1887
Volume 41, Issue 2
  • ISSN: 0812-3985
  • E-ISSN: 1834-7533

Abstract

The coastal area Marina di Capilungo located ~50 km south-west of Lecce (Italy) is one of the sites at greatest geological risk in the Salento peninsula. In the past few decades, Marina di Capilungo has been affected by a series of subsidence events, which have led in some cases to the partial collapse of buildings and road surfaces. These events had both social repercussions, causing alarm and emergency situations, and economic ones in terms of the funds for restoration.

With the aim of mapping the subsurface karstic features, and so to assess the dimensions of the phenomena in order to prevent and/or limit the ground subsidence events, integrated geophysical surveys were undertaken in an area of ~70 000 m2 at Marina di Capilungo. Large volume voids such as karstic cavities are excellent targets for microgravity surveys. The absent mass of the void creates a quantifiable disturbance in the earth’s gravitational field, with the magnitude of the disturbance directly proportional to the volume of the void. Smaller shallow voids can be detected using ground-penetrating radar (GPR). Microgravimetric and GPR geophysical methods were therefore used. An accurate interpretation was obtained using small station spacing and accurate geophysical data processing. The interpretation was facilitated by combining the modelling of the data with the geological and topographic information for explored caves. The GPR method can complement the microgravimetric technique in determining cavity depths and in verifying the presence of off-line features and numerous areas of small cavities, which may be difficult to be resolved with only microgravimetric data. However, the microgravimetric can complement GPR in delineating with accuracy the shallow cavities in a wide area where GPR measurements are difficult. Furthermore, microgravity surveys in an urban environment require effective and accurate consideration of the effects given by infrastructures, such as buildings, as well as those given by topography, near a gravity station. The acquired negative anomaly in the residual Bouguer anomalies field suggested the presence of possible void features. GPR and modelling data were used to estimate the depth and shape of the anomalous source.

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2010-06-01
2026-01-18

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References

  1. Beres M. Luetscher M. Olivier R. 2001 Integration of ground penetrating radar and microgravimetric methods to map shallow caves: Journal of Applied Geophysics 46 249 262 doi:10.1016/S0926-9851(01)00042-8
    [Google Scholar]
  2. Bergmann T. Robertsson J. O. A. Holliger K. 1998 Finite-difference modeling of electromagnetic wave propagation in dispersive and attenuating media: Geophysics 63 856 867 doi:10.1190/1.1444396
    [Google Scholar]
  3. Bishop I. , Styles P. , Emsley S. J. , and Ferguson N. S. 1997, The detection of cavities using the microgravity technique: case histories from mining and karstic environments, in D. McCann, M. Eddleston, P. J. Femming, G. M. Reeves, eds., Modern geophysics in engineering geology. Special Publications, 12. Geological Society, pp. 155–168.
  4. Blizkovsky M. 1979 Processing and applications in microgravity surveys: Geophysical Prospecting 27 848 861 doi:10.1111/j.1365-2478.1979.tb01002.x
    [Google Scholar]
  5. Bruno E. Calcaterra D. Parise M. 2008 Development and morphometry of sinkholes in coastal plains of Apulia, southern Italy. Preliminary sinkhole susceptibility assessment: Engineering Geology 99 198 209 doi:10.1016/j.enggeo.2007.11.017
    [Google Scholar]
  6. Butler D. K. 1984 Microgravimetric and gravity gradient techniques for detection of subsurface cavities: Geophysics 49 1084 1096 doi:10.1190/1.1441723
    [Google Scholar]
  7. Carcione J. M. 1996 Ground-radar numerical modeling applied to engineering problems: European Journal of. Environmetal Engineering Geophysics 1 65 81
    [Google Scholar]
  8. Cardarelli E. Marrone C. Orlando L. 2003 Evaluation of tunnel stability using integrated geophysical methods: Journal of Applied Geophysics 52 93 102 doi:10.1016/S0926-9851(02)00242-2
    [Google Scholar]
  9. Chamon N. Dobereiner L. 1988 An example of the uses of geophysical methods for the investigation of a cavern in sandstones: Bulletin of the International Association of Engineering Geology 38 37 43 doi:10.1007/BF02590446
    [Google Scholar]
  10. Conyers L. B. , and Goodman D. 1997, Ground-penetrating radar – an introduction for archaeologists: Alta Mira Press.
  11. Daniels J. 1988 Locating caves, tunnels and mines: Geophysics: The Leading Edge of Exploration 7 32 52
    [Google Scholar]
  12. Debeglia N. Dupont F. 2002 Some critical factors for engineering and environmental microgravity investigations: Journal of Applied Geophysics 50 435 454 doi:10.1016/S0926-9851(02)00194-5
    [Google Scholar]
  13. Delle Rose M. Federico A. Parise M. 2004 Sinkhole genesis and evolution in Apulia, and their interrelations with the anthropogenic environment: Natural Hazards and Earth System Sciences 4 747 755
    [Google Scholar]
  14. Geotools Corporation 2000, A division of AOA Geophysics Inc 5828 Balcones Drive, Suite 204 Austin, Texas USA.
  15. Goodman D. 1994 Ground-penetrating radar simulation in engineering and archaeology: Geophysics 59 224 232 doi:10.1190/1.1443584
    [Google Scholar]
  16. Gottsche F. M. 1997, Identification of cavities by extraction of characteristic parameters from ground probing radar reflection data: PhD Thesis, Christian-Albrechts University.
  17. Grandjean G. Leparoux D. 2004 The potential of seismic methods for detecting cavities and buried objects: experimentation at a test site: Journal of Applied Geophysics 56 93 106 doi:10.1016/j.jappgeo.2004.04.004
    [Google Scholar]
  18. Johnson K. S. 1987, Development of the Wink Sink in west Texas due to salt dissolution and collapse: Proceedings 2nd Multidisciplinary Conference on Sinkholes and the Environmental Impact of Karst, Orlando, pp 127–136.
  19. Leucci G. 2003 Evaluation of karstic cave stability using integrated geophysical methods: GeoActa 2 47 60
    [Google Scholar]
  20. Leucci G. 2006 a Integrated geophysical, geological and geomorphological surveys to study the coastal erosion: International Journal of Soil Science 1 146 167 doi:10.3923/ijss.2006.146.167
    [Google Scholar]
  21. Leucci G. 2006 b Contribution of ground-penetrating radar and electrical resistivity tomography to identify the cavity and fractures under the main church in botrugno (Lecce, Italy): Journal of Archaeological Science 33 1194 1204 doi:10.1016/j.jas.2005.12.009
    [Google Scholar]
  22. Leucci G. 2007 a Geophysical investigations to study the physical– mechanical characteristics of the rock in a coastal environment: the cliff of Roca (Lecce, Italy): Journal of Geophysics and Engineering 4 462 475 doi:10.1088/1742-2132/4/4/012
    [Google Scholar]
  23. Leucci G. 2007 b Geoscientific investigations for mapping the subsidence risk in an urban area: Journal of Geophysics and Engineering 4 317 331 doi:10.1088/1742-2132/4/3/S11
    [Google Scholar]
  24. Leucci G. De Giorgi L. 2005 Integrated geophysical surveys to assess the structural conditions of a karstic cave of archaeological importance: Natural Hazards and Earth System Sciences 5 17 22
    [Google Scholar]
  25. Leucci G. De Giorgi L. 2006 Experimental studies on the effects of fracture on the p and s wave velocity propagation in sedimentary rock (‘calcarenite del salento’): Engineering Geology 84 130 142 doi:10.1016/j.enggeo.2005.12.004
    [Google Scholar]
  26. Leucci G. Negri S. Carrozzo M. T. Nuzzo L. 2002 Use of ground penetrating radar to map subsurface moisture variations in an urban area: Journal of Environmental & Engineering Geophysics 7 69 77 doi:10.4133/JEEG7.2.69
    [Google Scholar]
  27. Meier E. , Huggenberger P. , Stiefelhagen W. , Muller I. , and Christe R. 1997, Geophysical methods as a tool for speleological and geotechnical investigation in karst Maira, Plateau de Bure JU, Switzerland: Proceedings of the 12th International Congress of Speleology, Switzerland, 2, 221–224.
  28. Melchior P. 1983, The tides of the planet earth: Pergamon.
  29. Osborne R. A. L. 2002 Cave breakdown by vadose weathering: International Journal of Speleology 31 37 53
    [Google Scholar]
  30. Patterson D. A. Davey J. C. Cooper A. H. Ferris J. K. 1995 The investigation of dissolution subsidence incorporating microgravity geophysics at Ripon, Yorkshire: Quarterly Journal of Engineering Geology 28 83 94 doi:10.1144/GSL.QJEGH.1995.028.P1.08
    [Google Scholar]
  31. Radhakrishna Murthy I. V. Swamy K. V. 1996 Gravity anomalies of a vertical cylinder of polygonal cross-section and their inversion: Computers & Geosciences 22 625 630 doi:10.1016/0098-3004(95)00126-3
    [Google Scholar]
  32. Rousset D. , Genthon P. , Perroud H. , and Senechal G. 1998, Detection and characterization of near surface small karstic cavities using integrated geophysical surveys: Proceedings of the 4th Meeting of Environmental and Engineering Geophysical Society, European Section, Barcelona, Spain. pp. 367–370.
  33. Sandmeier K. J. 2008, Reflex 5.0 Manual Sandmeier Software Zipser Strabe 1, D-76227 (Karlsruhe, Germany).
  34. Styles P. 2004, Detection of caves by microgravity geophysics, in A. C. Waltham, F. G. Bell and M. G. Culshaw eds., Bahamas sinkholes and subsidence: Springer.
  35. Styles P. McGrath R. Thomas E. Cassidy N. J. 2005 The use of microgravimetry for cavity characterization in karstic terrains: Quarterly Journal of Engineering Geology and Hydrogeology 38 155 169 doi:10.1144/1470-9236/04-035
    [Google Scholar]
  36. Styles P. , Toon S. , Thomas E. , and Skittral M. 2006, Microgravity as a tool for the detection, characterization and prediction of geohazard posed by abandoned mining cavities: First Break, vol 24.
  37. Telford W. M. , Gedart L. P. , and Sheriff R. E. 1990, Applied geophysics, 2nd edn: Cambridge University Press.
  38. Tharp T. M. 1999 Mechanics of upward propagation of cover-collapse sinkholes: Engineering Geology 52 23 33 doi:10.1016/S0013-7952(98)00051-9
    [Google Scholar]
  39. Van schoor M. 2002 Detection of sinkholes using 2D electrical resistivity imaging: Journal of Applied Geophysics 50 393 399 doi:10.1016/S0926-9851(02)00166-0
    [Google Scholar]
  40. Yilmaz O. 1987 Seismic data processing: Society of Exploration Geophysicists.
  41. Yule D. E. Sharp M. K. Butler D. K. 1998 Microgravity investigations of foundation conditions: Geophysics 63 95 103 doi:10.1190/1.1444331
    [Google Scholar]
/content/journals/10.1071/EG09029
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Microgravimetric and ground penetrating radar geophysical methods to map the shallow karstic cavities network in a coastal area (Marina Di Capilungo, Lecce, Italy)
Exploration Geophysics 41, 178 (2010); https://doi.org/10.1071/EG09029
/content/journals/10.1071/EG09029
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  • Article Type: Research Article
Keyword(s): ground-penetrating radar, Karstic features map, microgravimetric.

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