JUDGMENT ON STRONG EARTHQUAKE RISK PROBABILITIES AND EARTHQUAKE MODES WITH SEISMICITY INDEXES
Tan Chengyc Ruan Shengna Yang Guifen (Seismological Bureau of Yunnan Province, Kunming)
The territry of Yunnan Povince and its border areas are divided into network by square degrees. We have established two single factor prediction criteria in terms of seismic data since 1965, and a multiple factor synthetic judgement procedure has been composed to decide the earthquake risk of 31 square degree regions excluded border areas in period of 1970-1986. Result shows that three earthquakes of M≥7 can be determined correctly, however, two earthquakes of 6.5≤M7.0 fail to report and there has been 9 reports of false decisions. There are 516 sample to be judged correctly in a total of 527 samples of 31 regions in 17 years.The probability of M≥6.5 earthquake of a certain area in the next year can be given on the necessary indexes by the process of making a determination in this paper.The corresponding judgements have also been established for the future strong seismicity modes by using the seismic data. And seismicity modes of M≥6.5 three earthquakes having determined in Yunnan province can be correctly predicated.