A NOTE ON A RELATION BETWEEN THE SYNTHETIC AND INDIVIDUAL PROBABILITIES IN THE QUANTITATIVE EARTHQUAKE PREDICTION

In the earthquake prediction problem the estimation of the occurrence probability of major earthquakes by using multiple precursory data is desirable. A relation between the synthetic probability and individual probabilities for the earthquake prediction relying on a Markov chain model is discussed. A historical earthquake sequence in northern China of about two thousands years and the results from the observation of the radon content anomaly which covered a period of about ten years are used. The following linear relation is assumed: P7(D)* = alphaP3(D)(M)*.P3(D)(R)*, where alpha shows a coupling constant, a factor concerning degree of dependence of two precursory phenomena, P7(D)*, P3(D)(M)*, P3(D)(R)* are the probabilities of the earthquake occurrence normalized by the interval of the time segment in a Markov chain, when both precursors, moderate-size earthquakes, a radon content anomaly appear as precursory phenomena, respectively. Analysis shows that this relation fits well to the actual data. The value of alpha is found to be about 150-170, independent of the interval of the time segment and radon content anomaly recurrence interval.