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1906 San Francisco Earthquake

1906 San Francisco Earthquake
San Francisco, a major city of the United States experienced one of the most devastating earthquakes in its history in 1906. Find out some important information about this earthquake, through this ScienceStruck article.
Chandramita Bora
The great earthquake that shook San Francisco on April 18, 1906, is one of the most devastating earthquakes in the history of the United States. The epicenter of this crushing earthquake was 2 miles away from the city of San Francisco. It affected an estimated area of 375,000 square miles, covering Coos Bay in Oregon, to Los Angeles and as far as Central Nevada.
The San Francisco Earthquake
The earthquake was caused by a break on the San Andreas Fault, which runs through California, and covers a distance of 800 miles, from Salton Sea to the south and Cape Mendocino to the north. The earthquake devastated 296 miles of northern segment of the fault. The first tremor was felt around 5.12 am in the morning throughout the bay areas of San Francisco. About 20 to 25 seconds later, the earthquake wrecked havoc with an estimated magnitude of 7.8 on the moment magnitude scale, and 8.5 on the Richter scale.
Coupled with the consequent fire, which was caused by the rupture of the gas mines, the earthquake ravaged almost the entire city. The condition of the city was further worsened when inexperienced firemen attempted to create firebreaks by demolishing buildings with the help of dynamite. Instead of preventing the fire, the demolished buildings helped the fire spread further. The fire itself destroyed almost 25,000 buildings, and burnt for almost four days. In fact, the fire was estimated to be the cause of almost 90% of the total damage. Moreover, water mains were also destroyed by the earthquake, leaving few resources in the hands of the fire department.
Though initially the official estimates of death tolls were 376, later that figure went up to 3,000. Most of the casualties were reported from the city of San Francisco, while 189 were reported from the bay areas. Besides San Francisco, other cities like Santa Rosa, San Jose, and Stanford were also affected by the earthquake. Before the earthquake, the total inhabitants of San Francisco were 410,000, of which almost 225,000 to 300,000 people were rendered homeless. The loss of property was estimated to be more than $400 million.
The earthquake was so strong that it changed the course of the river Salinas, the largest river of the central coast of California. It left a lasting impression on the city of San Francisco, which was the ninth largest city of the United States, and one of the most important centers of culture and trade before the earthquake. The earthquake destroyed almost 80% of the city, which halted the growth and development of the city.
Immediately after the earthquake, rehabilitation and reconstruction plans were devised. Contributions poured from countries like England and Canada. Many citizens and business enterprises also contributed to the relief efforts. But these were not sufficient, and so, ultimately the burden of reconstruction fell on the shoulders of the rich members of the society. The insurance companies had to pay a staggering amount of $235 to $265 million for fire damage.
The earthquake of 1906 was so menacing that it left a long-lasting effect in the country, especially in San Francisco. It is still remembered by the people of the United States, and recently, its centenary was commemorated in 2006, which was attended by eleven survivors.