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1999年8月17日,在北安纳托利亚断层上伊斯坦布尔以东100 km的伊兹米特市附近发生了7.4级的破坏性大地震。这个1600 km长的板块边界(Barka,1992,1999)以平均为2～3cm/a的速率滑动(Reilinger,et al,1997;Hubert,1998;hrmijo,et al,1999),历史上为多次破坏性地震的发生地点(Ambraseys,1970;Ambraseys and Finkel,1991)。仅20世纪沿此断层就破裂了900 km的长度(Ambraseys,1970)。利用地震产生的应力变化的模型(King,et al,1994),结合活动断层分布图分析,预测的1999年伊兹米特地震的震中区确实是大地震发生的可能位置(Nalbant,et al,1998;stein,et al,1997)。本文展示证据说明,1999年的地震本身显著改变了先前地震断层相互作用产生的应力分布(Nalbant,et al,1998;stein,et al,1997)。我们的新应力模型考虑了此地区自1700年后发生的震级大于6的所有地震(Ambraseys,et al,1991),以及由GPS数据约束的地震之间的长期应力变化(straub,et al,1997)。这些模型提供了北安纳托利亚断层长期时空行为的一致图象,并指出在今后数十年内,伊斯坦布尔以南的马尔马拉海之下将可能发生震级等于或大于伊兹米特地震的两个地震。
On August 17, 1999, a magnitude 7.4 devastating earthquake near Izmit, 100 km east of Istanbul on the Northern Anatolian Fault, occurred. This 1600 km long plate boundary (Barka, 1992, 1999) slides at an average rate of 2-3cm / a (Reilinger, et al, 1997; Hubert, 1998; hrmijo, et al, 1999) The site of destructive earthquakes (Ambraseys, 1970; Ambraseys and Finkel, 1991). In the 20th century alone, the fault ruptured for a length of 900 km (Ambraseys, 1970). Using the model of stress-induced changes in earthquakes (King et al., 1994) and the analysis of active fault maps, it is predicted that the epicentral region of the 1999 Izmit earthquake is a likely location for large earthquakes (Nalbant, et al. 1998; stein, et al, 1997). This article shows evidence that the 1999 earthquake itself significantly changed the stress distribution resulting from previous seismic fault interactions (Nalbant, et al, 1998; Stein, et al, 1997). Our new stress model accounts for the long-term stress changes in all the earthquakes (Ambraseys, et al., 1991) and the earthquakes constrained by GPS data since 1700 in the region (straub, et al., 1997 ). These models provide a consistent picture of the long-term spatiotemporal behavior of the North Anatolia fault and point out that a magnitude of magnitude equal to or greater than that of the Izmit earthquake may occur below the Marmara Sea south of Istanbul in the coming decades Two earthquakes.