Living on Top of Trouble
The San Francisco earthquake of 1906 is remembered as one of the greatest natural disasters in America’s history. Its consequences were terrible and devastating, yet at the same time, many lessons were learned from it.
The city of San Francisco, along with a significant part of California, lies in an earthquake-prone zone caused by the active San Andreas Fault system which runs from Cape Mendocino all the way to the Mexico/U.S. border. Seismic tremors in this area are common, but the activity in 1906 was truly tragic.
San Francisco: The Epicenter of the Quake
When it struck the epicenter of the great San Francisco earthquake was only three kilometers (two miles) away from the city in the Pacific Ocean, and its tremors were felt for a much larger distance. Tremors were reported to the north in Oregon, as far south as Los Angeles and as far east as central Nevada.
It is estimated that the magnitude of the quake was between 7.7 and 7.9 on the Richter scale, but its full intensity could not be precisely determined at the time
Just How Great Was the Quake?
Keeping in mind the historical period in which the earthquake occurred, it’s a challenge to state its real size.
It wasn’t until three decades later, in 1935, that the modern Richter scale for measuring earthquakes was developed, so the estimates of the strength of the San Francisco earthquake was made years later based on data recorded in observatories around the world.
The initial estimate was an 8.3 on the Richter scale, but the calculations were later revised.