SAN FRANCISCO EARTHQUAKE-1906

By Jessica

HOW THE DISASTER SHOOK AMERICA

108 years later the San Francisco earthquake still stands as America’s worst natural disaster in history. With over 3 000 fatalities and almost 10 000 injuries it was a devastating experience for many. This brutal disaster left 400 000 homeless and many faced difficulty and hardship for several days.

THE EARTHQUAKEThe San Francisco Earthquake of 1906 hit San Francisco and Northern California on Wednesday, April 18th at 5:12am. The earthquake itself lasted for less than a minute, but it came with multiple uncontrollable fires that lasted for days. Because of this, there was an estimated 3 000 fatalities and over 80% of San Francisco was brutally destroyed. The survivors whose homes where destroyed slept in tents in city parks, stood in long lines for food, and were required to do their cooking in the street to minimize the threat of additional fires. The San Francisco earthquake is one of the worst natural disasters in U.S. history.

Before and After

HOW THE EARTHQUAKE STARTED

The North American plate, and the Pacific plate boundaries form what is called the San Andreas Fault. The Pacific plate is slowly moving northward, and is "locked" at the areas around Los Angeles and San Francisco. The central part of California’s plates are constantly moving 3/4 of an inch per year (1.9 Cm). The plate boundaries that are "locked", build up pressure and suddenly release causing a rough shake called an earthquake.

TECTONIC PLATES There are 3 primary types of Tectonic Plate Boundaries; Divergent, Convergent and Transform. To understand the boundaries, you must understand what each word means. Divergent means pulling apart, Convergent means coming together and transform is sliding against.

At divergent boundaries new crust is created as one or more plates pull away from each other. Oceans are born and grow wider where plates diverge or pull apart.

A convergent boundary is an actively deforming region where two or more tectonic plates below earth’s surface move toward one another and collide. As a result of pressure and friction, earthquakes and volcanoes are common near convergent boundaries

Transform Boundaries are where two plates are sliding horizontally against one another. These are also known as transform boundaries or more commonly as faults. The San Francisco earthquake was caused by the Transform Boundaries.

Model of Transform Plates

MAGNITUDE, LOCATION The magnitude of an earthquake shows you how rough of a shake it was. The scale ranges from 1-10; 1 being the least violent and 10 being very violent. The San Francisco earthquake hit with a powerful 7.8 magnitude. The epicenter of the shake was 2 miles off the coast of San Francisco near Mussel Rock. The shake was felt from Oregon to Los Angeles and all the way to Nevada. Despite the mass of the earthquake, there was no after-shocks or tsunamis.

THE SURFACE OF THE EARTH IS CONSTANTLY CHANGING

Everyday, Earth’s plates are constantly moving and changing. Some changes are less obvious while others are clearly moving. When the plates move, it changes the earth because the plates are no longer in their previous position. The changing of earth can take place in multiple ways such as weathering, volcanos, earthquakes and erosions. As a result, the earth is always finding new ways to change and move.

BIBLIOGRAPHY-WEBSITES

http://wikimapia.org/12201738/Epicenter-of-1906-San-Francisco-earthquake

http://www.archives.gov/legislative/features/sf/

http://www.platetectonics.com/book/page_5.asp

http://www.eyewitnesstohistory.com/sfeq.htm

http://en.wikipedia.org/wiki/San_Andreas_Fault

BIBLIOGRAPHY-PICTURES

http://www.platetectonics.com/book/page_5.asp

http://bernalwood.wordpress.com/2011/04/18/the-1906-earthquake-as-experienced-from-bernal-heights/

http://www.berkeley.edu/news/media/releases/2004/01/images/san_andreas_fault.gif

http://allanawheeler.files.wordpress.com/2011/05/mms.jpg

http://youtube.com