Temporal and three dimensional spatial analysis of earthquake activity between 1970 and 2010 along the North Anatolian Fault Zone, Turkey

Abstract

Characteristics of seismic activity from 1970 to 2010 along the North Anatolian Fault Zone (NAFZ) are analyzed to make a statistical assessment by using the Gutenberg-Richter b-value, seismic quiescence Z-value, fractal dimension Dc-value, and spatial, temporal and magnitude distributions. Magnitude completeness, Mc, changes between 2.7 and 2.9 in all parts of the NAFZ. Frequency-magnitude distribution of the earthquakes is well represented by the Gutenberg-Richter law with a b-value typically close to 1. A strong decrease in temporal distribution of b-value is observed before the great main shocks. Dc-values are relatively large and the seismic activity is more clustered at larger scales for all parts of the NAFZ. From the standard normal deviate Z-value test, eight significant anomalous zones are centered at 41.08ºN-28.58ºE (around Silivri), 41.47ºN-29.51ºE (in the Black Sea), 40.69ºN-29.78ºE (including Izmit), 40.26ºN-26.46ºE (around Gelibolu, Canakkale), 40.59ºN- 31.03ºE (including Duzce fault), 40.86ºN-35.30ºE (around Amasya), 39.48ºN-39.74ºE (around Erzincan), and 39.06ºN-40.50ºE (around Bingol).