Subduction zone geodynamics and earthquake processes

俯冲带地球动力学和地震过程

• 批准号: RGPIN-2016-03738
• 负责人: Wang, Kelin
• 金额: $ 2.62万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=707938
• 关键词: Subduction; zone; geodynamics; earthquake; processes

This proposal seeks limited funds to provide partial support for two to three graduate students at any given year over the next five years as part of my research program. The proposed research is designed to understand the works of subduction zones, for which the Cascadia subduction zone off Canada's west coast is a near-home example. The students will study what enables megathrust faults to generate large earthquakes and what makes them creep in slow slip events, how stress is built up and relieved in earthquake cycles to affect the geology of the upper plate, whether and why seismic activities in areas very far apart are physically connected, and so forth. The proposed research addresses fundamental geodynamics, and it helps society to understand what causes seismic and tsunami hazards. Our main method is to use computer modelling to explain global multidisciplinary observations to reveal underlying physical principles. The students are directed to develop geodynamic concepts from large volumes of observations and basic principles, not merely from textbooks and conventional models. With the long-term goal of understanding the geodynamics of subduction margins, especially processes that govern earthquake generation, we will proceed in three interrelated research directions over the next five years. The first direction is to explore the link between earthquake cycle deformation and geological deformation. We need to examine subduction margins around the world and develop models with realistic, although complex, mechanical properties to investigate stress and structural evolution over individual and multiple earthquake cycles. The second direction is to study whether the decoupling of the shallow and harder part the Earth (the lithosphere) and the deeper and softer part (the asthenosphere) can explain seemingly mysterious long-range interactions of regions very far apart, either in the same subduction zone or in different subduction zones. The third direction is to address how temperature and fluids control the slip behaviour of subduction faults, in particular to develop a unified model to explain geophysical conditions for slow slip events and the relation of these events with the part of the fault that generates great earthquakes.

这项提案寻求有限的资金，在未来五年的任何一年为两到三名研究生提供部分支持，作为我研究计划的一部分。拟议的研究旨在了解俯冲带的工作，加拿大西海岸的卡斯卡迪亚俯冲带就是一个近家的例子。学生们将研究是什么使巨型逆冲断层产生大地震，是什么使它们在缓慢滑动事件中蠕动，在地震周期中应力是如何积聚和释放的，从而影响上板块的地质，相隔甚远的地区的地震活动是否以及为什么是物理连接的，等等。拟议的研究涉及基本的地球动力学，它有助于社会了解地震和海啸灾害的原因。我们的主要方法是使用计算机建模来解释全球多学科观测，以揭示潜在的物理原理。指导学生从大量的观察和基本原理中发展地球动力学概念，而不仅仅是从教科书和传统模型中。