The Loma Prieta earthquake occurred on October 17, 1989 at 5:04 p.m. Pacific Daylight Time. It had a moment magnitude of 6.9 and a surface wave magnitude of 7.1. The duration was 15 to 20 seconds. The earthquake occurred due to slip in either the San Andreas Fault or a subsidiary fault. The epicenter was near Loma Prieta, which is a peak in the Santa Cruz mountains. This location is 10 miles northeast of the city of Santa Cruz. A strong-motion seismograph gave an acceleration reading of 0.64 G near the source.

The Great Hanshin earthquake occurred at 5:46 a.m. on Tuesday, January 17, 1995. This earthquake is also called by the following names: Kobe, South Hyogo, Hyogo-ken Nanbu. The earthquake had a local magnitude of 7.2. The duration was about 20 seconds. The focus of the earthquake was less than 20 km below Awaji-shima, an island in the Japan Inland Sea.