Collaborative Research: Permanent forearc strain partitioning in Northern Cascadia

合作研究：卡斯卡迪亚北部永久前弧应变分区

• 批准号: 2004684
• 负责人: Christine Regalla
• 金额: $ 25.14万
• 依托单位: Northern Arizona University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2004684&HistoricalAwards=false
• 关键词: Collaborative; Research; Permanent; forearc; strain

This work provides the first detailed characterization of the behavior of past earthquakes that have occurred on active, on-land, shallow faults in southern British Columbia, Canada. The research has important societal benefits that include providing key inputs needed for seismic hazard assessment in populated areas of Vancouver Island, British Columbia and northwestern Washington, USA. These types of data are necessary to help inform the development of public policy that can reduce the loss of life and property due to future earthquakes. Other important societal outcomes include contributions to STEM (science, technology, engineering and mathematics) education and the development of a diverse globally competitive STEM workforce by providing support for the training of graduate and undergraduate students. The project also supports the research of two female, early career scientists, and facilitates international collaborations between industry partners, policy makers, scientists and students. This project is evaluating the role of slab geometry and oblique convergence in the generation of forearc deformation in northern Cascadia by determining fault kinematics and the Holocene slip history of three prominent faults on Vancouver Island, British Columbia, Canada. Using a combination of bedrock mapping and structural analysis, surficial mapping of offset Quaternary deposits, and exploratory paleoseismic trenches, the research is testing the hypothesis that newly identified active crustal faults contribute to active oroclinal bending in response to the component of relative plate motion parallel to the strike of the slab. This work provides the first documentation of Quaternary activity on a set of faults previously thought to be last active in the Eocene, and provides fundamental kinematic and slip history data necessary to test models of plate boundary strain partitioning.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.

这项工作首次详细描述了加拿大不列颠哥伦比亚省南部活动的陆上浅断层上发生的过去地震的行为。该研究具有重要的社会效益，包括为温哥华岛、不列颠哥伦比亚省和美国华盛顿西北部人口密集地区的地震危险性评估提供关键投入。这些类型的数据对于帮助制定公共政策，减少未来地震造成的生命和财产损失是必要的。其他重要的社会成果包括对STEM（科学、技术、工程和数学）教育的贡献，以及通过为研究生和本科生的培训提供支持，发展具有全球竞争力的多元化STEM劳动力。该项目还支持两位女性早期职业科学家的研究，并促进行业合作伙伴，政策制定者，科学家和学生之间的国际合作。该项目通过确定加拿大不列颠哥伦比亚省温哥华岛三个主要断层的断层运动学和全新世滑动历史，评估板片几何形状和斜向会聚在北方卡斯卡迪亚弧前变形中的作用。利用基岩测绘和结构分析相结合的方法，对第四纪沉积物进行表层测绘，并对古地震槽进行勘探，这项研究正在检验一种假设，即新发现的活动地壳断层有助于活跃的造山带弯曲，以响应平行于板块走向的相对板块运动分量。这项工作提供了第一个文件的第四纪活动的一组故障以前被认为是最后活跃在始新世，并提供了基本的运动学和滑动历史数据所需的测试模型的板块边界应变partitioning.This奖项反映了NSF的法定使命，并已被认为是值得的支持，通过评估使用基金会的智力价值和更广泛的影响审查标准。

项目成果

Paleoseismic Trenching Reveals Late Quaternary Kinematics of the Leech River Fault: Implications for Forearc Strain Accumulation in Northern Cascadia

• DOI: 10.1785/0120200204
• 发表时间: 2021-04
• 期刊: Bulletin of the Seismological Society of America
• 影响因子: 3
• 作者: N. Harrichhausen;K. Morell;C. Regalla;S. Bennett;L. Leonard;Emerson M. Lynch;E. Nissen