Collaborative Proposal: Postseismic deformation of the Izmit-Duzce, Turkey earthquake sequence: implications for the mechanics of the earthquake cycle and rheology of the continent

合作提案：土耳其伊兹米特-迪兹杰地震序列的震后变形：对地震周期力学和大陆流变学的影响

• 批准号: 1246577
• 负责人: Robert Reilinger
• 金额: $ 16.3万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2016-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1246577&HistoricalAwards=false
• 关键词: Collaborative; Proposal; Postseismic; deformation; Izmit

The Izmit-Duzce earthquake sequence (M=7.4, 17/08/1999; M=7.2, 12/11/1999) offers a uniqueopportunity to answer long-standing, fundamental questions about the nature of the earthquake cycle(mechanics of strain accumulation and release), and the rheology of the crust and upper mantle. Thegeodetic data set we are developing for these earthquakes includes both a well-determined preearthquakevelocity field around the earthquake fault, and a network of GPS stations within the coseismicdeformation zone (near and far field) that captured the initial, rapid, and ongoing longer-termpostseismic deformation. This is one of the most complete geodetic records of deformation for any majorcontinental earthquake anywhere in the world.Interpretation of the geodetic record is facilitated by detailed seismic observations before, during,and following the earthquake sequence, field mapping of fault offsets, satellite image (SPOT) andgeodetic (InSAR) studies, and geologic studies of the 20th Century sequence of earthquakes thatpropagated along the North Anatolian Fault (NAF) from E to W fracturing almost the full 1200 km lengthof the fault (excluding the Marmara segment). Furthermore, the NAF has a long and well recordedhistorical seismic record extending back almost 2000 years that, along with the well-constrainedpaleoseismic record and recent geodetic observations, provides an extensive data set for testingearthquake models of continental faulting.In collaboration with our Turkish partners, we propose to use an extensive catalogue of availableGPS and InSAR data to constrain continuing deformation following the Izmit-Duzce earthquakesequence, and to extend our modeling effort to produce a quantitative description of the dynamics of theNAF system seismic cycle. The proposed research builds on our prior efforts (Ergintav et al., 2009; Hearnet al., 2009) that included analysis of 6.5 years of postseismic GPS observations (both continuous [CGPS]and survey [SGPS]) to characterize the temporal and spatial behavior of initial, and early postseismicmotions, and dynamic modeling for the initial 2.5-year period following the earthquake sequence. Inaddition, an important new constraint on postseismic deformation is provided by recent InSAR analysis(Cakir et al., 2012) that requires a re-evaluation of the role of afterslip along a substantial segment of thecoseismic fault late in the postseismic period, potentially with major implications for seismic hazards.The proposed research will provide an important set of observations on the natureof the earthquake cycle for a major continental strike-slip fault with direct implications for earthquakemechanics, estimating earthquake repeat times, crust and upper mantle rheology as a function of the stateof stress, and interaction between earthquake processes and regional tectonics. This case study provides information on the mechanics of continental strike-slip faults in general, including the San Andreas Fault, earthquake and tsunami hazards in the greater Istanbul area, and opportunities for international scientific collaboration.

IZMIT-DUZCE地震序列（M = 7.4，17/08/1999; M = 7.2，12/11/1999）提供了独特的pportunity，可以回答有关地震周期的长期存在的基本问题（应变积累和释放的机制）以及Croust and the Croust and the Croust and the Croust and the Croust和Upper Mantle。我们正在为这些地震开发的地理数据集包括地震断层周围的明确的预性预性磁场，以及CoseSissicdeformationformation区域内（近外和远场）内的GPS站网络，该网络捕获了初始，快速且持续不断的长期固定性粘膜粘膜。这是世界上任何主要地震的最完整的变形记录之一。对地震序列，期间和之后的详细地震观测，地震记录的解释促进Anatolian断层（NAF）从E到W骨折几乎将故障的1200公里长（不包括Marmara段）。此外，NAF具有较长且悠久的历史地震记录，延伸了近2000年，与良好的销售震荡记录和最近的大地测量观察一起，为大陆的测试模型提供了广泛的数据集，用于与我们的土耳其党的合作，我们建议使用可用的数据范围，并提出了一项可用的数据，我们建议使用的数据集，并在内izmit-duzce地震，并扩展了我们的建模工作，以产生对THNAF系统地震循环的动力学的定量描述。拟议的研究以我们先前的努力为基础（Ergintav等，2009; Hearnet al。，2009），其中包括分析6。5年的地震后GPS观察（连续[CGP]和调查[SGPS]），以表征初始和早期层次序列的初始和早期模型的时间和动态模型的时间和动态2.5年的时间范围。陷入困境，最近的Insar分析（Cakir等，2012）提供了对地震后变形的重要新限制，要求重新评估沿层后期的大部分层面的作用，在后期的后期，在后期的后期，潜在地对持续的范围进行了对地震危害的影响。对地震机力学的直接影响，估计地震重复时间，地壳和上地幔流变学作为状态压力的函数以及地震过程与区域构造之间的相互作用。该案例研究提供了有关大陆滑移断层机制的信息，包括大伊斯坦布尔地区的圣安德烈亚斯断层，地震和海啸危害，以及国际科学合作的机会。