Assessing Earthquake Hazards in the Cascadia and Chilean Subduction Zones

拟议研究计划的目标是利用各种新数据集结合改进的地球成像方法，改进我们对卡斯卡迪亚和智利俯冲带地震危险性的评估。具体来说，我们将使用新的密集地震阵列数据绘制智利和卡斯卡迪亚俯冲带的部分地图。各种地球建模技术将被利用，包括地震层析成像和接收函数分析。这些将与最近改进的贝叶斯反演方法相结合。我们将使用智利最近发生的四次大俯冲地震的记录，分别是2010年（Mw 8.8） Maule地震、2014年（Mw 8.2） Iquique地震、2015年（Mw 8.3） Illapel地震和2016年（Mw 7.6） Quell’on地震。研究沿智利边缘的俯冲板块年龄和俯冲方式对地面震动的影响，并将观测到的震动水平（根据当地场地影响进行了修正）与智利和加拿大国家建筑规范中使用的震动水平进行比较。我们研究的后期阶段将集中于利用智利的观测资料预测卡斯卡迪亚俯冲地震的余震，那里发生的事件更多（观测将包括余震统计、震源位置、断层机制和破裂区域）。我们研究的最终目标是帮助减少加拿大和智利未来地震的影响。我们研究的预期结果和收益包括更安全的社区、更强大的基础设施、改进的决策信息，以及减少未来可能发生的地震造成的损失。

The objective of the proposed research program is to improve our assessments of earthquake hazards in both the Cascadia and Chilean subduction zones using a variety of new datasets combined with improved earth-imaging methodologies. Specifically, we will map select portions of the subduction zones in both Chile and Cascadia using data from new, dense seismic arrays. A variety of earth modelling techniques will be utilised, including seismic tomography and receiver function analysis. These will be integrated with recently improved Bayesian inversion methodologies. We will use recordings of four recent large subduction earthquakes in Chile, the 2010 (Mw 8.8) Maule earthquake, the 2014 (Mw 8.2) Iquique earthquake, the 2015 (Mw*8.3) Illapel earthquake, and the 2016 (Mw 7.6) Quell´on earthquake, to examine variations in ground shaking with age of the subducting plate and style of subduction along the Chilean margin and will compare observed shaking levels (corrected for local site effects) with those used in national building codes in both Chile and Canada. Later stages of our research will focus on forecasting aftershocks from subduction earthquakes in Cascadia using observations from Chile where many more events occur (observations will include aftershock statistics, hypocentral locations, and faulting mechanisms and rupture area). The ultimate objective of our research is to help minimise the impact of future earthquakes in Canada and Chile. The anticipated outcomes and benefits of our research includes safer communities, more robust infrastructure, improved information for decision-making, and reduced losses from earthquakes that will occur in the future.