Abstract
The North Anatolian fault is a well-defined tectonic feature extending for 1400 km across Northern Turkey. The space-time distribution of seismicity and faulting of this zone has been examined with a particular emphasis on the identification of possible seismic gaps. Results suggest several conclusions with respect to the temporal and spatial distribution of seismicity. First, the earthquake activity appears not to be stationary over time. Periods of high activity in 1850–1900 and 1940 to the present bracket a period of relatively low activity in 1910–39. Second, there appears to have been a two-directional migration of earthquake epicenters away from a central region located at about 39°E longitude. The migration to the west has a higher velocity (>50 km/yr) than the migration to the east (≤10km/yr). The faulting associated with successive earthquakes generally abuts the previous rupture. Some existing gaps were filled by later earthquakes.
At present there are two possible seismic gaps along the North Anatolian fault zone. One is at the western end of the fault, from about 29° to 30°E. Unless this is a region of ongoing aseismic creep, it could be the site of a magnitude 6 or greater earthquake. The other possible gap is at the eastern end, from about 42° to 43°E, to the west of the unexpected M=7.3 event of 24 November 1976.
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References
Allen, C. R. (1965),Transcurrent faults in continental areas, Phil. Trans. R. Soc. Lond.A258, 82–89.
Allen, C. R. (1969),Active faulting in northern Turkey, Contr. No. 1577, Div. Geol. Sic., Calif. Inst. Tech.32.
Allen, C. R. (1975),Geological criteria for evaluating seismicity, Bull. Geol. Soc. Am.86, 1041–1057.
Alsan, E., Tezucan, L. andBåth, M. (1975),An earthquake catalog for Turkey for the interval 1913–1970, Rept. 7-75, Kandilli Obs., Instanbul and Seismological Inst., Uppsala.
Alsan, E., Tezucan, L. andBåth, M. (1976),An earthquake catalog for Turkey for the interval 1913–1970, Tectonophysics31, 13–20.
Ambraseys, N. N. (1970),Some characteristic features of the North Anatolian fault zone, Tectonophysics9, 143–165.
Ambraseys, N. N. andZatopek, A. (1969),The Mudurnu Valley, West Anatolian, Turkey, earthquake of 22 July 1967, Bull. Seism. Soc. Am.59, 521–589.
Arpat, E. andSaroglu, F. (1972),The East Anatolian fault system: Thoughts on its development, Bull. Mineral Res. Expl. Inst. Turkey78, 33–39.
Arpat, E., Saroglu, F. andIz, H. B. (1977),1976 Caldiran earthquake, Yeryuvari ve Insan2, 29–41.
Båth, M.,Introduction to Seismology (John Wiley and Sons, New York, 1973).
Brune, J. N. (1968),Seismic moment, seismicity and rate of slip along major fault zones, J. Geophys. Res.73, 777–784.
Canitez, N. andToksöz, M. N. (1978),Strain release and earthquake occurrences along the North Anatolian fault zone, Tectonophysics, in press.
Dewey, J. W. (1976),Seismicity of Northern Anatolia, Bull. Seism. Soc. Am.66, 843–868.
Ergin, K., Guolu, U. andUz, Z. (1967),A catalog of earthquakes for Turkey and surrounding areas, Tech. Univ. Istanbul Mining Eng. Fac., Publ. No. 24, 74 pp.
Gutenberg, B. andRichter, C. F. Seismicity of the Earth and Associated Phenomena (Princeton University Press, 1949).
Karnik, V.,Seismicity of the European Area, Part 1 (Academic Praha, Publishing House of the Czechoslovak Academy of Sciences, 1968).
Ketin, I. (1968),Relation between general tectonic features and the main earthquake region of Turkey, Bull. Mineral Res. Expl. Inst.71, 63–67.
Ketin, I. (1969),On the North Anatolian fault, Bull. Mineral Res. Expl. Inst.72, 1–26.
Ketin, I. (1976),A comparison between San Andreas and N. Anatolian faults, Bull. Turkish Geol. Soc.19, 149–154 (in Turkish).
McKenzie, D. P. (1972),Active tectonics of the Mediterranean region, Geophys. J. R. astr. Soc.30, 109–185.
Mogi, K. (1968),Migration of seismic activity, Bull. Earthquake Res. Inst., Tokyo Univ46, 53–74.
North, R. C. (1977),Seismic moment, source dimension and stresses associated with earthquakes in the Mediterranean and Middle East, Geophys. J. R. astr. Soc.48, 137–161.
North, R. C. (1974),Seismic slip rate in the Mediterranean and Middle East, Nature252, 560–563.
Richter, C. F.,Elementary Seismology (W. H. Freeman and Co., San Francisco, 1958).
Sengor, A. M. C., The North Anatolian fault: its age, offset and tectonic significance, to be published, 1978.
Seymen, I. andAydin, A. (1972),The Bingöl earthquake fault and its relation to the North Anatolian fault zone, Bull. Mineral Res. Expl. Inst. Turkey79, 1–8.
Smith, S. W. andVan de Lindt, W. (1969),Strain adjustments associated with earthquakes in Southern California, Bull. Seism. Soc. Am.54, 1569–1589.
Tatar, Y. (1975),Tectonic structures along the North Anatolian fault zone, northeast of Refalize (Erzincan), Tectonophysics29, 401–410.
Toksöz, M. N., Arpat, E. andSaroglu, F. (1977),East Anatolian earthquake of 24 November 1976, Nature270, 423–425.
Wallace, R. E. (1968),Earthquake of August 19, 1966, Varto area, Eastern Turkey, Bull. Seism. Soc. Am.58, 11–45.
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Toksöz, M.N., Shakal, A.F. & Michael, A.J. Space-time migration of earthquakes along the North Anatolian fault zone and seismic gaps. PAGEOPH 117, 1258–1270 (1979). https://doi.org/10.1007/BF00876218
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DOI: https://doi.org/10.1007/BF00876218