August 16th, 2005 09:42 EST
A powerful earthquake measuring 7.2 on the Richter scale struck the north-east coast of Japan today injuring at least 59 people, as well as shaking skyscrapers 186 miles away in Tokyo, suspending train services as well as postposing flights. This was the second major jolt in three weeks.
A tsunami warning was issued for Sendai harbour and withdrawn later in the day after two waves cresting at 10 centimeters high hit the coast of Miyagi prefecture coast near Sendai.
However, a much larger earthquake threat could be looming. According to several Geologists from the University of Memphis, strong earthquakes in the New Madrid fault line are certain to take place in the future. Our greatest concerns are the 6.0-7.6 on the Richter scale and these large seismological events have a 90% chance of happening by the year 2040. "
The New Madrid fault line is located in the central Mississippi Valley, and extends from northeast Arkansas, through the areas of southeast Missouri, western Tennessee, as well as western Kentucky and southern Illinois. Historically, this area has been the site of some of the largest earthquakes in North America.
Almost two centuries ago on December 16, 1811, an extremely large earthquake struck within the central Mississippi Valley. This was the first of three magnitude-8 earthquakes and triggered thousands of aftershocks, which rocked the region.
According to the U.S. Geological Survey, during this time survivors reported that these earthquakes caused cracks in the earth`s surface, the ground to roll in visible waves, and large areas of land to sink and some to rise and it also changed the course of the Mississippi River, and reports by witnesses of the quake stated that church bells rang in Quebec and Boston.
The crew of the New Orleans (the first steamboat to operate on the Mississippi River, which was on her maiden voyage) reported mooring to an island only to awake in the morning and find that the waters of the Mississippi River had overtaken the island as a result of the powerful earthquake.
The journal Nature reported in June 2005 that a University of Memphis study detected a half-inch of fault shift in the past five years. The movement, detected with a global positioning system, could mean pressure is building toward a significant quake in that region, which is currently populated by millions of people.
Geologists say the odds of another 8.0 event within 50 years are between 7 and 10 percent and the causes and effects of earthquakes in the central and eastern United States are just beginning to be understood. Through better understanding of earthquake hazards and through public education, earth scientists and engineers are helping to protect the citizens of all parts the United States from loss of life and property in future earthquakes. Currently at the forefront of earthquake prediction technology is the San Andreas Fault Observatory at Depth (SAFOD). According to http://www.usgs.gov/newsroom/article.asp?ID=854 on August 2, 2005, they achieved a primary goal when scientists drilled into a seismically active section of the fault approximately two miles below the surface of the Earth.
When completed in 2007, SAFOD will be the only earthquake observatory with instruments installed directly within an active fault where earthquakes form or "nucleate. " Scientists also will be able to bring up actual rock and mineral samples from the earthquake zone. "
This experiment has opened doors to subsequent research that will greatly improve capabilities in predicting large size seismological events as well as aiding engineers in the development of earthquake friendly structures.
Some earthquake safety tips and procedures may be found at the National Disaster Education Coalition http://www.disastercenter.com/guide/earth.html.