Earthquake rupture mechanisms from induced events to megathrusts

该研究项目促进了对地震过程的理解，从海啸引发的特大逆冲到诱发的地震活动，并改善了加拿大和世界范围内地震灾害的缓解和反应。从长远来看，这些知识将有助于对地震周期的基本理解。海啸性地震是一种主要的灾害，正如毁灭性事件（如印度洋、日本）所悲惨记录的那样。虽然高质量的数据越来越多，但在方法和理解上存在重大差距。虽然诱发地震与破坏无关，但人们仍然非常担心它们会造成破坏，而且人们对其控制过程和规模知之甚少。******在这里，最先进的贝叶斯反演和高性能计算结合起来解决震源研究的两个关键领域：(1)成像断层破裂的时空演变（有限断层反演，FFI）和(2)研究破裂复杂性（源-时间函数，多段破裂）与点源模型作为质心矩张量（CMT）包括高阶张量。******(1)我的研究表明，通过采用定量贝叶斯模型选择来消除对故障离散化的主观选择，可以获得更鲁棒的FFI结果。然而，断层几何形状、传感器覆盖范围和破裂复杂性对滑动分辨率的影响仍然未知。该程序将贝叶斯模型选择应用于故障的各个方面（大小，离散化，方向）和数据噪声参数，以解决这些缺点。******(2)同样，CMT反演也受到非唯一性和主观参数化选择的困扰，如固定事件深度，这往往会混淆解释。我们将通过CMT参数和质心位置的非线性不确定性量化来研究这些问题。此外，模型选择将应用于考虑多质心和高阶张量的破裂复杂性。这两个研究重点将应用于大地测量（GPS，海底GPS，高速率GPS，激光雷达），地震和海啸数据以及微地震钻孔和地面观测。******本研究可以克服目前来源研究的局限性，提供更严格、客观的结果，提高构造和地震解释的可信度。为了实现这些目标，我将加强现有的国内和国际合作，与领先的机构（澳大利亚国立大学- ANU，澳大利亚地球科学，NRCan，维多利亚大学）和行业合作伙伴（微地震行业联盟）提供高质量的HQP培训。培训工作的结构是产生可量化的研究和培训成果，其形式包括同行评议的文章、会议报告和改进地震灾害评估和早期预警的实用方法。

This research program advances understanding of earthquake processes at scales from tsunamigenic megathrusts to induced seismicity and improves seismic hazard mitigation and response in Canada and worldwide. In the long-term, this knowledge will contribute to the fundamental understanding of earthquake cycles. Tsunamigenic earthquakes are a major hazard, as tragically documented by devastating events (e.g. Indian Ocean, Japan). While high-quality data are increasingly available, significant gaps in methods and understanding exist. Although induced earthquakes are not associated with devastation, significant concerns exist that they can cause damage and little is known about the governing processes and scales. ******Here, state-of-the-art Bayesian inversion and high-performance computing are brought together to tackle two key areas of earthquake source studies: (1) Imaging the spatiotemporal evolution of rupture on faults (finite fault inversion, FFI) and (2) studying rupture complexity (source-time function, rupture of multiple segments) with point-source models as centroid moment tensors (CMT) including higher-order tensors. ******(1) My research shows that more-robust FFI results are obtained by employing quantitative Bayesian model selection to eliminate subjective choices about fault discretization. However, the effects of fault geometry, sensor coverage and rupture complexity on slip resolution are still unknown. This program will apply Bayesian model selection to all aspects of the fault (size, discretization, orientation) and to data-noise parameters to address these shortcomings. ******(2) Similarly, CMT inversion is plagued by non-uniqueness and subjective parametrization choices, such as fixing event depth, which often obfuscate interpretation. We will study these issues by non-linear uncertainty quantification of CMT parameters and centroid location. In addition, model selection will be applied to rupture complexity by considering multiple centroids and higher-order tensors. Both research focuses will be applied to geodetic (GPS, seafloor GPS, high-rate GPS, LiDAR), seismic, and tsunami data and to microseismic borehole and surface observations.******This research can overcome current limitations of source studies and provide more rigorous, objective results that enhance credibility of tectonic and seismic interpretations. To achieve these goals, I will strengthen my existing national and international collaboration with leading institutions (Australian National U. - ANU, Geoscience Australia, NRCan, UVic) and industry partners (Microseismic Industry Consortium) to provide high-quality HQP training. The training effort is structured to produce quantifiable research and training outcomes in the form of peer-reviewed articles, conference presentations, and practical methods that improve seismic hazard assessment and early warning.