Collaborative Research: Finite Element Modeling Of A Subducted Topographic High: Determining Regional Stress Changes Due To Subducing Features

合作研究：俯冲地形高地的有限元建模：确定俯冲特征引起的区域应力变化

• 批准号: 0440243
• 负责人: Susan Bilek
• 金额: $ 13.22万
• 依托单位: New Mexico Institute of Mining and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0440243&HistoricalAwards=false
• 关键词: Collaborative; Research; Finite; Element; Modeling

Proposal "Collaborative Research: Finite Element Modeling Of A Subducted Topographic High: Determining Regional Stress Changes Due To Subducing Features" EAR 0440243 and 0440229 With the majority of global seismicity occurring in subduction zones, it is very important to understand the stress conditions in the subduction environment. Variations in the details of earthquakes in these regions are likely due to variations in stress conditions between subduction zones. Key factors that can impact the stress conditions in subduction zones include mantle flow and the interaction between the overriding and subducting plates at the plate interface. The plate interface may vary in roughness depending on a variety of features on the incoming plate, such as presence of thick sediment packets, horst and graben structures, seamounts, ridges, and fracture zones. These subducting plate structures not only influence the stress state within the subduction zone, but may also control the size and rupture behavior of large subduction zone earthquakes, as suggested for large earthquakes in Costa Rica and Nankai subduction zones. This proposal focuses on examining the stress state in these two subduction zones, with goals to examine the relationship between stresses, subducted features, and seismicity patterns seen in Costa Rica and Nankai, stress triggering of large earthquakes in these regions, and determining conditions for which topographic features may act as zones of high earthquake slip or a barrier to earthquake rupture. Two and 3D modeling of the subduction zone environment will provide opportunities to explore the effects of viscoelastic relaxation and triggering, frictional properties at the trench interface, and the bathymetric variability of the subducted oceanic lithosphere on earthquake patterns. Results from this effort will be applied to knowledge of earthquake hazards in Costa Rica and Nankai, and may be extended to other subduction zones as well.

提案”协作研究：俯冲地形高俯冲地形的有限元模型：确定由于特征的特征而引起的区域应力变化“ EAR 0440243和0440229，大部分全球地震性发生在俯冲Zones中，这对于理解脱落环境中的压力条件非常重要。这些区域地震细节的变化可能是由于俯冲带之间的应力条件变化所致。可能影响俯冲带应力条件的关键因素包括地幔流以及板界面处的压倒板和俯冲板之间的相互作用。板界面的粗糙度可能会因传入板上的各种特征而变化，例如存在厚厚的沉积物包，Horst和Graben结构，船舱，山脊和断裂区域。这些俯冲板结构不仅影响俯冲带内的应力状态，而且还可能控制大俯冲带地震的大小和破裂行为，这是哥斯达黎加和南卡俯冲带的大地震的建议。该提案的重点是检查这两个俯冲区中的应力状态，其目标是检查压力，俯冲特征和地震性模式之间的关系，在哥斯达黎加和南卡伊（Nankai）中看到的地震性模式，在这些地区触发大型地震的压力以及确定地形特征的条件可以作为地球上的地形或地球上的地形区域，成为地球上的地震或壁架上的地震区域。俯冲带环境的两种和3D建模将为探索粘弹性松弛和触发的影响，沟槽界面处的摩擦特性以及俯冲岩层岩石圈对地震模式的测深变异性。这项工作的结果将应用于哥斯达黎加和南卡伊的地震危害的知识，也可以扩展到其他俯冲带。