On Thursday March 18th at 8:00 PM the U.S. Geological Survey (USGS) Pasadena Office will continue their free Public Lectures series. The presentation, entitled "Earthquake Conversations" will be given by USGS scientist Dr. Ross Stein.

For decades, we dreamed of being able to divine the time and place of the world's next disastrous shock. But by the early 1980s most of us concluded that the planet's largest tremors are isolated, random and utterly unpredictable. Once a major earthquake and its aftershocks do their damage, the fault will remain quiet until stresses in the earth's crust have time to rebuild, and the earthquake will have little effect on other faults. But a new hypothesis, termed earthquake stress triggering, is beginning to overturn that assumption. Faults are seen instead to be unexpectedly responsive to subtle stresses they acquire as neighboring faults shift and shake. Although there are dissenting and competing views, stress triggering may well explain the outstanding features of seismicity, including the distribution and decay of aftershocks, the occurrence of earthquake sequences, and seismic quiescence.

All lectures are free and begin at 8 PM in Baxter Lecture Hall on the Caltech campus in Pasadena. There is plenty of free parking available.

For more information see http://pasadena.wr.usgs.gov/info/lectures/ or call 626-583-6801 or 626-583-7823.