NHESS Natural Hazards and Earth System Sciences NHESS Nat. Hazards Earth Syst. Sci. 1684-9981 Copernicus Publications Göttingen, Germany 10.5194/nhess-9-905-2009 Investigating the earthquake catalog of the National Observatory of Athens Chouliaras G. 1 National Observatory of Athens, Institute of Geodynamics, P.O. Box 20048, 11810 Athens, Greece 23 06 2009 9 3 905 912 Copyright: © 2009 G. Chouliaras 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://nhess.copernicus.org/articles/9/905/2009/nhess-9-905-2009.html The full text article is available as a PDF file from https://nhess.copernicus.org/articles/9/905/2009/nhess-9-905-2009.pdf

The earthquake catalog of the National Observatory of Athens (NOA) since the beginning of the Greek National Seismological Network development in 1964, is compiled and analyzed in this study. The b-value and the spatial and temporal variability of the magnitude of completeness of the catalog is determined together with the times of significant seismicity rate changes. <br><br> It is well known that man made inhomogeneities and artifacts exist in earthquake catalogs that are produced by changing seismological networks and in this study the chronological order of periods of network expansion, instrumental upgrades and practice and procedures changes at NOA are reported. The earthquake catalog of NOA is the most detailed data set available for the Greek area and the results of this study may be employed for the selection of trustworthy parts of the data in earthquake prediction research.

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