Characteristic earthquake model, 1884 -- 2011, R.I.P.

Yan Y. Kagan, David D. Jackson, & Robert J. Geller

Published 2012, SCEC Contribution #1671

Unfortunately, working scientists sometimes reflexively continue to use buzz phrases grounded in once prevalent paradigms that have been subsequently refuted. This can impede both earthquake research and hazard mitigation. Well-worn seismological buzz phrases include "earthquake cycle," "seismic cycle," "seismic gap," and "characteristic earthquake." They all assume that there are sequences of earthquakes that are nearly identical except for the times of their occurrence. If so, the complex process of earthquake occurrence could be reduced to a description of one "characteristic" earthquake plus the times of the others in the sequence. A common additional assumption is that characteristic earthquakes dominate the displacement on fault or plate boundary "segments." The "seismic gap" (or the effectively equivalent "seismic cycle") model depends entirely on the "characteristic" assumption, with the added assumption that characteristic earthquakes are quasi-periodic. However, since the 1990s numerous statistical tests have failed to support characteristic earthquake and seismic gap models, and the 2004 Sumatra earthquake and 2011 Tohoku earthquake both ripped through several supposed segment boundaries. Earthquake scientists should scrap ideas that have been rejected by objective testing or are too vague to be testable.

Kagan, Y. Y., Jackson, D. D., & Geller, R. J. (2012). Characteristic earthquake model, 1884 -- 2011, R.I.P.. Seismological Research Letters, 83(6), 951-953. doi: 10.1785/0220120107.