Indiana not immune to major quakes
The world has seen its fair share of devastating earthquakes so far in 2010. The disaster in Haiti in January destroyed thousands of homes and left more than 222,000 dead. The U.S. Geological Survey (USGS) ranks it as the fifth deadliest on its list of the most destructive quakes on record. Since then, Taiwan and Turkey have also experienced earthquakes and an offshore quake in Chile registered an 8.8 magnitude, making it one of the strongest on record.
Though it seems likely that these many worldwide seismic incidents must somehow be related, science professor J. Thomas Howald said it is simply a coincidence. He explained that it is unlikely that one earthquake would cause another; instead, they tend to cause tsunamis or nearby tremors.
Howald previously worked at Indiana University’s Judson Mead Geologic Field Station in Montana.
He said Haiti is a hot spot for earthquakes. The island is located where two tectonic plates are moving transversely past each other. However, the country’s government does not enforce proper building regulations, which helped make Haiti a far greater disaster than the much stronger Chilean earthquake, Howald explained.
The recent slew of earthquakes raises local concerns. Indiana is certainly associated with the infamous Tornado Alley, but is not usually considered susceptible to earthquakes. However, the Midwest is the site of the most severe earthquakes in U.S. history. They occurred in 1811 and 1812 as a series of shocks in Arkansas and Missouri, which were so strong they "rang church bells in New York and Philadelphia," Howald said.
The central United States is home to the New Madrid seismic zone, which is centered in Missouri and stretches into Kentucky and Illinois. This earthquake region is not well understood and Midwestern quakes are difficult to predict because the region sees so few low-magnitude earthquakes, which act as a warning of more severe disasters, according to the USGS.
A USGS report estimates the probability of a Midwest earthquake of 7.5 to 8.0 magnitude at 7 to 10 percent for the next 50 years. However, the likelihood of a magnitude 6.0 earthquake in the region is as high as 40 percent.
The great length and frequent seismic activity of the San Andreas Fault makes California the most famous earthquake spot in the U.S., Howald said. Indiana is not located on a major fault line like California, but a branch of the New Madrid fault runs through the state, he said.
Recent measurements of the apparent lack of ground movement in the New Madrid zone has led some scientists to declare that it is "shutting down", but a USGS report maintains that these measurements are faulty and the Midwest is still at risk for earthquake activity.
The report stated that future earthquakes in the Midwest would cause bridge failures, disruption of agriculture, contamination of rivers and streams and flooding of the Mississippi River. Many Midwestern cities would also sustain significant damage.
