High-resolution imaging of the North Anatolian Fault Zone in the broader Marmara region from near-fault seismic recordings

根据近断层地震记录对更广泛的马尔马拉地区北安纳托利亚断层带进行高分辨率成像

• 批准号: 341428181
• 负责人: Professor Dr. Marco Bohnhoff
• 金额: --
• 依托单位: Institute of Geophysics
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/341428181?language=en
• 关键词: resolution; imaging; North; Anatolian; Fault

The North Anatolian Fault Zone (NAFZ) is the most active plate-bounding strike-slip fault in Europe and has produced numerous large devastating earthquakes in historic times. A series of large earthquakes starting in 1912 has activated the entire 1200km-long fault zone except for the Marmara section that is located in direct vicinity to the 15-million population center of Istanbul and currently overdue for a M>7 event.We aim at imaging the horizontal and vertical structures, identify and investigate bimaterial interfaces and low-velocity damage at the NAFZ in NW Turkey using Fault Zone Head Waves along with trapped and reflected waves, direct body waves and near-fault anisotropy. The results will substantially contribute to an improved seismic hazard assessment for this key region based on refined determination of the relevant fault-zone structure and physics along the NAFZ. We will also apply a recently introduced passive imaging technique that allows making use of converted phases and their inversion together with synthetic waveforms. Our study will focus on three key sections of the NAFZ in the Marmara region, (1) the Princes Island segment below the eastern Sea of Marmara where the ICDP-driven GONAF observatory has recently been implemented, (2) the Ganos fault further to the west that last ruptured in a M7.4 earthquake in 1912, and (3) the combined Izmit-Düzce rupture that produced two consecutive M>7 earthquakes in 1999. We will make use of extensively seismic waveform recordings that are either already available (Princes Islands segment, Izmit-Düzce) or will be acquired in the frame of a scheduled field campaign (Ganos).The high-resolution fault-zone images to be obtained in the here proposed study are expected to contribute to fundamental aspects of earthquake and fault dynamics on the NAFZ, including the mode and propagation direction of earthquake ruptures, triggering and effective constitutive laws. In particular the results will also provide a detailed characterization and subsequent seismic hazard for the easternmost portion of the Marmara section of the NAFZ that is expected to produce a major (M>7) earthquake in the near future.

北安纳托利亚断层区（NAFZ）是欧洲最活跃的板滑滑断层，在历史时期造成了许多大型毁灭性地震。从1912年开始，一系列大地震激活了整个1200公里长的断层区，除了位于伊斯坦布尔1500万人口中心的Marmara部分，目前曾在M> 7事件中逾期。我们的目标是通过对水平和垂直型损坏进行成像，并在fanke中识别和垂直损坏。以及反射的波浪，直接的身体波和近门见。基于对NAFZ沿NAFZ相关的断层区结构和物理学的精致确定，该结果将大大导致该关键区域的地震危害评估。我们还将应用最近引入的无源成像技术，该技术允许使用转换相及其反转以及合成波形。 Our study will focus on three key sections of the NAFZ in the Marmara region, (1) the Princes Island segment below the Eastern Sea of ​​Marmara where the ICDP-driven GONAF observationy has recently been implemented, (2) the Ganos fault further to the west that last ruptured in a M7.4 earthquake in 1912, and (3) the combined Izmit-Düzce rupture that produced two consecutive M>7 1999年的地震。我们将利用已经可用的广泛的地震波形记录（王子岛段，izmit-düzce），或者将在预定的野外活动（Ganos）的框架内获取。地震破裂，触发和有效的本构法。特别是，结果还将为NAFZ的Marmara部分的最东端提供详细的表征和随后的地震危害，该危险预计在不久的将来会引起重大（M> 7）地震。