Based on earthquake data from January 1, 1990 through December 31, 2000, Rundle, Tiampo and colleagues forecast the likely location of large magnitude quakes occurring between the years 2000 and 2010.

Their forecast was first announced at the Arthur M. Sackler Colloquium of the National Academy of Sciences held March 23-24, 2001, and is published in the February 19 supplement to Proceedings of the National Academy of Sciences (PNAS). Authors are J. B. Rundle, K. F. Tiampo, W. Klein and J. S. Sa´ Martins.

The next decade will be a real-time experiment, testing the validity of their forecasting technique. So far, three significant quakes have hit either on, or within the margin of error (11 km) near forecast locations, including last Friday's 5.7 magnitude quake and two 5.1 magnitude quakes that hit Big Bear, California on February 10, 2001, and Anza, California on October 31, 2001.

Previous attempts at forecasting large quakes based on factors such as rainfall or changes in the frequency of smaller quakes have met with limited success.

This promising new technique focuses on the spatial distribution of past earthquakes, and is similar to techniques used to forecast El Niño. The technique might also hold promise in forecasting other events such as stock market crashes or sudden extinctions in ecological systems.

In the authors' words, "Threshold systems are known to be some of the most important nonlinear self-organizing systems in nature, including networks of earthquake faults, neural networks, superconductors and semiconductors, and the World Wide Web, as well as political, social, and ecological systems.

"All of these systems have dynamics that are strongly correlated in space and time, and all typically display a multiplicity of spatial and temporal scales.

"In recent years, earthquakes and frictional sliding have emerged as the paradigm of self-organizing driven threshold systems."

[Contact: John B. Rundle, Bridget Coughlin]

27-Feb-2002