A Simulation Approach for Better Understanding of Seismic Hazard and Risk in Montreal

Yelena Kropivnitskaya, Kristy F. Tiampo, Jinhui Qin, & Michael Bauer

Published August 12, 2016, SCEC Contribution #6628, 2016 SCEC Annual Meeting Poster #196

Despite the fact that seismic activity occurs primarily along plate boundaries, large earthquakes also occur within the plates and result in significant human and economic losses (Adams and Basham, 1989). Unlike seismicity along the plate boundaries, intraplate seismicity is unevenly distributed and often poorly understood. For example, the Charlevoix seismic zone, the most seismically active region in eastern Canada is located in a stable continental region within the North American Plate. While it has a relatively low rate of earthquake activity, this largely urban region has experienced six earthquakes of approximately magnitude 6 since 1663, with large earthquakes concentrated in regions of crustal weakness (GSC, 2016). Sykes (1978) found that, in general, most events within northeastern America occur in those areas affected by the last major orogenesis, before the opening of the Atlantic Ocean. Eastern Canadian seismicity may be the result of reactivation of existing fault zones and other tectonic boundaries, such as in the late Proterozoic to Paleozoic fault system along the St. Lawrence and Ottawa rivers (Thomas, 2006).
Montreal, located in the seismically active region of the western Quebec seismic zone, is one the largest and most populated cities in the eastern Canada. Here we present the steps and results of a high-performance computing application to probabilistic seismic hazard analysis (PSHA) for Montreal. The simulations are performed based on the pipelining implementation of the EqHaz program suite (Assatourians & Atkinson, 2013) in the IBM InfoSphere Streams (Kropivnitskaya et al., 2015). This pipelined hazard mapping approach identified two main processing operators as bottlenecks: the catalog generation operator using Monte Carlo simulations and the map generation operator. The workload of the hazard mapping workflow has been decomposed and these two operators have been split into multiple pipelines for parallel execution. This allows for the computation of hazard maps for different frequency bands at significantly increased resolution with much lower latency time for Montreal city. Moreover, a range of high-resolution sensitivity tests are performed and conclude with insights as to which input factors and parameters significantly affect the ground motion results and are the main sources of uncertainty. In addition, the potential application of streaming techniques (Kropivnitskaya et al., 2015) to near-real time high-resolution shakemap production for scenario or actual events is demonstrated here. These results can be used by policymakers to set earthquake resistant construction standards, by insurance companies to set insurance rates and by civil engineers to estimate stability and damage potential for Montreal city.

Citation
Kropivnitskaya, Y., Tiampo, K. F., Qin, J., & Bauer, M. (2016, 08). A Simulation Approach for Better Understanding of Seismic Hazard and Risk in Montreal. Poster Presentation at 2016 SCEC Annual Meeting.

Related Projects & Working Groups
Seismology