A STUDY OF MICROTREMOR HVSR IN THE RIO-ANTIRIO AREA, (GREECE)


Published: Jul 27, 2016
Keywords:
Nakamura method Horizontal to Vertical Spectral Ratio vs Azimuth fundamental frequency
M.E. Norda
A. Prapiga
P. Paraskevopoulos
G.A Tselentis
Abstract

Horizontal to Vertical Spectral Ratio (HVSR) method has been applied on ambient noise records at the Rio- Antirio area (central Greece). The dataset used was recorded during 7 days by 12 temporary seismic stations deployed in the area. The stations were laid out along a profile and their interval was approximately 500m. The main part of the processing was done using Geopsy software. The aim of this study was to estimate the fundamental frequency at the station sites and its variation with time and azimuth. The processing results showed that for most stations along the profile, the peaks of the HVSR curve are not strong enough and often there are, more than one, peaks, which seem to be persistent during the whole recording time. When taking the azimuth into account, some of the stations show dominant and persistent directions were the HVSR ratio is stronger, while it has been observed that this direction could vary for different frequency peaks of the same stations. Finally, the top sediment layer’s geometry and thickness were estimated using Vs velocity results from nearby crosshole measurements.

Article Details
  • Section
  • Geophysics and Seismology
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References
Avallone, A., Briole, P., Agatza-Balodimou, A.M., Billiris, H., Charade, O., Mitsakaki, C.,
Nercessian, A., Papazissi, K., Paradissis, D. and Veis, G., 2004. Analysis of eleven years of
deformation measured by GPS in the Corinth Rift Laboratory area, C. R. Geosci., 336(4-5),
-311.
C.P.W.L, 1992. Rion Antirrion junction bridge additional geotechnical investigations carried out by
the geotechnical engineering section of the central public works laboratory (C.P.W.L),
C.P.W.L report.
Konno, K. and Ohmachi, T., 1998. Ground-motion Characteristics Estimated from Spectral Ratio
between Horizontal and Vertical Components of Microtremor, Bull. Seismol. Soc. Am, 88,
-241.
Nakamura, Y., 1989. A method for Dynamic Characteristics Estimation of Subsurface using
Microtremor on the Ground Surface, Quarterly Report of Railway Technical Research
Institute (RTRI), 30, 1.
Nakamura, Y., 1997. Seismic Vulnerability Indices for Ground and Structures Using Microtremor,
World Congress on Railway Research in Florence, Italy, November 1997.
Oliveto, A., Mucciarelli, M. and Caputo, R. 2004. HVSR prospecting in multi-layered
environments: An example from the Tyrnavos Basin (Greece), J. Seism., 8, 395-406.
Paraskevopoulos, P., 2015. HVSRmat v 0.5 User’s manual, 10 pp.
SESAME, 2004. Guidelines for the implementation of the H/V spectral ratio technique on ambient
vibrations: measurements, processing and interpretation, SESAME report Deliverable-D23,
pp.
Tselentis, G.-A., Serpetsidaki, A., Martakis, N., Sokos, E., Paraskevopoulos, P. and Kapotas, S.,
Local high resolution passive seismic tomography and Kohonen neural networks,
application at the Rio-Antirrio Strait, Central Greece, Geophysics, 72(4), B93-B106.