Coupling Between the 1999 M7+ Ruptures in Turkey as Illuminated by Small Earthquakes

建议摘要EAR-0087798(PH#48X)标题：1999年土耳其7级以上破裂之间的耦合，如小地震所示PI：L.Seeber和J.G.Armbrster，Lamont-Doherty地球观测站1999年8月17日MW7.4 Kocaeli(伊兹米特)地震之后，1999年11月12日发生MW7.2 Duzce地震，将第一次地震的破裂范围向东扩展。从第一次地震后1周到第二次地震后3个月，我们部署了覆盖这两个断裂交界处的10个台站网络，记录了约30,000次地震。我们正在领导一项工作，以形成一个单一的阶段数据集--来自在该研究地区部署的所有站点的数据集。然后，该目录将被用于绘制孕震断层图，监测区域弹性和孔隙弹性效应，并观察S波在空间和时间上的分裂。研究目标包括：1)了解次级断层和应变分配在北安纳托利亚转换西段复杂的张张构造体制中的作用，以及在序列中连续主震的触发；2)检验第二次主震是由第一次主震直接触发的，还是由在空间和时间上更接近破裂成核地点的应变事件触发的；3)研究S波分裂是否可以用来监测与断裂带的破裂和愈合有关的力学变化以及周围介质的应力变化。这项研究是与博加齐奇大学和伊斯坦布尔大学的坎迪利天文台合作进行的。

Abstract for proposal EAR-0087798 (PH #48x)Title: Coupling Between the 1999 M7+ Ruptures in Turkey as Illuminated by Small EarthquakesPI's: L. Seeber and J. G. Armbruster, Lamont-Doherty Earth ObservatoryThe Mw 7.4 Kocaeli (Izmit) earthquake on 17 August 1999 was followed on 12 November 1999 by the Mw 7.2 Duzce earthquake, which extended the rupture extent of the first earthquake eastward. We deployed a 10 station network covering the junction between these two ruptures from 1 week after the first earthquake to 3 months after the second, and recorded ~30,000 events. We are leading an effort to form a single phase-data set from all of the stations that were deployed in this study area. This catalog will then be used to map seismogenic faults, monitor regional elastic and poroelastic effects and observe S-wave splitting in space and time. Research objectives include:1) understanding the role of secondary faults and of strain partitioning in the complex transtensional tectonic regime of the western North Anatolian transform and in the triggering of successive mainshocks in the sequence; 2) testing whether the second mainshock was triggered directly by the first mainshock or whether it was triggered by a strain event closer in space and time to the site of rupture nucleation; and3) investigating whether S-wave splitting can be used to monitor mechanical changes associated with both rupture and healing of the fault zone and stress changes in the surrounding medium. This study is a collaboration with Kandilli Observatory of Bogazici University and Istanbul University.