Collaborative Research: Paleoseismic Evidence of Earthquakes and Tsunamis along the Southern Part of the Japan Trench

合作研究：日本海沟南部地震和海啸的古地震证据

• 批准号: 1624551
• 负责人: Benjamin Horton
• 金额: $ 14.34万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1624551&HistoricalAwards=false
• 关键词: Collaborative; Research; Paleoseismic; Evidence; Earthquakes; Collaborative; Research; Paleoseismic; Evidence; Earthquakes

There is an extensive instrumental, historical, and geological record of tsunamigenic-earthquakes originating from the northern and middle parts of the Japan Trench that documents the last several thousand years of earthquakes and tsunamis, including the magnitude 9 Tohoku earthquake in 2011. This earthquake ruptured five segments along the northern and middle parts of the Trench, but failed to rupture through the southern part, which is near metropolitan Tokyo. The seismic risk for this portion of the trench is uncertain because of the possibility that stress transferred southwards during the 2011 earthquake and that this part of the subduction zone is locked. Furthermore, the instrumental and historical record is sparse with only one tsunamigenic-earthquake on record (CE 1677 Empo earthquake) and lack of long-term geological data. A research team from University of Southern Mississippi and Rutgers University in collaboration with Japanese researchers will employ an innovative combination of field, laboratory (sedimentary, microfossil, and radiometric analyses), statistical, and modeling techniques to a series of possible tsunami deposits in order to determine the tsunami and earthquake history of the southern Japan Trench, data which is very important for anticipating future disasters. Besides providing an improved understanding of seismic risk in the Tokyo region, additional benefits to society include improved STEM education though outreach to middle school students and development of a globally competitive STEM workforce through training of graduate and undergraduate students and post-doctoral fellow mentoring.The detection and characterization of tsunami deposits preserved in coastal sediments provides a long-term record of past earthquakes. This project focuses on three candidate-tsunami sands that are preserved in coastal rice fields in the Kujukuri beaches, a strand plain located on the Boso Peninsula approximately 50 km east of Tokyo. The identification of tsunami deposits using proxy analyses (grain size and microfossil), with Bayesian age-depth models and tsunami simulation models, will resolve whether the southern part of the trench can produce future earthquakes that are similar in size as the 2011 Tohoku event. Well-constrained ages for each candidate tsunami will permit an accurate estimation of the shoreline position, and thus, inundation distance at the time of deposition. By integrating these changing shoreline positions into previously developed tsunami simulation models (e.g., 2011 Tohoku and CE 1677 Empo models), the research team will test whether previous middle/northern or southern trench ruptures could have deposited the tsunami sands on the Boso Peninsula.

源自日本沟渠的北部和中部的海啸 - 地震有广泛的工具，历史和地质记录，记录了最后几千年的地震和海啸，其中包括2011年的9幅度的Tohoku地震。东京大都会。这部分沟渠的地震风险不确定，因为在2011年地震期间，压力可能向南转移，并且俯冲带的这一部分被锁定。此外，工具和历史记录稀疏，只有一个有记录记录下的海藻 - 1677年empo地震），并且缺乏长期的地质数据。来自南密西西比大学和罗格斯大学与日本研究人员合作的研究团队将采用现场，实验室（沉积，微化石和放射测定分析），统计和建模技术的创新组合，并为一系列可能的海啸沉积物来确定日本南部的一系列可能的潜入。除了提供对东京地区地震风险的增进的了解外，对社会的额外好处还包括对中学生的宣传，以及通过培训研究生和本科生的培训以及在沿海沿海疾病中保存的长期唱片的表征，通过培训研究生和大学生的培训，并通过培训研究生和学科生的培训来发展全球竞争性的STEM劳动力。该项目着重于三个候选海啸砂，这些沙子砂被保存在库朱库里海滩的沿海稻田中，库朱库里海滩是位于东京以东约50公里的波索半岛上的一块平原。使用代理分析（晶粒尺寸和微化石）鉴定海啸沉积物，具有贝叶斯年龄深度模型和海啸模拟模型，将解决沟槽的南部部分是否可以产生与2011年Toohoku事件的未来地震。每个候选海啸的受良好约束年龄将允许对沉积时的海岸线位置进行准确的估计，从而可以准确地估算淹没距离。通过将这些不断变化的海岸线位置整合到先前开发的海啸模拟模型（例如，2011年Tohoku and CE 1677 EMPO模型）中，研究团队将测试以前的中/北部或南部沟渠破裂是否可以将海啸砂沉积在Boso Peninsula上。