Earth tides as a triggering mechanism for earthquakes

Since earth tides represent the largest short-period oscillatory strains in the earth, a test has been made to see if any correlation exists between the times of occurrence of earthquakes in Southern California and the tidal potential. Two tests have been made, one of them a cross-correlation. On either basis, a statistically significant sample of earthquake events gives a correlation with the tidal potential that is of the same magnitude as a random sample.