Table 3: Seismic events contained in the database.

EarthquakeMagnitude PGA* (g)Epicentral distance (km)Number of patterns

1906 San Francisco7.90.28–0.2613–274
1964 Alaska9.20.21–0.3935–1007
1964 Niigata, Japan7.50.1921299
1971 San Fernando6.40.55128
1979 Imperial Valley6.5–6.60.21–0.512–632
1983 Nihonkai-Chubu, Japan7.70.252772
1987 Superstition Hills6.60.21236