Toward a joint catalogue of recent seismicity in western Greece: preliminary results


Published: Jan 1, 2007
Keywords:
relocation hypoinverse Ionian
Z. Roumelioti
A. Ganas
E. Sokos
P. Petrou
A. Serpetsidaki
G. Drakatos
Abstract

Routine catalogue phase data of three Greek permanent seismic networks are merged and jointly used to relocate earthquakes in western Greece. Processed data refer to the time period from 2000 to 2005 and to the geographical area between 35- 42°N and 19-22Έ. After the merging procedure, the number of events in the joint catalogue is increased by more than 3000 compared to the individual pre-existing catalogues. Earthquakes are relocated using the Hypoinverse algorithm and several different combinations of ID velocity models and phase weighting schemes. Among these two tested factors, S-phase weights are found to affect the relocation results more drastically. In fact, minimum mean rms, erh and erz values (0.28 sees, 3.6 km and 5.8 km, respectively) are found when S-phases are neglected. Relocated epicenters appear more clustered and illuminate well-known, as well as obscure, seismotectonic structures of the area

Article Details
  • Section
  • Geophysics and Seismology
Downloads
Download data is not yet available.
References
Karakostas, V.G., Papadimitriou, E.E., and Papazachos, C.B., 2004. Properties of the 2003 Lefkada,
Ionian Islands, Greece, earthquake seismic sequence and seismicity triggering, Bull. Seism. Soc. Am., 94( 5), 1976-1981.
Kiratzi, Α., and Louvari, E., 2003. Focal mechanisms of shallow earthquakes in the Aegean Sea and the surrounding lands determined by waveform modeling: a new database, Journal of Geodynamics, 36, 251 - 274.
Klein, F.W., 2002. User's Guide to HYPOINVERSE-2000, a Fortran program to solve for earthquake locations and magnitudes, Open File Report 02-171, U.S. Geological Survey.
Lee, W.H.K., and Lahr, J.C., 1972. HYP071: A computer program for determining hypocenter, magnitude, and first motion pattern of local earthquakes, U.S. Geological Survey Open-File Report.
Louvari, E., Kiratzi, A.A., and Papazachos, B.C., 1999. The Cephalonia transform fault and its extension to western Lefkada island (Greece), Tectonophysics, 308, 223-236.
Papazachos, B.C., Papadimitriou, E.E., Kiratzi, A.A., Papazachos, C.B., and Louvari E.K., 1998. Fault plane solutions in the Aegean Sea and the surrounding area and their tectonic implication, Bolletino di Geofìsica Teorica ed Applicata, 39, 199-218.
Roumelioti, Z., Benetatos, Ch, Kiratzi, Α., Stavrakakis, G., and Melis, N., 2004. Evidence for sinistral strike-slip faulting in western Péloponnèse (Greece): A study of the 2 December 2002 (M5.5) Vartholomio earthquake sequence, Tectonophysics, 387, 65 - 79.
Skarlatoudis, Α., 2002. Relocation of hypocentral earthquake parameters in Greece with the use of data from local experiments and effects in the strong motion attenuation relations, MSc Thesis, Aristotle University of Thessaloniki, 120pp.
Wessel, P., and Smith, W.H.F., 1998. New improved version of the Generic Mapping Tools released, EOS Trans. AGU 79, 579.
Zahradnik, J., Serpetsidaki, A. Sokos, E., and Tselentis, G.-A., 2005. Iterative deconvolution of regional waveforms and a double-event interpretation of the 2003 Lefkada earthquake, Greece, Bull. Seism. Soc. Am., 95, No. 1, 159 - 172, doi:10.1785/0120040035.
Most read articles by the same author(s)