NSFGEO-NERC: Latest Pleistocene-Holocene incremental slip record of the Kekerengu-Jordan fault system, northern South Island, New Zealand

NSFGEO-NERC：新西兰南岛北部 Kekerengu-Jordan 断层系统最新更新世-全新世增量滑移记录

• 批准号: 1759252
• 负责人: James Dolan
• 金额: $ 35.41万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1759252&HistoricalAwards=false
• 关键词: NSFGEO; NERC; Latest; Pleistocene; Holocene

The standard model for rupture of large earthquakes along strike-slip faults is that the slip that generates the earthquake occurs on a single surface. The November 14, 2016 Kaikoura, New Zealand, magnitude 7.8 earthquake shook up this thinking about fault slip behavior. In what initially seemed to be an event resulting from slip along a single fault, turned out to be more complex with slip jumping from one fault to another within a network of faults called the Marlborough fault system. In this project, a research team from the University of Southern California, United Kingdom, and New Zealand will use a variety of cutting-edge methods to reconstruct the slip and paleo-earthquake history of one of the Marlborough fault system faults, the Kekerengu-Jordan fault system, which experienced about 12 meters of slip in the 2016 event. Data collected in this project would be used in conjunction with data from other faults in system to better understand earthquake recurrence rates and, more importantly, the temporal and spatial linkage between these faults, something that was clearly not well understood before the Kaikoura earthquake. Understanding the threat from major earthquakes to an increasingly urbanized American population is of critical importance for facilitating proactive and efficient measures to reduce future loss of life and property. Yet understanding of what to expect in terms of the occurrence of large earthquakes in time and space remains severely limited by the current lack of information about how entire systems of inter-connected earthquake faults store and release seismic energy in large, potentially damaging earthquakes. Comprehensive data sets, such as those that will result from this project will reveal how the major faults in a fault system interact with one another to generate potentially damaging earthquakes. These kinds of observations will, in turn, allow for better forecasting of what to expect from similar fault networks in the United States, particularly in earthquake-prone California, but more generally for all of the major faults that underlie large parts of the country. The project has potential to benefit society or advance desired societal outcomes through full participation of women in STEM, increased public scientific literacy with STEM through outreach activities, improved well-being of individuals in society by better understanding of fundamental processes underlying earthquakes that would improve the capability to model earthquake hazards, development of a diverse, globally competitive STEM workforce through graduate student training, and increased partnerships through international collaboration.The primary aim is to advance understanding of the collective behavior of regional fault networks, particularly the importance of emergent phenomena such as earthquake clusters and strain transients that may not be expected in the current understanding of earthquake physics and that are not accounted for in current seismic hazard assessment strategies. Mounting evidence suggests that the occurrence of large earthquakes on both single faults and fault systems is not a random process, with increasing observations of temporal and spatial earthquake clustering, changes in incremental fault slip rates, variations in fault loading rates, and potentially coordinated waxing and waning of slip on mechanically complementary faults in regional fault systems. Although a thorough understanding of both the causes and generality of such phenomena is of basic importance for fault mechanics, earthquake physics, and more accurate assessment of seismic hazard, evaluation of the importance of these behaviors has been severely data limited. In particular, there are too few comprehensive paleo-earthquake and incremental fault slip rate data sets to fully assess the collective behavior of major plate-boundary fault systems in time and space. This study focuses on the Pacific-Australia plate boundary in northern South Island New Zealand in order to document a complete latest-Pleistocene-Holocene (15 ka-present) record of incremental plate boundary slip encompassing all major structures in the system. The research team will build on previous work by developing robust records for the Kekerengu-Jordan fault system, an 85-km-long, oblique reverse-dextral fault system, which is the fastest-slipping fault in the onshore part of the plate boundary at 25-30 mm/year. Slip on the Kekerengu-Jordan fault system generated most of the moment release in the 2016 Mw=7.8 Kaikoura earthquake. The new post-IR IRSL225 luminescence dating protocol will be used at key sites on the Kekerengu-Jordan fault system, and at additional sites located with the new post-earthquake high-resolution lidar data collected by the New Zealand government. This new luminescence dating technique provides precise and reproducible dating of carbon-poor sediments typical of those in the study area with precision roughly equal to that of radiocarbon dating. Combining incremental fault offsets and trench observations with post-IR IRSL225 dating, and carbon-14 analysis will yield detailed fault slip rates and earthquake ages along the fault system spanning individual ruptures back though several dozen earthquakes. In conjunction with existing data sets from both the onshore and offshore faults, including the subduction megathrust that underlies the Kekerengu-Jordan fault system, the research will facilitate a comprehensive, system-level analysis of plate-boundary strain release through time and space during latest Pleistocene-Holocene time.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

大地震沿着滑滑断层破裂的标准模型是，产生地震的滑动发生在单个表面上。 2016年11月14日，新西兰Kaikoura，幅度7.8地震震惊了这种关于断层行为的想法。最初似乎是沿着单个故障滑倒导致的事件，事实证明，在称为Marlborough故障系统的故障网络中，滑道从一个故障跳到另一个故障时更为复杂。在这个项目中，来自南加州大学，英国和新西兰的一个研究团队将使用各种尖端方法来重建马尔伯勒故障系统故障之一的滑道和古Quake史，Kekerengu-Jordan故障系统，在2016年活动中经历了大约12米的滑移。该项目中收集的数据将与系统中其他故障的数据结合使用，以更好地了解地震复发率，更重要的是，这些断层之间的时间和空间链接，这在Kaikoura地震之前显然不太了解。了解主要地震对日益城市化的美国人口的威胁对于促进积极主动，有效的措施以减少未来的生命和财产丧失至关重要。然而，由于目前缺乏有关如何在大型，潜在破坏的地震中释放地震能量的整个系统如何存储整个系统如何存储整个系统的信息，因此了解时间和空间中发生大地震的期望仍然受到严重限制。全面的数据集，例如由该项目导致的数据集将揭示故障系统中的主要故障如何相互作用，从而产生潜在的破坏地震。反过来，这些观察结果将可以更好地预测到美国类似断层网络的期望，尤其是在易于地震的加利福尼亚州，但更普遍地是为了全国大部分地区的所有主要断层。 The project has potential to benefit society or advance desired societal outcomes through full participation of women in STEM, increased public scientific literacy with STEM through outreach activities, improved well-being of individuals in society by better understanding of fundamental processes underlying earthquakes that would improve the capability to model earthquake hazards, development of a diverse, globally competitive STEM workforce through graduate student training, and increased partnerships through international collaboration.The primary aim is to advance understanding of the区域断层网络的集体行为，尤其是在当前对地震物理学的理解中可能无法预期的新兴现象的重要性，例如地震簇和应变瞬变，并且在当前的地震危害评估策略中没有考虑到。越来越多的证据表明，单个故障和断层系统上发生大地震的发生并不是一个随机过程，随着时间和空间地震聚类的观察到越来越多的观察结果，逐步断层滑动速率的变化，故障负载速率的变化以及潜在的配位蜡以及在区域故障系统中的互联断层衰减的可能性变化。尽管对这种现象的原因和普遍性的透彻理解对于断层力学，地震物理学以及对地震危害的更准确评估至关重要，但是评估这些行为的重要性的评估受到了严格的数据限制。尤其是，很少有全面的古电子和渐进的断层滑移率数据集，无法充分评估时间和空间中主要板块结合断层系统的集体行为。这项研究的重点是新西兰北部北部岛上的太平洋 - 澳大利亚板块边界，以记录完整的最新新世 - 近代（15 ka-stres）记录，记录了涵盖系统中所有主要结构的增量板边界滑移。研究团队将通过为Kekerengu-Jordan故障系统开发出色的记录，这是一个85公里长的倾斜反向止损故障系统，这是25-30毫米/年的盘子边界上最快的断层。在Kekerengu-Jordan断层系统上滑倒在2016 MW = 7.8 Kaikoura地震中产生的大部分时间释放。新的后IR IRSL225发光约会协议将在Kekerengu-Jordan断层系统的关键站点以及带有新西兰政府收集的新的地点高分辨率激光雷达数据的其他站点上使用。这种新的发光约定技术提供了研究区域中典型的碳贫气沉积物的精确和可再现的年代，其精度大致等于放射性碳年代。将增量断层偏移和沟槽观测与后IR IRSL225约会结合在一起，以及碳14分析将产生详细的断层滑移速率和地震年龄，沿断层系统跨越了单个破裂，但通过数十次地震而产生。结合来自陆上和近海故障的现有数据集，包括基于Kekerengu-Jordan断层系统的俯冲巨型托架，该研究将促进对板型释放的全面，系统级别的分析，该分析在最新的全新元素奖励期间通过nission and the Nevions necation and dechation and dechiation artive and dechation。基金会的智力优点和更广泛的影响评论标准。