Statistical Evaluation of Turkey Earthquake Data (1900-2015): A Case study

Yıl 2016, Cilt: 2 Sayı: 1, 14 - 36, 22.05.2016

Doğan Kalafat

Öz

In this study, Earthquake catalog of the events within the time period of 1900-2015 prepared by Boğaziçi University Kandilli Observatory and Earthquake Research Institute (KOERI) is analyzed.  The catalog consists of earthquakes occurred in Turkey and surrounding area (32^o-45^oN/23^o-48^oE). The current earthquake catalog data has been checked in two aspects; the time dependent variation and compliance for different regions. Specifically the data set prior to 1976 was found deficient. In total, 7 regions were evaluated according to the tectonic specifications and data set.  

In this study for every region original data were used without any change; b- values, a- values, Magnitude of completeness (Mc) were calculated. For the calculation of b- values focal depth was selected as h= 0-50 km. One of the important complications for the seismic catalogs is discriminating real (natural) seismic events from artificial (unnatural) seismic events. Therefore within the original current catalog events especially artificial quarry blasts and mine blasts have been separated by declustering and dequarry methods. Declustering process eliminates induced earthquakes especially occurred in thermal regions, large water basins, mine regions from the original catalogs. Current moment tensor catalog prepared by Kalafat, 2015 the faulting type map of the region was prepared. As a result, for each region it is examined if there is a relation between fault type and b- values. In this study, the hypothesis of the relation between previously evaluated and currently ongoing extensional, compression, strike-slip fault regimes in Turkey and b- values are tested one more time.

Anahtar Kelimeler

Catalog, explosion, b-value, magnitude compliteness (Mc)

Kaynakça

• Gephard, J.W. (1990). FMSI: A FORTRAN program for inverting fault/slickenside and earthquake focal mechanism data to obtain the original stress tensor, Comput.Geosci., 16, p.953-989.
• Gutenberg B, C.F. Richter (1944). Frequency of earthquakes in California, Bull. Seism. Soc. Am. 34, p.185–188.
• Gulia, L., S. Wiemer (2010). The influence of tectonic regimes on the earthquake size distribution: A case study for Italy, Geophysical Research Letters, Volume 37, Issue 10, May 2010, p1-6.
• Hedlin M.A.H, J.B. Minster , J.A. Orcutt (1990). An automatic means to discriminate between earthquakes and quarry blasts, Bull. Seismol. Soc. Am. 80, p.2143–2160.
• Horasan, G., A.B. Güney, A. Küsmezer, F. Bekler, Z. Oğütçü, N. Musaoğlu (2009). Contamination of seismicity catalogs by quarry blasts: an example from Istanbul and its vicinity, northwestern Turkey, J. Asian Earth Sci. 34(1), p.90–99.
• D., Kalafat (2015). Türkiye ve Çevresi Faylanma-Kaynak Parametreleri (MT) Kataloğu (1938-2015); A Cataloque of Source Parameters of Moderate and Strong Earthquakes for Turkey and its Surrounding Area (1938-2015), In preparation for publication, İstanbul.
• Kim W.Y., D.W. Simpson, P.G.Richards (1994). High-frequency spectra of regional phases from earthquakes and chemical explosions, Bull. Seism. Soc. Am. 84(5), p.1365–1386.
• Laura, G. (2010). Detection of quarry and mine blast contamination in European regional catalogues, Nat Hazards, DOI 10.1007/s11069-009-9426-8, s11069-009-9426-8.
• Michael, A.J. (1987b). Use of Focal Mechanism to Determine Stress: A control Study, Journal of Geophysical Research, 92, p. 357-368.
• Ogata, T., and K. Katsura (1993). Analysis of temporal and spatial heterogeneity of magnitude frequency distribution inferred from earthquake cataloques, Geophy. J. Int., 113, p.727-738.
• Okuda, S., T. Ouchi, and T. Terashima (1993). Deviation of Magnitude Frequency-Distribution of Earthquakes from Gutenberg-Richter Law-Detection of Precurory Anomalies Prior to Large Earthquakes, Phys. Earth Planet. Inter. 73 (3-4), p.229-238.
• Reasenberg, P. (1985). Second-order moment of central California seismicity: 1969–1982. J Geophys. Res. 90, p.5479–5495.
• Rydelek, P.A., and S. Sacks (1989). Testing the completeness of earthquake catalogs and the hypotesis of self-similarity, Nature 337, 251-253.
• Rydelek, P.A., and S. Sacks (1992). Comment on “Seismicity and detection/location treshold in the southern Great Basin seismic network” by Joan Gomberg, Journal of Geophysical Research, 97, p.15361-15362.
• Schorlemmer, D., S. Wiemer, M. Wyss (2005). Variations in earthquake-size distribution across different stress regimes, Nature 04094, Vol.437, p. 539-542.
• Schorlemmer, J. S. Woessner (2008). Probability of Detecing an Earthquake, BSSA Vol.98, No. 5, p. 2103-2117.
• Tormann, T., S. Wiemer, E. Hauksson (2010). Change of reporting rates in the Suthern Californian earthquake catalog, introduced by a new definition of Ml, BSSA, Vol.100, No.4, pp.1733-1742.
• Utsu, T. (1965). A method for determining the value of b in a formula log n=a-bM showing the magnitude frequency for earthquakes, Geophys. Bull. Hokkaido Univ., 13, p.99-103.
• Wessel, P., W.H.F. Smith (1995). New version of the generic mapping tools released. Eos Trans 76, p.329.
• Wiemer , S. and M. Wyss (1994). Seismic quesence before the Lenders (M=7.5) and Big Bear (M=6.5) 1992 earthquakes, Bull. Seism. Soc. Am. 84, p.900–916.
• Wiemer, S. and M. Wyss (1997). Mapping the frequency-magnitude distribution in asperities: and improved tecnique to calculate reccurence time?, J. Geophys. Res. 102, 1515-15128.
• Wiemer, S. and K. Katsumata (1999). Spatial variability of seismic parameters in aftershock zones, J. Geophys. Res., 104, 13, p.135-151.
• Wiemer, S., M. Baer (2000). Mapping and removing quarry blast events from seismicity catalogs.,Bull. Seism. Soc. Am. 90(2), p.525–530.
• Wiemer, S., M. Wyss (2000). Minimum magnitude of completeness in earthquake catalogs: examples from Alaska, the Western United States, and Japan. Bull. Seism. Soc. Am. 90(4), p.859–869.
• Wiemer, S. (2001). A software package to analyze seismicity: ZMAP. Seismol. Res. Lett. 72, p.373–382 .
• Wiemer, S. and Schorlemmer, D. (2007). ALM: An asperity-based likelihood model for California, Seismol. Res. Lett. 78, p.134–140.
• Woessner, J., S. Wiemer (2005). Assessing the quality of earthquake catalogues: estimating the magnitude of completeness and its uncertainty, Bull. Seism. Soc. Am. 95(2), p.684–698.
• Wüster, J. (1993). Discrimination of chemical explosions and earthquakes in Central Europe—a case study, Bull. Seism. Soc. Am. 83(4), p.1184–1212.
• Wyss, M. (1973). Toward a physical understanding of the earthquake frequency distribution, Geophy. J. Royal Astronomical Society, 31, p. 341-359.
• Zuniga F.R., M. Wyss (1995). Inadvertent changes in magnitude reported in earthquake catalogs: Influence on b-value estimates, Bull. Seism. Soc. Am. 85(6), p.1858–1866.
• Zuniga F.R., S. Wiemer (1999). Seismicity patterns: are they always related to natural