Collaborative Research: RAPID: Response to the 29 July 2021 Chignik M8.2 Earthquake

合作研究：RAPID：对 2021 年 7 月 29 日奇格尼克 M8.2 地震的响应

• 批准号: 2147422
• 负责人: Jeffrey Freymueller
• 金额: $ 7.24万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2147422&HistoricalAwards=false
• 关键词: Collaborative; Research; RAPID; Response; 29

This RAPID award is a response to The July 2021 Chignik earthquake (M8.2) along the Alaskan Peninsula. This is the biggest earthquake in the US since 1965 (Rat Islands). It ruptured a segment of the megathrust offshore of the Alaska Peninsula, which last ruptured in 1938. The project deploys an integrated on-land observational field campaigns: geodesy to rapidly resurvey nearby monuments and document earthquake-related deformation, and seismology to deploy nearby instruments to record aftershocks. Understanding this earthquake will provide critical information for evaluating models of earthquake behavior and hence hazard among the planet’s largest earthquakes. Although only a small tsunami occurred, understanding better the rupture will allow for more realistic tsunami hazard assessments. The earthquake also provides ample opportunities for broadening participation in science, through rapidly making available data to the seismic and geodetic research communities. The project includes outreach to local schools, communities and governments and restarts a popular blog focused on geophysics in Alaska.The Chignik earthquake is a very rare example of a fault segment with two great earthquakes in the instrumental record, and is a critical locale to test theories of how seismic cycles work. The earthquake follows a pattern of along-strike segmentation previously documented between segments with large differences in locking behaviors and earthquake histories. The cause of this segmentation (or indeed of the variation in slip behavior more generally) remains uncertain, and collecting new data may elucidate the controlling mechanisms behind interseismic and coseismic rupture segmentation. Additionally, the earthquake provides an excellent laboratory to test theories of fault loading between segments and of our understanding of postseismic deformation. Almost precisely a year earlier, a M7.8 ruptured the abutting Shumagin segment to the west, indicating some possibility of triggering. That relationship can be explored, as well as the potential for bringing the next segment to the east closer to failure. The project takes advantage of decades of geodetic work on the Shumagins, Alaska Peninsula, and nearby islands, and the large 2018-9 GeoPRISMS-EarthScope-supported Alaska Amphibious Community Seismic Experiment. The project's outcome will be valuable in addressing questions related to the characteristics of earthquakes as articulated in the Earth in Time report from the National Academies of Science, Engineering and Medicine.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.

这一快速奖项是对2021年7月Chignik地震（M8.2）沿阿拉斯加半岛的回应。这是自1965年（大鼠岛）以来美国最大的地震。它破裂了阿拉斯加半岛的巨型近海，最后一次破裂，该部分于1938年破裂。该项目部署了一项集成的陆上观察现场活动：地理测量现象：迅速解决近线并记录地震相关的变形，并记录与地震的变形，以及在附近的床上录制的仪器，以录制后置的架子。了解这次地震将为评估地震行为模型的模型提供关键信息，从而在地球上最大的地震中危害。尽管只发生了一小片海啸，但更好地理解破裂将允许更现实的海啸危害评估。地震还为扩大科学的参与提供了足够的机会，通过迅速向地震和地球研究社区提供数据。该项目包括向当地学校，社区和政府的宣传，并重新启动了一个流行的博客，该博客侧重于阿拉斯加地球物理学。ChignikEarth地震是一个非常罕见的故障细分市场的例子，并具有两种伟大的地球记录，并且是测试地震cyces如何工作的理论的关键位置。地震遵循了先前在锁定行为和地震历史上差异很大的段之间记录的及时分割的模式。这种分割的原因（或实际上更广泛地差异的变化）仍然不确定，并且收集新数据可能会阐明跨界和coseismisic破裂分割背后的控制机制。此外，地震提供了一个极好的实验室，以测试段之间的故障负荷理论以及我们对后震后变形的理解。几乎恰好在一年前，M7.8破裂了西部的邻接Shumagin段，表明有些可能触发。可以探索这种关系，以及将下一个细分市场带到东方更接近失败的潜力。该项目利用了数十年来在舒马金，阿拉斯加半岛和岛屿附近的大地工作，以及大型的2018 - 9年地质主义者 - 地理位置 - 冰期支持的阿拉斯加两栖动物社区地震实验。项目的结果对于解决与美国国家科学，工程和医学学院在《地球时代》中阐明的地震特征有关的问题的问题将是有价值的。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子优点和更广泛的影响审查标准来评估的珍贵的支​​持。