Collaborative Research: Permanent forearc strain partitioning in Northern Cascadia

这项工作首次详细描述了发生在加拿大不列颠哥伦比亚省南部活跃的陆地浅层断层上的过去地震的行为。该研究具有重要的社会效益，包括为不列颠哥伦比亚省温哥华岛和美国华盛顿西北部人口稠密地区的地震灾害评估提供了所需的关键投入。这些类型的数据对于帮助制定公共政策是必要的，这些政策可以减少未来地震造成的生命和财产损失。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，培养具有全球竞争力的多样化STEM劳动力。该项目还支持两名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突出断层的断层运动学和全新世滑动历史，评估了板块几何形状和斜辐合在北卡斯卡迪亚弧前变形产生中的作用。通过基岩填图和构造分析、第四纪偏移沉积的地表填图和古地震沟勘探，该研究正在验证新发现的活动地壳断层对平行于板块走向的相对板块运动分量的活动造山斜弯曲的影响。这项工作首次记录了一组断裂的第四纪活动，这些断裂以前被认为是始新世最后一次活动，并提供了检验板块边界应变划分模型所必需的基本运动学和滑动历史数据。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.