All textbooks on seismology begin with a description of the earthquake in San Francisco (California, USA). When the United States took it away from Mexico in 1846, it was a small village with only about six hundred inhabitants. But in 1848 gold was found in its vicinity, and this circumstance led to the rapid growth of the village. By 1906, more than four hundred thousand people lived here, and its surroundings were quite densely populated. The city, located at the Golden Gate Strait, by this time was the largest commercial port on the entire Pacific coast of America. It had many factories and factories; up to a thousand merchant ships left its port every day.
Architecturally, San Francisco was a mixture of old and new buildings. Many of them were erected without any consideration of possible natural disasters, and in fact next to it is the San Andreas Fault - a giant scar that stretches across diverse natural areas. Actually, San Francisco is located right on it. The fault has been living for 150 million years, and during this time, the movements of its various sections occurred in jerks and were accompanied by small earthquakes. The accumulating underground energy was released, and those areas of the fault where calm remains for a long time have to be feared.
Since its founding, San Francisco has experienced many earthquakes, some of which also saw minor damage. But none of the residents of the city thought about the serious danger. So in the early morning of April 18, 1906, nothing foreshadowed trouble. On the eve of the earthquake, the weather in San Francisco was fine. The warm evening attracted masses of people to theaters and parks. Restaurants and cafes were full of visitors even after midnight. The rising sun was hidden behind a light haze on the sea that covered the horizon. Meteorologists predicted clear, calm weather, and the day promised to be cool.
But suddenly the singing of birds, which had just begun, suddenly ceased, everything in nature seemed to be numb for a few moments. Frozen in suspense? But why? There were no predictions on this score. True, on the eve, on the coast of the Pacific Ocean, weak vibrations of the soil were felt, but the city could barely hear an indistinct rumble, resembling a distant cannonade. Such a phenomenon has long become commonplace, and few people paid attention to it. Residents of San Francisco have long ceased to fear such hesitation, they were not afraid this time either. In fact, they knew for a long time that they were living in an earthquake-prone zone, that tremors were inevitable, you should only take cover in time (if the tremors catch you on the street) or, in extreme cases, stay in houses and stand in the door - the safest place if it starts to collapse ceiling. “A common shaking,” said one of the townspeople."She's not half as bad as a tornado or hurricane."
At 5:11 am local time, the first blow was heard, which woke up many residents of the city, followed by the second - the most powerful and destructive, followed by a series of weaker tremors. The waves caused by these shocks in the thickness of the earth were so strong that they were noted by seismographs in the observatories of Washington, Tokyo, Birmingham, Berlin, Vienna Turin, Strasbourg, Rome, Moscow and other cities.
A terrible rumble and crackle of bursting buildings, like a crushing tornado, rolled through the streets. The underground impact, which lasted only forty seconds, shook multi-storey buildings, uplifted lanes, cut power lines, burst water and gas pipes … Asphalt collapsed, boulders flew out of the pavement, tram rails were torn apart, cars and cars overturned. A giant cloud of dust shot up into the sky and eclipsed the sun. Suddenly, darkness enveloped the whole city, and only the bright glow of conflagrations flared up in a terrible and alarming manner. A handsome city located in a cozy green bay, the resort city of San Francisco in a matter of seconds turned into flaming ruins.
The earthquake had a magnitude of 8.3 points. It lasted only forty seconds, but this time was enough to turn the flourishing city into a heap of ruins. Later, scientists found that an underground shock wave propagated from the epicenter at a speed of thirty thousand kilometers in us. Hardly anyone would have been able to escape such a shock wave if it had swept entirely under San Francisco.
But the aftershocks were enough. In an instant, factory pipes fell, the walls of houses collapsed, churches collapsed, and deep cracks appeared in the streets. Some houses simply went underground.
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The famous singer, tenor Enrico Caruso, who sang Jose's aria in Bizet's opera "Carmen", miraculously managed to escape from this earthquake. They applauded him, they did not want to let go of the famous singer, they asked to stay. He agreed to spend the night at a hotel and stayed in San Francisco. Fortunately, the hotel in which he stayed was slightly damaged and Caruso survived, although he suffered a severe nervous shock. True, from that moment on, he vowed that he would never again perform in this damn shaking city.
Four hours after the aftershocks, when the initial horror somehow subsided and the rescue teams began to dismantle the rubble, trying to remove the dead and still living citizens from under them, the first fire began in downtown San Francisco.
Actually, putting out a fire in the absence of water is the most hopeless occupation. Where to get it if the water supply lines burst? How to get to the rubble if the streets have become impassable? In 1906, there was no special fire fighting equipment, there were no necessary high-rise stairs, there were not enough fire engines. Only fire escapes remained, by which, as it was assumed, people could leave the premises enveloped in flames. Alas, these ladders were damaged by an earthquake.
For three days and three nights fire raged in the destroyed, defeated city. The rampage of fire was difficult to resist as water mains and pumping stations were damaged by tremors. Firefighters, in order to cut off the parts of the city engulfed in raging flames from the survivors, dug trenches and pulled away debris. They used explosives, and this often led to new fires. On the evening of the first day after the disaster, an excessively large charge of dynamite was used, and as a result, burning debris, scattered in different directions, fell on Chinatown, which was completely burnt out.
According to later estimates, the earthquake claimed the lives of almost a thousand people. Thirteen square kilometers of the central part of the city were destroyed by fire, and in general, five hundred blocks of the city were destroyed in the fire. More than a third of the residents, 250 thousand people, were left homeless, many of them lost not only their homes, but also their jobs. However, it turned out to be surprising that the Victorian wooden houses were not destroyed, and some new brick houses also survived.
The earthquake was felt over 1,170 kilometers: in the north up to Oregon, in the south - to Los Angeles. In general, tangible fluctuations covered an area of about one million square kilometers.
Today San Francisco is a city of over three million people. In it, in 1937, through the Golden Gate, engineers and architects ventured to build the longest suspension bridge in the world - 2737 meters, with two steel four-stage frame pylons, each 227 meters high. Later, an earthquake-resistant 48-storey Transamerica skyscraper appeared in the city, capable, according to design engineers, withstand earthquakes of any strength.
San Francisco still feels light tremors (about 23 impacts per year), but nothing tragic has happened to these largest high-rise buildings. To date, small movements of the San Andreas Fault have not done any tangible harm to San Francisco and its inhabitants. Apparently, this is due to the experience of construction that engineers and architects took out from the catastrophe of 1906. After this devastating earthquake, all new buildings under construction have a frame of special strength (in some cases, it is even made flexible), the foundation under high-rise structures is calculated so that it can withstand an earthquake of up to several points. When, during the 1979 earthquake, the strength of the tremors in the San Francisco area reached 5.9 points, they did not cause any catastrophic destruction to the city.
However, the San Andreas Rift, which continues to scare scientists, pleases false prophets. The rift played a major "role" in one of the American super-fighters. The protagonist of this film, a kind of genius mind of our century, is buying up all the desert lands around the fault for a pittance, and no one understands why he is doing it. Meanwhile, it is assumed that with the help of the impending nuclear explosion, the rift will set in motion and cause the split of the entire American continent. The devilish intrigues of this genius monster are thwarted by another superhero, who with his superpower neutralizes the atomic charge and prevents a catastrophe.
The plot of this action movie is rather meager, but it shows to what extent the thought of the danger associated with the San Andreas Fault lives in the minds of Americans. This was greatly facilitated by the demonstration on American television of a documentary about San Francisco, entitled "About the city that must die." Scientists are very serious about what could have happened if an earthquake as strong (as in 1906) struck a city of several million people today. Some of them believe that sooner or later a catastrophe will still happen and the San Andreas Fault will completely destroy the city.
N. A. Ionina, M. N. Kubeev