pure and applied geophysics

, Volume 145, Issue 3, pp 701–715

A new approach to earthquake prediction: The Load/Unload Response Ratio (LURR) theory


  • Xiang-Chu Yin
    • Center for Analysis and PredictionSSB
    • Institute of GeophysicsSSB
  • Xue-zhong Chen
    • Institute of GeophysicsSSB
  • Zhi-ping Song
    • Institute of GeophysicsSSB
  • Can Yin
    • China Disaster Reduction Press

DOI: 10.1007/BF00879596

Cite this article as:
Yin, X., Chen, X., Song, Z. et al. PAGEOPH (1995) 145: 701. doi:10.1007/BF00879596


The response to loading is different from that to unloading when the focal media is approaching instability. The ratio of the response rate during loading to that during unloading, called Load/Unload Response RatioY (LURR), could be a measure of the closeness degree to instability and is used in a new approach to earthquake prediction. Retrospective examination of some one hundred earthquake cases (fromM 4 toM 8.6) indicates that for more than 80% of the examined ones, the value ofY is much higher than 1 for a period before the main shock, but theY value always fluctuates slightly about 1 during two decades for seven stable regions, so that the parameterY value always fluctuates slightly degree of an impending earthquake. Several earthquakes occurring on the Chinese mainland in recent years as well as the Northridge California, U.S.A. earthquake (Jan. 17, 1994,Mw 6.7) have been predicted beforehand with this method.

Key words

Load/unload response ratioearthquake predictioninstability of nonlinear systemsNorthridge earthquake

Copyright information

© Birkhäuser Verlag 1995