Statistical Test of the Correlation Between Earthquakes and Solid Tidal Waves: Implication to Hazard Prediction

Abstract

The statistical correlation between earthquakes and the characteristics of solid Earth tide was investigated. Worldwide data on earthquakes (4018 M ≥ 6.0) from January 1, 1973 to December 31, 2003 were analyzed. The distributions (D) of three relationships among earthquakes and solid tidal forces derived by composite force FIi [D (FIi)], azimuth Ai [D (Ai)], and elevation Ei [D (Ei)] from 1,200 waves were examined. These relationships indicate the probability of earthquakes. Twelve large-amplitude waves were investigated in detail to determine if earthquakes can be predicted. A test model P(t, λ, φ, d) consisting of three different wave groups was designed using these distributions. The values of tidal force, including the size and direction of tidal waves at any given time and place, were converted to test the probability of an earthquake. The converted values were then applied to trace and ascertain the great M = 9.0 Northern Sumatra earthquake on December 26, 2004. Although the results selected from both the 12 maximum-amplitude waves or the 50 best correlation waves did not match well, the model can be significantly improved to produce only a day’s difference when all the 1,200 waves are employed. Therefore, further studies should be conducted to test if this method can be adopted in accurately predicting the occurrence of earthquakes, including time, relevant size, and location.