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arXiv · 1203.1031

Are megaquakes clustered?

Eric G. Daub·Eli Ben-Naim·Robert A. Guyer·Paul A. Johnson
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Abstract

We study statistical properties of the number of large earthquakes over the past century. We analyze the cumulative distribution of the number of earthquakes with magnitude larger than threshold M in time interval T, and quantify the statistical significance of these results by simulating a large number of synthetic random catalogs. We find that in general, the earthquake record cannot be distinguished from a process that is random in time. This conclusion holds whether aftershocks are removed or not, except at magnitudes below M = 7.3. At long time intervals (T = 2-5 years), we find that statistically significant clustering is present in the catalog for lower magnitude thresholds (M = 7-7.2). However, this clustering is due to a large number of earthquakes on record in the early part of the 20th century, when magnitudes are less certain.

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BibTeXRIS

Eric G. Daub, Eli Ben-Naim, Robert A. Guyer, Paul A. Johnson. 2012-03-05. Are megaquakes clustered?. https://doi.org/10.1029/2012gl051465

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