NPG Nonlinear Processes in Geophysics NPG Nonlin. Processes Geophys. 1607-7946 Copernicus Publications Göttingen, Germany 10.5194/npg-17-513-2010 Intraplate seismicity in Canada: a graph theoretic approach to data analysis and interpretation Vasudevan K. 1 Eaton D. W. 1 Davidsen J. 2 Department of Geoscience, University of Calgary, Calgary, Alberta T2N 1N4, Canada Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4, Canada 04 10 2010 17 5 513 527 Copyright: © 2010 K. Vasudevan et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://npg.copernicus.org/articles/17/513/2010/npg-17-513-2010.html The full text article is available as a PDF file from https://npg.copernicus.org/articles/17/513/2010/npg-17-513-2010.pdf

Intraplate seismicity occurs in central and northern Canada, but the underlying origin and dynamics remain poorly understood. Here, we apply a graph theoretic approach to characterize the statistical structure of spatiotemporal clustering exhibited by intraplate seismicity, a direct consequence of the underlying nonlinear dynamics. Using a recently proposed definition of "recurrences" based on record breaking processes (Davidsen et al., 2006, 2008), we have constructed directed graphs using catalogue data for three selected regions (Region 1: 45°−48° N/74°−80° W; Region 2: 51°−55° N/77°−83° W; and Region 3: 56°−70° N/65°−95° W), with attributes drawn from the location, origin time and the magnitude of the events. Based on comparisons with a null model derived from Poisson distribution or Monte Carlo shuffling of the catalogue data, our results provide strong evidence in support of spatiotemporal correlations of seismicity in all three regions considered. Similar evidence for spatiotemporal clustering has been documented using seismicity catalogues for southern California, suggesting possible similarities in underlying earthquake dynamics of both regions despite huge differences in the variability of seismic activity.

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