  Detection of directivity in seismic site response from microtremor spectral analysis , 2008 .

[62]  Detection of caves by gravimetry , 1964 .

[63]  A. Revil,et al.  Self-potential signals associated with preferential groundwater flow pathways in sinkholes , 2006 .

[64]  E. Cardarelli,et al.  Detection and imaging of piping sinkholes by integrated geophysical methods , 2014 .

[65]  E. Cardarelli,et al.  Electrical Resistivity and Seismic Refraction Tomography to Detect Buried Cavities , 2008 .

[66]  V. Tofani,et al.  Spatial modeling of pyroclastic cover deposit thickness (depth to bedrock) in peri‐volcanic areas of Campania (southern Italy) , 2018 .

[67]  J. Wasowski,et al.  What we can learn about slope response to earthquakes from ambient noise analysis: An overview , 2014 .

[68]  Georg Kaufmann,et al.  Geophysical mapping of solution and collapse sinkholes , 2014 .

[69]  V. Pazzi,et al.  Could Ambient Vibrations Be Related to Cerithidea decollate Migration , 2017 .

[70]  R. Parker,et al.  Occam's inversion; a practical algorithm for generating smooth models from electromagnetic sounding data , 1987 .