Friday, June 24, 2011

Janet Woods' view on Earthquakes

Environmental Studies PHS 100A
Warner Pacific College
June 23, 2011

Natural Hazards:

Earthquakes
I have never experienced a natural disaster or hazard. There have been times when natural disasters have occurred within a fifty mile radius of where I lived. I was raised in southern California where earthquakes seem to be a part of everyday life. Yet there were only a few that stand out in my memory.
The first earthquake that I remember occurring happened the day after my tenth birthday. The epicenter was in the San Fernando Valley. The magnitude of the quake was 6.6 and was felt throughout southern California, western Arizona and southern Nevada. The quake lasted approximately sixty seconds, but did extensive damage and sixty-five people died and over two thousand people were injured. A newly built, earthquake resistant, hospital collapsed, freeway over passes collapsed, freeway asphalt buckled. Landslides caused extensive damage in areas where fault line activity had not been observed prior to the 1971 quake. I remember traveling, with the family, driving north almost a year later and still seeing the broken asphalt off to the side of the interstate. It was estimated the quake caused in excess of five million dollars damage.
There were many quakes felt throughout the years growing up; but none held the emotional response as the San Fernando quake. Another quake that holds a memory happened on the evening of my son’s birth. My sister had come to the hospital to visit and we had the news on the television and the newscasters reacted in the same way we did in questioning whether that was a quake. The quake was 6.2 magnitudes and was just a foreshock. Early the next morning a 6.7 quake was felt throughout southern California. The epicenter was near the Imperial Valley. This quake rolled for what seemed like several minutes but only lasted approximately a minute. This quake caused the damage to the walls of the canals in the Southern California Irrigation systems. There were only two deaths reported in this quake but over six hundred thousand dollars damage to the irrigation systems.
Earthquakes happen due to the shift in the layers of the earth. The heat from the inner layers of the earth cause shifts “drives convection currents that flow in loops in the mantle, pushing the mantle’s soft rock cyclically upward (as it warms) and downward (as it cools),” (Withgottt, 2011p.35). These shifts cause changes to the earth’s surface. These changes affect not only the man made materials; it also affects the entire ecosystem of the area; sometimes permanently altering the area.
Nothing I have been through comes close to the devastation cause by the earthquake in Haiti. The estimated loss of life in is two hundred thirty thousand people. There are still many people who do not have a place to live. Tourism was a major part of the economic system for the Haitian people and so much was destroyed; the tourism trade is not recovering quickly enough.
Another earthquake that has caused massive destruction occurred recently in Japan. The country was not only affected by the earthquake, but they were also hit with devastating tsunami. The tsunami wiped out entire villages, changing the countryside forever.
The environment is changed in the surrounding areas of the epicenter. Sometimes there are able to recover given enough time. Other areas will have extreme difficulty in recovering from the changes in the eco-system.

References
http://earthquake.usgs.gov/earthquakes/states/events/1971_02_09.php retrieved June 21st, 2011.
http://earthquake.usgs.gov/earthquakes/states/events/1987_11_24.php retrieved June 21st, 2011.
Withgott, J., & Bennan, S. (2011). Environment: the science behind the stories (4th ed.). New York. Pearson Benjamin Cummings.

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