Journal of Seismology

, Volume 20, Issue 1, pp 319–332 | Cite as

Local magnitude calibration of the Hellenic Unified Seismic Network

  • E. M. Scordilis
  • D. Kementzetzidou
  • B. C. Papazachos
Original Article


A new relation is proposed for accurate determination of local magnitudes in Greece. This relation is based on a large number of synthetic Wood-Anderson (SWA) seismograms corresponding to 782 regional shallow earthquakes which occurred during the period 2007–2013 and recorded by 98 digital broad-band stations. These stations are installed and operated by the following: (a) the National Observatory of Athens (HL), (b) the Department of Geophysics of the Aristotle University of Thessaloniki (HT), (c) the Seismological Laboratory of the University of Athens (HA), and (d) the Seismological Laboratory of the Patras University (HP). The seismological networks of the above institutions constitute the recently (2004) established Hellenic Unified Seismic Network (HUSN). These records are used to calculate a refined geometrical spreading factor and an anelastic attenuation coefficient, representative for Greece and surrounding areas, proper for accurate calculation of local magnitudes in this region. Individual station corrections depending on the crustal structure variations in their vicinity and possible inconsistencies in instruments responses are also considered in order to further ameliorate magnitude estimation accuracy. Comparison of such calculated local magnitudes with corresponding original moment magnitudes, based on an independent dataset, revealed that these magnitude scales are equivalent for a wide range of values.


Local magnitude Synthetic Wood-Anderson Geometrical spreading Anelastic attenuation 



We appreciate the thorough review of the anonymous reviewer which has greatly improved the article. A special “thank you” goes to Prof. G. Tsaklidis (Department of Statistics and Operational Research of our University) for his assistance with the MINUIT software. The maps were produced with the GMT software (Wessel and Smith 1995). This research has been co‐financed by the European Union (European Social Fund—ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF)–Research Funding Program: THALES. Investing in knowledge society through the European Social Fund. Project SEISMO FEAR HELLARC.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.Department of Geophysics, School of Geology, Faculty of ScienceAristotle University of ThessalonikiThessalonikiGreece

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