Tuesday, February 5, 2008

Real Seismic Activity


I decided to investigate what the actual effects of an Earthquake are. Here is what howstuffworks.com (my favorite website when I need to know the basics on anything) has to say about earthquakes and their impact:


Every year, earthquakes cause thousands of deaths, either directly or due to the resulting tsunamis, landslides, fires, and famines. Quakes occur when a fault (where Earth's tectonic plates meet) slips, releasing energy in waves that move through the ground.
Scientists measure the strength of tremors on the Richter scale, which assigns magnitude in numbers, like 6.0 or 7.2. A 5.0 tremor is equivalent to a 32-kiloton blast, nearly the explosive power of the atomic bomb dropped on Nagasaki in 1945! Going one whole number higher -- such as from 5.0 to 6.0 -- reflects a tenfold increase in the amplitude of waves. Here are some of the most destructive earthquakes in recent history.


Missouri: December 16, 1811 The New Madrid fault -- near where Missouri, Kentucky, Arkansas, and Tennessee meet -- witnessed an 8.0 or greater magnitude quake nearly 200 years ago. The shaking spread so far that church bells reportedly rang in Boston, more than 1,500 miles away! It had dramatic effects on the area's geography, lifting up land enough to make the Mississippi River appear to flow upstream. Fortunately, the sparsely populated area suffered only one death and minimal property damage.
The Great San Francisco Earthquake caused $524 million in damage and killed 3,000 people.

San Francisco: April 18, 1906 The Great San Francisco Earthquake -- a 7.8 magnitude tremor -- brought down structures across the Bay Area. In San Francisco, buildings crumbled, water mains broke, and streetcar tracks twisted into metal waves. But the majority of the 3,000 deaths and $524 million in property damage came from the massive post-tremor fire, which spread rapidly across the city in the absence of water to quell the flames. People as far away as southern Oregon and western Nevada felt the shaking, which lasted nearly a minute. 3. Southern USSR: October 5, 1948 This earthquake in Ashgabat, Turkmenistan, killed around 110,000 people, more than two-thirds of the city's population at the time. The 7.3 magnitude rumbling reduced much of the city to rubble and was one of the most devastating quakes to hit Central Asia. In 2002, the government of Turkmenistan commemorated the devastating event by issuing special coins featuring images of President Suparmurat Niyazov and his family members -- most of whom died in the 1948 quake.


Southern California: January 17, 1994 The 6.7 magnitude Northridge tremor left 60 people dead and caused an estimated $44 billion in damage. The rumbling damaged more than 40,000 buildings in four of California's most populated and expensive counties: Los Angeles, Orange, Ventura, and San Bernardino. The earthquake, which was felt as far away as Utah and northern Mexico, luckily struck at 4:30 a.m., when most people were not yet populating the region's crowded freeways, office buildings, and parking structures, many of which collapsed.

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