EAR-PF: SPATIAL AND TEMPORAL VARIABILITY OF COSEISMIC SUBSIDENCE ALONG THE CASCADIA SUBDUCTION ZONE

EAR-PF：卡斯卡迪亚俯冲带同震沉降的时空变化

• 批准号: 1624795
• 负责人: Tina Dura
• 金额: $ 8.7万
• 依托单位: Dura Cristina
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1624795&HistoricalAwards=false
• 关键词: EAR; PF; SPATIAL; TEMPORAL; VARIABILITY

Dr. Cristina Dura has been granted an NSF EAR Postdoctoral Fellowship to carry out research and education plans at Humboldt State University. This investigation will expand the resolution of subsidence due to seismic events along the Cascadian margin in both space and time. This information is critical for the assessment of seismic and tsunami hazards along the Pacific coast in the USA. Dr. Dura will use computer modeling based on diatom abundance to estimate subsidence along the West Coast. The study will consist of three components: (1) expand regional modern diatom dataset from the coasts of southern Washington, Oregon, and northern California to better characterize the vertical zonation of diatoms in a range of tidal environments. This information will be used to infer ecological niches of fossil diatom assemblages in cores; (2) develop a new diatom-based computational model that will reduce errors on subsidence estimates by ~28% compared to previous models; and (3) use this information to understand the spatial and temporal distribution of earthquakes along the Cascadia subduction zone. The education plan will entail developing teaching materials for K12 schools, participating in teacher workshops, creating an online tsunami curriculum to accompany a children's book, and outreach events for the community through local community groups.Accurate and precise estimates of coseismic subsidence over multiple earthquake cycles are critical to understanding the patterns, timing, and magnitude of strain accumulation and release during past earthquakes. Dr. Dura will employ new Bayesian diatom-based transfer functions to estimate coseismic subsidence, and improve upon the accuracy of existing foraminifera-based transfer functions. New estimates of coseismic subsidence in multiple cores at four sites spanning over 600 km of the Cascadia subduction zone will be used to characterize and correlate earthquakes along strike and distinguish rupture lengths and earthquake magnitudes over the past 2000-4000 years. The high-precision subsidence estimates will be incorporated into 3-D elastic dislocation models to produce more realistic (heterogeneous vs. segmented) rupture models that will help improve future earthquake and tsunami hazard assessments. Using a modern diatom dataset and application of a new Bayesian diatom-based transfer function will advance quantitative microfossil-based techniques by significantly increasing the accuracy and precision of coseismic subsidence estimates at Cascadia.

克里斯蒂娜·杜拉（Cristina Dura）博士已获得NSF耳朵博士后奖学金，以在洪堡州立大学执行研究和教育计划。这项调查将扩大由于时空和时间上卡斯卡德式边际沿卡斯卡德式沿线的地震事件而导致的沉降解决。该信息对于评估美国太平洋海岸沿线的地震和海啸危害至关重要。 Dura博士将根据硅藻的丰度使用计算机建模来估计西海岸沿线的沉降。该研究将由三个组成部分组成：（1）从华盛顿南部，俄勒冈州和北加州沿海扩展区域现代硅藻数据集，以更好地表征硅藻在一系列潮汐环境中的垂直分区。该信息将用于推断岩心的化石硅藻组合的生态位； （2）开发一个新的基于硅藻的计算模型，与以前的模型相比，将对沉降估计的错误降低约28％； （3）使用此信息来了解卡斯卡迪亚俯冲带沿地震的空间和时间分布。 The education plan will entail developing teaching materials for K12 schools, participating in teacher workshops, creating an online tsunami curriculum to accompany a children's book, and outreach events for the community through local community groups.Accurate and precise estimates of coseismic subsidence over multiple earthquake cycles are critical to understanding the patterns, timing, and magnitude of strain accumulation and release during past earthquakes. Dura博士将采用新的基于贝叶斯硅藻的转移功能来估计Coseissic沉降，并提高现有基于有孔虫的转移功能的准确性。在过去2000 - 4000年中，将使用超过600公里的卡斯卡迪亚俯冲带（超过600 km）的Cascadia俯冲带的Coseis震中的新估计值来表征和相关地震，并区分破裂的长度和地震幅度。高精度沉降估计将被纳入3-D弹性错位模型中，以产生更现实的（异质与分段）破裂模型，这将有助于改善未来的地震和海啸危害评估。使用现代的硅藻数据集和新的基于贝叶斯硅藻的转移功能的应用将通过显着提高Cascadia的Coseissis sistives估计的准确性和精度来推动基于定量的微化石技术。