Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Crampin, S. Articles by Peacock, S. Search for Related Content GeoRef GeoRef Citation

Stress-forecasting (not predicting) earthquakes: A paradigm shift?

¹ School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK
² Institute of Earthquake Science, China Earthquake Administration, 100036 Beijing, China
³ AWE Blacknest, Brimpton, Reading RG7 4RS, UK

Correspondence: *E-mail: scrampin{at}ed.ac.uk

After 120 years of unsuccessful endeavor, a paradigm shift is required before earthquakes can be predicted. The most sensitive diagnostic of low-level changes of stress in in situ rock, variations in microcrack geometry, can be monitored by analyzing shear-wave splitting. The suggested paradigm shift is that, instead of investigating the source zone, we monitor stress accumulation before earthquakes at, possibly, substantial distances from the source. Characteristic temporal variations of shear-wave time delays have been observed in retrospect before 14 earthquakes worldwide. On one occasion, when changes were recognized early enough, the time, magnitude, and fault break of an M = 5 earthquake in southwest Iceland were successfully stress-forecast in a narrow time-magnitude window. Such stress accumulation can be theoretically modeled and is believed to be at least partially understood. When sufficient shear-wave source earthquakes are available, increasing time delays also show an abrupt decrease shortly before the impending earthquake occurs. This is not fully understood but is thought to be caused by stress relaxation as microcracks coalesce onto the eventual fault break. The new result confirming these ideas, and justifying the paradigm shift, is that logarithms of the durations of both increases and decreases in time delays are found to be proportional (self-similar) to the magnitudes of impending earthquakes.

Key Words: stress accumulation • paradigm shift • shear-wave splitting • stress-forecasting earthquakes

This article has been cited by other articles:

				C. Chiarabba, P. De Gori, and E. Boschi Pore-pressure migration along a normal-fault system resolved by time-repeated seismic tomography Geology, January 1, 2009; 37(1): 67 - 70. [Abstract] [Full Text] [PDF]