How can my family be prepared for an earthquake? This question haunts countless residents in the Los Angeles area every day. Hopefully we here at the Earthquake Preparedness Center can shed some light on how you can protect your family. My name is Darin Fort and I am the Director of Earthquake Preparedness for Los Angeles. As with any danger, knowledge of the event is of upmost importance. Some questions that should be asked by anyone who wants to defend their home against earthquakes are: What are the origins and causes of earthquakes and what is the relation of earthquakes to plate tectonics and faults in Los Angeles? What are some historical disasters associated with earthquakes? What are the hazards associated with earthquakes? What is the potential for future earthquakes in the Los Angeles area?
Earthquakes are started at the Earth’s crust. Our planet is made up of different plates which float on a layer of molten material or magma much like potato chips would float on top of a bowl of water. Scientists believe there could be as many as 12 plates that make up Earth’s crust. These plates move freely like bumper cars: pulling away from each other, moving side to side or laterally, and even smashing into each other. The proof behind plate tectonics lies in mountain ranges and island chains like the Hawaiian Islands, both are products of plate tectonics. Earthquakes originate from plate boundaries called faults. The tension and movement between the conflicting faults is what causes the shock waves referred to as an earthquake. When the pressure between two conflicting plates is too much for the rock material to support, they can shift or break dramatically. The exact underground point where this occurs is the focus. Many people are familiar with the above ground version of the focus called the epicenter. When the plates crack or shift, shock waves are sent out from the focus.
The Essay on Vertical Displacement Earthquake Plate Anchorage
The Alaska earthquake of 1964 and following tsunami took 125 lives (tsunami 110, earthquake 15), and caused about $311 million in property loss. It is the biggest earthquake ever measured with an intensity of 9. 2 on the Richter Scale. Earthquake effects were big in many towns, including Anchorage, Chitin a, Glenn allen, Homer, Hope, Kasi lof, Kenai, Kodiak, Moose Pass, Portage, Seldovia, Seward, ...
These waves come in three forms: Primary, Secondary, and Surface. The surface wave is the one which causes damage to our cities and homes. Unfortunately, Los Angeles is located over an earthquake hot bed. There are two different kinds of plate boundaries located under the Los Angeles area. The first is called a transform plate boundary. In a transform boundary, such as the San Andres Fault, plates move in a lateral motion. Imagine taking two pieces of rough cut wood and sliding them against one another. When the force applied exceeds the ability of the splinters holding them together, they slip and then catch again when it meets new, stronger material. This is called strike-slip affect which is produced by transform plate boundaries. The other type of boundary located in the Los Angeles area is called a convergent boundary. Convergent boundaries are located where two plates are colliding into each other.
The grinding and crushing action of the two converging plates send shock waves out just as the transform boundary does. Los Angeles has been battling the effects of plate tectonics for centuries. The Los Angeles area has suffered several major events in recent history. The Fort Tejon Earthquake took place in 1857 and tremors from this quake were felt over 350,000 square kilometers (USGS, 2012).
The Fort Tejon Earthquake was one of the largest in California history and originated at a strike-slip boundary. The Parkfield Earthquake of 1901 was an event we all hope never happens again. Over 700 people lost their lives that day due to the tremors which originated from the San Andres Fault (USGS, 2012).
In 1994 a major event struck which killed many, injured thousands, and destroyed billions of dollars’ worth of property. There were also major events which took place in 1881, 1922, 1934, 1966, and most recently 2004 where property was damaged and even worse lives were lost.
The Essay on Some wonderfull events in my life
Everybody in the world is pass from different and various events during his/her lives. I also observed and pass through the many events from my childhood up to present now. As I grow up I perceives knowledge form the education, nature, etc. He enjoys events or occasion, makes friends, etc. Friends are very important in ones life because friends are responsible to give shapes of ones life. I got a ...
The hazards involved in an earthquake are countless. As stated earlier, the major damage causing force of an earthquake is the surface wave. The surface wave causes ground tremors that can knock building off their foundations and bring bridges crumbling down. If you are inside, either find the strongest area of the room or get under a table or desk and stay there. If you are caught outdoors get into the open, as far away from buildings, power lines, or any other type of tall or overhead structures. Another major hazard brought about by an earthquake is fire. Many times tremors from earthquakes can bring down power lines and rupture gas mains. In an event where you witness fallen power lines or leaking gas main, please move as far away from them as possible and contact rescue personnel as soon as possible.
Crumbling dams and levees can also lead to flooding in some areas. Stresses in certain structures like dams and levees tend to not present themselves until it is too late to escape the rising water. You should evacuate the area until safety and rescue personnel have had time to clear the area and inspect the affected structure. We can say, without hesitation, the earthquake activity in the Los Angeles is here to stay. Since we are located directly over plate boundaries, we will continue to see seismic events. Plate tectonics, the driving force of earthquakes, is a natural process which has formed the ever-changing world we live in today. Science Daily, a leading publisher of science news, recently published an article titled “California Has More Than 99% Chance of a Big Earthquake within 30 Years, Report Shows” (Science Daily, 2008).
While the actual statistic is a 49% chance of a 7.5 or greater earthquake striking in the next 30 years, we are certain that seismic events will continue to plaque the city (Science Daily, 2008).
The Essay on Earthquake Studies For Southern California
Earthquake Studies For Southern California EarthquakeCountry.info claims that earthquakes are as Southern Californian as waves at the beach and traffic on the freeways. Lets dwell on earthquakes in Southern California as well as the faults associated with our area. The San Andreas fault is one of the most significant faults affecting our area. We know that the San Andreas fault produces large ...
Unfortunately, many of the lives lost in earthquake events could be prevented by taking precautionary steps in our everyday lives. However, due to an increased population and congested city centers it is possible there could be more lives lost today if a major event were to strike. Please take all precautionary measures to keep you and your family safe during an earthquake. For a full list of ways to keep safe before, during, and after an earthquake, please visit www.consrv.ca.gov , click on “Earthquakes” and follow the link to “What to do if an earthquake strikes”. Remember, being prepared may save your life.
Reference Page
California Department of Conservation. (2007).
What to do in an Earthquake. Retrieved from
http://www.consrv.ca.gov/index/Earthquakes/Pages/qh_earthquakes_what.aspx ScienceDaily. (Apr. 15, 2008).
California Has More Than 99% Chance Of A Big Earthquake Within 30 Years, Report Shows. Retrieved from
http://www.sciencedaily.com/releases/2008/04/080414203459.htm USGS. (2012).
California Earthquake History. Retrieved from
http://earthquake.usgs.gov/earthquakes/states/california/history.php USGS. (2012).
1857 Fort Tejon Earthquake. Retrieved from
http://earthquake.usgs.gov/research/parkfield/1857.php
USGS. (2012).
1901 Parkfield Earthquake. Retrieved from
http://earthquake.usgs.gov/research/parkfield/1901.php
