Quake Characteristics near Canada's Coasts

影响加拿大人的地震有90%发生在加拿大海岸附近，从海岸到海岸的地震特征是至关重要的。这些eq绝大多数发生在近海，这表明海啸可能直接威胁到加拿大沿海地区的人口。由于到目前为止，加拿大缺乏宽带海底地震仪（BBOBS），因此对这些eq的了解非常有限。在接下来的5年里，我建议使用最先进的方法和由位于达尔豪斯大学的国家地震成像设施（NFSI）的新BBOBS记录的前所未有的地震数据来研究加拿大沿海地震的特征（例如，EQs和滑坡）。我将重点介绍加拿大西海岸近海的夏洛特女王断层（QCF）和加拿大东北部近海的巴芬湾西部。QCF位于太平洋和北美构造板块之间，位于加拿大西部和阿拉斯加东南部海域，具有高变形率（50 ~ 50 mm/年）。由于缺乏现代地球物理数据和先进的方法，该边缘EQ破裂过程中应变调节和脆性破坏的主要控制机制仍然未知。我将参加一项加拿大-美国的综合地震调查，计划于2020-2021年沿着QCF的约450公里段进行，该段包括板块边界倾角的系统变化。62个bbob将部署15个月。小型eq将被检测和定位使用我开发的方法。我们将开发一种最先进的震源机制反演方法来确定小eq的相对源参数。我们的eq位置和震源机制有望揭示详细的地震结构和板块边界变形机制的空间变化。巴芬湾位于高情商风险区。2017年6月17日，有史以来最高的海啸之一（100米高）摧毁了格陵兰岛西部Nuugaatsiaq的偏远定居点，该定居点与加拿大努纳武特的巴芬湾正对面。我将参加加拿大对巴芬湾西部的多学科调查。利用机器学习技术，我们将开发一个最先进的地震活动检测和分类系统，该系统将使用2020-2021年期间部署在巴芬湾西部的30个BBOBS的数据。结合规划的地质和考古工作成果，我们将为研究区域提供详细的地质灾害图，概述山体滑坡、地震和海啸的威胁。震源表征是地震学的基础，但具有挑战性，特别是震源机制反演及其分类。我提出的研究不仅进行科学观察，而且提供地质灾害预测。我预计我们的研究结果将被NRCan、DRDC和地方政府等多个组织使用，最终使许多加拿大人受益。

Ninety percent of earthquakes (EQs) that affect Canadians happen near Canada's coasts and it is crucial to characterize these EQs from coast to coast. A large majority of these EQs occur offshore, indicating potential for tsunamis that directly threaten the coastal population of Canada. Due to the lack of broadband ocean bottom seismometers (BBOBS) in Canada so far, very limited knowledge about any of these EQs has been accumulated. For the next 5 years, I propose to study the characteristics of Canada's coastal quakes (e.g., EQs and landslides) using state-of-the-art methods and unprecedented seismic data recorded by the new BBOBS from the National Facility for Seismic Imaging (NFSI) housed at Dalhousie University. I will focus on the Queen Charlotte Fault (QCF) offshore the west coast of Canada and the western Baffin Bay offshore northeastern Canada. The QCF is located between the Pacific and North American tectonic plates offshore western Canada and southeast Alaska and sustains high deformation rate (>50 mm/yr). The mechanisms of strain accommodation and primary controls on brittle failure during EQ ruptures along this margin remain unknown due to the lack of modern geophysical data and advanced methods. I will take part in a comprehensive Canada-US seismic survey scheduled for 2020-2021 along ~450 km segment of the QCF that encompasses systematic variations in plate boundary obliquity. Sixty-two BBOBS will be deployed for 15 months. Small EQs will be detected and located using methods that I have developed. We will develop a state-of-the-art focal mechanism inversion method to determine relative source parameters of small EQs. Our EQs locations and focal mechanisms are anticipated to reveal spatial variations in the detailed seismic structure and deformation mechanism of the plate boundary. Baffin Bay is situated in a zone of high EQ risk. On June 17, 2017, one of the tallest (100 m-high wave) tsunamis in recorded history devastated the remote settlement of Nuugaatsiaq in western Greenland, directly across Baffin Bay from Nunavut, Canada. I will participate in a multidisciplinary Canadian investigation of the western Baffin Bay. Using machine learning techniques, we will develop a start-of-the-art system for seismicity detection and classification using data from 30 BBOBS to be deployed in the western Baffin Bay during 2020-2021. Integrated with the results of the planned geological and archeological work, we will provide a detailed geohazard map for the study area summarizing the threat from landslides, EQs, and tsunamis. Source characterization is fundamental but challenging in seismology, which is especially true for focal mechanism inversion of quakes and their classification. My proposed research not only conducts scientific observation but also provides geohazard prediction. I anticipate that our results will be used by multiple organizations such as NRCan, DRDC and local governments, ultimately to the benefit of many Canadians.