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 Earthquake Insurance

Earthquakes are not a frequent occurrence in the United States, but they are devastating when they do strike. For those areas most vulnerable, this risk is far too high and worth preparing for.

There have been 3 magnitude 6 or higher earthquakes in the US so far this year: a 7.9 earthquake on the San Andreas Fault in Southern California; an 8.3 earthquake on the Caribbean coast of Mexico; and a 5.8 earthquake in Virginia that shook D.C., Baltimore, Philadelphia, and New York City (the largest Eastern US quake since 1755).

So how do we handle earthquakes? First, there are different types of earthquakes, but the most important distinction is between those that originate below and above ground.

Below Ground Earthquakes : These are caused by stresses along major fault lines within the Earth. Three fault lines run through Illinois, one of which runs directly under Springfield. These can be devastating because they occur beneath the surface, so even if buildings appear to be in good condition they may not be safe after an earthquake. The 1989 San Francisco earthquake killed more than 700 people and injured nearly 3,000 more, and caused $20 billion in damage when it struck just before dawn on October 17th. The earthquake was centered about 30 miles east of San Jose in northern California. It hit 6:22 a.m., less than an hour before the crack of dawn. The quake was six times more powerful than the 1989 Loma Prieta earthquake, which hit the Bay Area just two weeks earlier, on October 17th. That quake rumbled through the Bay area, but it is estimated that 40% of Marin County and all of Berkeley were not damaged by earthquakes.

Widespread Damage - Such quakes are usually limited to one region alone, such as California's destruction in 1989 (not to be confused with California's still-ongoing drought). In the East, the most powerful quake since 1700 was centered in Virginia in 2011, when an earthquake measuring 5.8 on the Richter scale shook D.C., Baltimore, Philadelphia and New York City with its strongest tremors. The quake struck at 1:51 p.m. EDT in a rural area near Louisa, Va., about 64 miles west-southwest of Richmond and 47 miles northeast of Charlottesville . The earthquake had a depth of 4.3 miles and was centered about 13 miles from Mineral, Va., where there is also a nuclear power plant that was not damaged by the quake. The earthquake had a magnitude of 5.8 and was felt as far away as Richmond, Virginia, the District of Columbia and Pittsburgh, Pa. The earthquake was the largest seismic shock in the region since 1755 and occurred about a week after an earthquake in Japan with a magnitude of 5.6.

Ground Motion - Earthquakes are measured by measuring how much the ground moves during an earthquake. Depending on where in the country you are, you can expect to feel different levels of ground shaking based on what type of fault lines they are on or if they have recently experienced an earthquake (example: In 2011 a 5.4 RichterQuake struck near Lolo Pass).

Groups - Earthquakes can be grouped into three main categories, depending on what type of damage they cause:

Primary Damage - Earthquakes result in damage to buildings and other structures. The 1989 Loma Prieta earthquake in the Bay area cost an estimated $19 billion just in property loss, even though it was felt around the world. It was centered about 24 miles west-southwest of Big Sur, Calif., and had a magnitude of 6.9. This deadly earthquake is estimated to have caused $17 billion in direct property loss and another $4 billion in business interruption losses from 1989 to 1995.

Secondary Damage - Earthquakes are usually accompanied by landslides, mudslides and other geological events such as soil liquefaction. In 1971, an earthquake in Peru caused a landslide that killed more than 70,000 people and left 100,000 others missing.

Tertiary Damage - Earthquakes can cause fires if they strike areas containing flammable chemicals or gasoline storage tanks. On October 17th of 1989 in Northern California an earthquake struck at 6:22 AM that was centered about 30 miles east of San Jose in the Santa Cruz Mountains. The Loma Prieta quake was named for the Santa Cruz Mountains, where it struck, and the Loma Prieta pass near where U.S. 101 crosses through the mountain range. As the earthquake struck, a section of a double-decker eastern span of the Bay Bridge, which was under construction, collapsed sending cars and their occupants into the waters of San Francisco Bay. Fires broke out in many parts of the East Bay area before emergency response teams could reach them; several injured people died when they were unable to leave their homes. In this after photo you can see the crumbled portion where so many people lost their lives at what is known as "the crooked section" of Highway One.

So How Safe are My Buildings?

The March 2011 earthquake in Japan had an 8.9 magnitude and was the fifth most powerful earthquake in history. It occurred at about 19:41 local time (06:54 UTC) at the northern end of the Kanto Plain, an area with a mix of urban and rural areas. It killed some 6,000 people and caused immense damage to many buildings, including Tokyo's national stadium, Tohoku University Hospital, Sendai Airport and Fukushima Daiichi Nuclear Power Plant. This earthquake left a 23-mile-long (37 km) rupture zone that extended to Lake Hamana in Miyagi Prefecture. The epicenter is located offshore from Tottori Prefecture’s Onagawa port city on the Pacific coast of Honshu island, Japan’s main island.

Seismic activity in Japan is caused by the motion of the Pacific tectonic plate under the Eurasian plate. The Tokyo area sits on a narrow coastal plain north of “Load and dip” zone, which is located on the west side of the main Honshu island. The “Load and dip” zone consists of a layer of soft sediments buried under hard rocks called Jogosha. On March 11, 2011 it experienced a M=6.2quake (the strongest earthquake ever recorded in Japan). The Tohoku earthquake was part of a chain of more than 100 events that struck along this zone on March 11th, producing jolts ranging from magnitudes 2 to 6.

Conclusion - In the case of an earthquake, it is always best to gather as much information as you can about your structures( e.g. location, access, age, etc..) before you go more into depth on how to prepare for the earthquake.

For More Information and Earthquake Resources Click Here:

http://www.earthquakesafety.