Holocene records of Puerto Rico trench earthquakes and tsunamis

波多黎各海沟地震和海啸的全新世记录

• 批准号: 576695-2022
• 负责人: Pilarczyk, JessicaJE
• 金额: $ 1.82万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Alliance Grants
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=751099
• 关键词: Holocene; records; Puerto; Rico; trench

Coastlines from the Caribbean northward to the U.S. and Canadian Atlantic seaboard are susceptible to marine inundation by hurricanes and tsunamis. Potential sources of tsunami inundation include local (Puerto Rico trench) and far-field earthquakes. The historical record identifies far-field events, but no notable tsunamis originating from the Puerto Rico trench. It remains unclear whether outer rise or thrust ruptures, and their subsequent tsunamis, pose a greater risk to the western Atlantic. An outer rise rupture is not expected to generate any land-level change at Anegada, British Virgin Islands and is not considered to produce a large earthquake or tsunami. On the contrary, models indicate that a thrust earthquake scenario will generate 50 cm of coseismic subsidence and a subsequent tsunami that would inundate coastal areas stretching from the islands of the Caribbean to eastern Canada. To address this knowledge gap, Dr. Jessica Pilarczyk (Simon Fraser University) and Dr. Davin Wallace (University of Southern Mississippi) will apply an innovative combination of field, laboratory, statistical, and modelling techniques to a pre-Columbian sand sheet previously identified as possibly originating from a Puerto Rico trench tsunami. These methods will be applied to test the source of past ruptures along the Puerto Rico trench and answer questions about the possible magnitude of earthquakes and intensity of tsunami waves that can be expected in the future. An enhanced understanding of future earthquakes and tsunamis will allow coastal communities in eastern Canada to prepare for large-scale tsunami inundation by informing evacuation strategies and policy and planning decisions through scientific evidence-based public education, and identifying and preserving key natural coastal ecosystems (e.g., barrier islands and salt marshes) that serve as important barriers to tsunami inundation.

从加勒比海向北到美国和加拿大大西洋沿岸的航线容易受到飓风和海啸的海洋淹没。海啸淹没的潜在来源包括当地（波多黎各海沟）和远场地震。历史记录确定了远场事件，但没有明显的海啸起源于波多黎各海沟。目前尚不清楚外部隆起或逆冲断裂以及随后的海啸是否对西大西洋构成更大的风险。 外隆断裂预计不会在英属维尔京群岛的阿坎萨达产生任何陆地水平变化，也不会产生大地震或海啸。相反，模型表明，逆冲地震的情况将产生50厘米的同震下沉和随后的海啸，将淹没从加勒比岛屿到加拿大东部的沿海地区。为了解决这一知识差距，Jessica Pilarczyk博士（西蒙弗雷泽大学）和Davin Wallace博士（南密西西比大学）将采用现场，实验室，统计和建模技术的创新组合，以先前确定为可能源自波多黎各海沟海啸的前哥伦布时期的砂片。这些方法将用于测试波多黎各海沟沿着过去破裂的来源，并回答有关未来可能发生的地震震级和海啸强度的问题。 加强对未来地震和海啸的了解，将使加拿大东部沿海社区能够为大规模海啸淹没做好准备，方法是通过科学证据为基础的公众教育，为疏散战略和政策及规划决策提供信息，并确定和保护主要的自然沿海生态系统（例如，屏障岛屿和盐沼），这些岛屿是海啸淹没的重要屏障。