Hi 2 cents. I hope Lowell doesn’t mind too much my using his and Ben-Zion’s material.

What you’re referring to sounds a little like free oscillations. An earthquake prediction scheme was briefly presented by Whiteside and Ben-Zion (1995).

“They orally reported results suggesting that free oscillations of the earth were able to trigger earthquakes and that this triggering occurred preferentially in time and space prior to impending earthquakes. The underlying physical idea was that in the hypocentral region of an impending earthquake the stress was close enough to the failure strength of the rock, or the frictional strength of minor faults. Their suggestion was that the stresses involved in normal mode vibrations of the earth are high enough to trigger microseismicity, perhaps only by advancing their time of occurrence by a few minutes. Thus the proposed method can be thought of as a way of distinguishing foreshocks from normal background microseismicity by their sensitivity to triggering. Although the idea has some appeal, the magnitudes of free oscillation stresses are much smaller than tidal stresses; since tides apparently seldom trigger earthquakes, the likelihood that free oscillations could trigger earthquakes seems low.”

“However, the data presented by Whiteside and Ben-Zion (1995) suggested that before several major earthquakes, notably the Loma Prieta earthquake of 1989, there was a significant increase in free-oscillation-triggered earthquakes in the epicentral area. Thus although the physical plausibility of the method seemed low, the suggestive results presented warranted an independent study of the situation.”

Costello, S. W., and T. E. Tullis conducted the research to see if the same thing could occur by random chance. According to there study what Dr. Lowell Whiteside and Dr. Ben-Zone presented was no better then random chance.

I decided to do a little research on my own using the NEIC catalog which by the way isn’t what you would call the best catalog to be using for this study.

Using only quakes with a magnitude M>4.0 and greater I found that there were 16 quakes from 1865 to 1968 with two of them with a magnitude of M>5.0+. From 1968 to April of 1981 there were no quakes above M>4.0. From April 1981 there were 7 quakes above M>4.0 with two of them with a magnitude of M>5.0+ to 10/18/1989, the date of Loma Prieta quake. Now maybe to over all number of quakes to occur was no better then random chance, but to have 7 quakes above M>4.0 in a seven year period I feel is more then just random chance.

By the way the Loma Prieta quake was forecasted using the very same data I was using to make my forecasts. Think about it. Take Care…Don in creepy town

• Free Oscillations/Earthquake Prediction