Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

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.