History of San Francisco world center of the computer industry. San Jose has continued since then to grow in population since it is surrounded by large tracts of developable land. Thus, San Francisco is now the second largest city in population in the San Francisco Bay Area after San Jose. On October 17, 1989, an earthquake measuring 6.9 on the moment magnitude scale struck on the San Andreas Fault near Loma Prieta Peak in the Santa Cruz mountains, approximately 70 miles (113 km) south of San Francisco, a few minutes before Game 3 of the 1989 World Series was scheduled to begin at Candlestick
1989 Loma Prieta earthquake about from the epicenter. From October 5, they reported that a substantial increase in noise was measured in the frequency range 0.01–10 Hz. The measurement instrument was a single-axis search-coil magnetometer that was being used for low frequency research. Precursor increases of noise apparently started a few days before the earthquake, with noise in the range 0.01–0.5 Hz rising to exceptionally high levels about three hours before the earthquake. Though this pattern gave scientists new ideas for research into potential precursors to earthquakes, and the Fraser-Smith et al. report remains one of the most frequently cited examples of a specific