Unravelling the complex tectonics of western and northwestern Canada using broadband seismic data

我的研究计划的目标集中在与固体地球的演化和动力学有关的悬而未决的问题上，特别是与构造活动区相关的地壳和上地幔。我通过应用和开发详细的、利用宽带地震仪器网络获得的陆上和近海三维地震速度模型来实现这些目标。先进的处理和成像工具由内部开发，并与密切合作伙伴合作，能够从现有的地震数据集中提取最大的构造信息，提供可靠的、统计上合理的分析和解释。具体地说，我的研究重点是加拿大西部和北部的活跃变形地区，通过地震速度和相关物理性质的透镜揭示的，以及地震活动的位置和模式。最终，这些目标将改善我们对地震和相关危险的评估，从而改善缓解程序，并促进整个加拿大西部和北部的深层矿物系统知识。在加拿大西部，北美大陆与复杂的近海构造系统并列在一起。这包括南部的卡斯卡迪亚俯冲带，胡安德富卡和戈尔达板块正俯冲到边缘以下。在北部，跨地压的夏洛特女王断层系统从海达瓜伊州南部向北延伸到阿拉斯加。在这两个板块边界系统之间是夏洛特女王三重交界处，这是一个由小板块和板块碎片组成的复杂区域，适应了这种变形风格的变化。这片位于不列颠哥伦比亚省海岸的广阔地区是加拿大地震风险最高的地区，在大地震(有时是巨型地震)中可能会滑落。加拿大科迪勒拉北部(NCC)和加拿大北极西南部的构造活动已有约250迈尔，拥有大量矿产和地热能源资源，以及对北部居民至关重要的交通和能源走廊。该地区也是重大地震活动的发源地，广泛分布在NCC，并从麦肯齐三角洲向北延伸到波弗特海。由于气候持续变暖，这一北部地区特别容易发生大规模浪费事件，并因永久冻土融化而发生海岸侵蚀，使其更容易受到当地和地区性地震的地面震动的影响。在拟议的研究中，我计划使用加拿大西部和北部所有可用的地震数据来约束这些复杂的构造系统，包括我与同事一起部署的西部北极地区地震仪网络(WARNS)。我的长期愿景包括未来在几个关键地区的离岸部署，包括波弗特海和夏洛特女王三重交界处，这不仅将高度补充这项工作，而且将利用加拿大地球科学界的重要机会。

The objectives of my research program focus on outstanding questions relating to the evolution and dynamics of the solid Earth, in particular the crust and upper mantle associated with tectonically active regions. I approach these objectives through the application and development of detailed, 3D seismic velocity models of the onshore and offshore obtained using networks of broadband seismic instruments. The sophisticated processing and imaging tools, developed in house and with close collaborators, enable the extraction of maximum structural information from available seismic datasets, providing robust, statistically sound analysis and interpretation. Specifically, my research focuses on the actively deforming regions of western and northern Canada, as revealed through the lens of seismic velocity and associated physical properties, as well as the location and patterns of seismicity. Ultimately, these objectives will improve our assessment of earthquake and related hazards, and therefore mitigation procedures, as well as advancing deep mineral system knowledge across western and northern Canada. In western Canada, the North American continent is juxtaposed against a complex offshore tectonic system. This includes the Cascadia Subduction Zone in the south, where the Juan de Fuca and Gorda Plates are subducting beneath the margin. In the north, the transpressional Queen Charlotte Fault system extends from southern Haida Gwaii northwards to Alaska. In between these two plate boundary systems lies the Queen Charlotte Triple Junction, a complex area of small plates and plate fragments that accommodate this change in deformation style. This broad region on the BC coast is home to the highest seismic hazard in Canada and can slip in large (and sometimes giant) earthquakes. The Northern Canadian Cordillera (NCC) and southwest Canadian Arctic has been tectonically active for ~250 Myr and is host to numerous mineral and geothermal energy resources, as well as transportation and energy corridors vital to northern residents. This region is also home to significant seismicity, distributed broadly across the NCC and extending northwards off the Mackenzie Delta into the Beaufort Sea. As a result of continued climate warming, this northern region is particularly prone to mass wasting events and coastal erosion as a result of melting permafrost, making it more susceptible to ground shaking from local and regional earthquakes. In the proposed research, I plan to use all available seismic data within western and northern Canada to constrain these complex tectonic systems, including the Western Arctic Regional Network of Seismographs (WARNS), a network I deployed with colleagues. My long-term vision includes future off-shore deployments in several key areas, including the Beaufort Sea and Queen Charlotte Triple Junction, which will not only be highly complementary to this work, but capitalize on important opportunities for the Canadian geoscience community.