The San Andreas Fault Line

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The San Andreas fault line has causes constant development nightmares for large urban areas such as San Francisco and any other city that has been built on top of it. Fault lines are one of the side effects of the earth’s tectonic plates shifting that can result in devastating earthquakes. Some of the most devastating earthquakes in our modern era have occurred along the San Andreas fault line due to a dense population. The most notable earthquake on the San Andreas fault line occurred in San Francisco on 1906. The 1906 San Francisco earthquake was the most devastation of the earthquakes along the fault line due to its magnitude and the city’s ill preparedness. This earthquake and earthquakes to follow have been huge factors in how the city has been constructed and developed around the fault line. The earth’s outer layer is made up of several plates that are constantly moving. The movement of these plates results in three different types of boundaries: convergent boundaries, the plates move into each other; divergent boundaries, the plates move apart; and transform, where the plates move parallel to each other. Fortunately, all of the movements around these boundaries are incredibly slow and very rarely result in drastic natural phenomena, but when they do “act up” they can be very devastating. Each boundary has very specific natural side effects to their collisions. When two plates are convergent there are two possible consequences: one of the plates dives beneath the other one where it gets melted in the earth’s hot core and spit out later in a volcano, or the two plates collide rising up and turning into what we call a mountain. Two plates become divergent when hot magma from the mantle starts to rise pushing apart the plates ... ... middle of paper ... ... laws. Scientist made the assessment that the buildings with reinforced concrete and steel framed buildings fared the best under the pressure of the earthquake. With this in mind the city began pushing reinforced concrete and steel buildings onto every building built. The city also enacted a lateral wind load requirement of 30 pounds per foot, which was found to be the amount that would be able to withstand an earthquake. Many of the other building codes adjustment were thwarted by some interest groups, so companies would not be discouraged from building in San Francisco. They were able to sell that most of the damage to San Francisco was done by the fire and that the earthquakes damage was very minor. San Francisco would have to wait until 1925 to employ all of the proper building code to prepare for earthquakes, when the Santa Barbara earthquake hit San Francisco.
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