What magnitude earthquake is associated with the San Fernando Valley?

The magnitude of the earthquake that is most commonly associated with the San Fernando Valley is 6.6. However, the San Fernando earthquake, which occurred in 1971, is often reported as having a magnitude of 6.6 or 6.7 depending on the source. This earthquake caused significant damage and is an important event in the study of seismic activity in the Los Angeles area.

While the choice of 5.6 may seem plausible, it does not accurately reflect the recognized magnitude of this significant seismic event. Earthquakes can vary greatly in their impact and are measured on a logarithmic scale, where each whole number increase corresponds to a tenfold increase in amplitude. Therefore, knowing the correct magnitude of significant historical earthquakes, such as the one in San Fernando Valley, is essential for understanding the region's geological hazards and preparing for future seismic events.