April 18, 1906, was the day that San Francisco shook. The Great San Francisco Earthquake blasted the city awake, and that, plus aftershocks and a terrible series of fires, managed to destroy the city. Try answering these trivia questions about a seismic event that demands respect.
Why Were the Fires Following the Quake So Devastating? Those fires were bad for a number of reasons. After the quake, which damaged a lot of buildings but still left many standing, and a subsequent large aftershock that took down more buildings, the city had to deal with fires starting due to broken gas lines. However, the quake took out the city's water main system, meaning firefighters had nothing to fight with. Add to that the wooden construction of many of the buildings, and you have a perfect storm of fire and fuel with no way to stop the flames. Three days after the first quake, a rainstorm blew in and put out the fires. But the situation had been so desperate that it's not hard to imagine the fires continuing to burn unchecked if that rain hadn't come in.
What Geologic Effects Did the Quake Have? This was a huge quake, officially measuring 8.3 on the Richter scale, though its magnitude has also been given as 7.8 and 7.9. In fact, it was so huge that it was felt from Oregon around to Nevada and down to Southern California (cities in central California experienced heavy quake damage, too), and attempts to assign a Modified Mercalli Intensity value to the quake were difficult, with some areas apparently qualifying for an MMI value (in Roman numerals) of X. The quake was powerful enough to be recorded thousands of miles away in Cape Town, South Africa, and its effect on San Francisco was cataclysmic.
What Technological First Did the Quake Necessitate? The quake was the first major disaster in which communication centers had used wireless telegraphy. One of the ships that helped save survivors of the quake from fire was the USS Chicago, which had been based at San Diego. The ship received telegraphic reports of the quake from one of the telegraph stations in San Diego, at which point the admiral in charge of the ship ordered the engines started. The mayor of San Diego agreed that the ship should head to San Francisco (it arrived on the 19th).
How Did the Quake Help the Bay Area Grow?
The city was essentially destroyed by the quake and subsequent three-day
fire; the quake also caused landslides and demolished forests. While
that was, at the time, a tremendous tragedy, it gave city planners the
opportunity to undertake an immense urban renewal project. San Francisco
had originally been built without much of a plan, instead growing
organically as more people arrived after the Gold Rush. But with the
city flattened by the quake and fire, planners were able to rebuild the
entire city according to a more logical layout plan. Another effect was
that, as survivors moved out of San Francisco in search of housing, they
contributed to population growth in the surrounding cities.