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

Research Article| May 01, 2008 Stress-forecasting (not predicting) earthquakes: A paradigm shift? Stuart Crampin; Stuart Crampin * 1School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK *E-mail: scrampin@ed.ac.uk Search for other works by this author on: GSW Google Scholar Yuan Gao; Yuan Gao 2Institute of Earthquake Science, China Earthquake Administration, 100036 Beijing, China Search for other works by this author on: GSW Google Scholar Sheila Peacock Sheila Peacock 3AWE Blacknest, Brimpton, Reading RG7 4RS, UK Search for other works by this author on: GSW Google Scholar Author and Article Information Stuart Crampin * 1School of GeoSciences, University of Edinburgh, Edinburgh EH9 3JW, UK Yuan Gao 2Institute of Earthquake Science, China Earthquake Administration, 100036 Beijing, China Sheila Peacock 3AWE Blacknest, Brimpton, Reading RG7 4RS, UK *E-mail: scrampin@ed.ac.uk Publisher: Geological Society of America Received: 26 Nov 2007 Revision Received: 30 Jan 2008 Accepted: 06 Feb 2008 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2008 Geological Society of America Geology (2008) 36 (5): 427–430. https://doi.org/10.1130/G24643A.1 Article history Received: 26 Nov 2007 Revision Received: 30 Jan 2008 Accepted: 06 Feb 2008 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Stuart Crampin, Yuan Gao, Sheila Peacock; Stress-forecasting (not predicting) earthquakes: A paradigm shift?. Geology 2008;; 36 (5): 427–430. doi: https://doi.org/10.1130/G24643A.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract 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. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.