EAGER: Geologic Evidence of Tsunamis originating from the Japan Trench's Southern Segment

EAGER：海啸源自日本海沟南段的地质证据

• 批准号: 1357722
• 负责人: Benjamin Horton
• 金额: $ 1.92万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1357722&HistoricalAwards=false
• 关键词: EAGER; Geologic; Evidence; Tsunamis; originating

In the wake of the 2011 Tohoku-oki tsunami, studies modelling rupture scenarios for the Japan Trench have identified areas of uncertainty, particularly along the southern segment. The accuracy of these seismic models and the understanding of fault movement along the southern Japan Trench can be greatly improved by locating and mapping prehistoric tsunamis deposits. Records of tsunamis developed from the sedimentary deposits they leave behind, improve our understanding by expanding the age range of events available for study. This EAGER research project, carried out by scientists from the University of Pennsylvania and the Geological Survey of Japan, aims to locate geologic evidence of past tsunamis originating from the southern segment of the Japan Trench, which to date remains undocumented. The study will investigate the beach ridges and coastal ponds of Chiba region of Japan using the state-of-the-art litho-, bio-, and chronostratigraphical techniques. The research is highly exploratory in nature since, as of yet, geologic evidence of paleo-tsunamis in this region has been found.The importance of understanding the timing and magnitude of tsunamis originating from the Japan Trench was highlighted by the unexpected Mw 9.0 Tohoku-oki event in 2011. Despite generating the largest instrumental record of an earthquake, very little is known about the Japan Trench, particularly its southern segment near Tokyo. The establishment of a recurrence interval for tsunami generating earthquakes improve assessments of natural hazards to the Greater Tokyo Area, the largest metropolitan area in the world. This research will provide important new information concerning the uncertainty surrounding long-term earthquake patterns, not only for the Japan Trench, but also for other locations such as the Pacific coast of North America, Chile and Indonesia.

2011 年东北冲海啸之后，对日本海沟破裂情景进行建模的研究发现了不确定的区域，特别是南部地区。通过定位和绘制史前海啸沉积物，可以大大提高这些地震模型的准确性以及对日本南部海沟断层运动的理解。海啸的记录是从海啸留下的沉积物中发展而来的，通过扩大可供研究的事件的年龄范围来提高我们的理解。这项 EAGER 研究项目由宾夕法尼亚大学和日本地质调查局的科学家开展，旨在寻找源自日本海沟南段的过去海啸的地质证据，但迄今为止，该海啸尚未有记录。该研究将利用最先进的岩石、生物和年代地层技术来调查日本千叶地区的海滩山脊和沿海池塘。这项研究本质上是高度探索性的，因为迄今为止，该地区古海啸的地质证据已经被发现。意外的兆瓦 9.0 东北海啸突显了了解起源于日本海沟的海啸的时间和强度的重要性。 2011 年发生的大地震。尽管产生了最大的地震仪器记录，但人们对日本海沟，特别是其靠近东京的南段知之甚少。建立海啸引发地震的复发间隔可以改善对世界上最大的都市区大东京地区自然灾害的评估。这项研究将为日本海沟以及北美太平洋沿岸、智利和印度尼西亚等其他地区的长期地震模式的不确定性提供重要的新信息。