Earthquakes
Earthquakes are not a "sign of 2012"

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There is no question that there have been a lot of earthquakes recently. But, is the number of earthquakes larger than normal? Are the earthquakes getting stronger, as some people have been claiming?

USGS

According to the USGS website[1] we expect that earthquakes will occur in the following frequency:

Magnitude No. per Year Examples
8 and higher 1 Japan 2011 (8.9), Chile 2010 (8.8), Chile 1960 (9.5), Alaska 1964 (9.2)
7 - 7.9 17 Haiti 2010 (7.0)
6 - 6.9 134 Loma Prieta, CA. 1989 (6.9)
5 - 5.9 1319 Virginia, USA 2011 (5.8)
4 - 4.9 13,000
3 - 3.9 130,000 Illinois 2010 (3.8)
2 - 2.9 1,300,000

In Addition, the USGS has graphs of earthquakes statistics, including deaths, dating back to 1980 on this page1.

Earthquakes not on the Rise.

The claim that the number and intensity of earthquakes are "on the rise" is directly disputed by the USGS. From the USGS website[2]:

Are Earthquakes Really on the Increase?

We continue to be asked by many people throughout the world if earthquakes are on the increase. Although it may seem that we are having more earthquakes, earthquakes of magnitude 7.0 or greater have remained fairly constant.

A partial explanation may lie in the fact that in the last twenty years, we have definitely had an increase in the number of earthquakes we have been able to locate each year. This is because of the tremendous increase in the number of seismograph stations in the world and the many improvements in global communications. In 1931, there were about 350 stations operating in the world; today, there are more than 8,000 stations and the data now comes in rapidly from these stations by electronic mail, internet and satellite. This increase in the number of stations and the more timely receipt of data has allowed us and other seismological centers to locate earthquakes more rapidly and to locate many small earthquakes which were undetected in earlier years. The NEIC now locates about 20,000 earthquakes each year or approximately 50 per day. Also, because of the improvements in communications and the increased interest in the environment and natural disasters, the public now learns about more earthquakes.

According to long-term records (since about 1900), we expect about 17 major earthquakes (7.0 - 7.9) and one great earthquake (8.0 or above) in any given year.

Chile

Chile Earthquake

Haiti

Haiti Earthquake

Illinois

Illinois Earthquake

Sumatra (2004)

Sumatra Earthquake

Virginia (August 2011)

Virginia Earthquake

Why do some earthquakes disappear from the USGS maps?

Some 2012 proponents2 have claimed that the USGS deletes or hides earthquake data.

It is true that earthquakes can sometimes appear on the USGS maps and then later disappear, often within minutes. However, the USGS has CLEARLY EXPLAINED why this happens. Below is a shortened version of the article in the USGS F.A.Q. in the section Earthquakes » Latest Earthquake Map & Information.

Occasionally our systems produce erroneous information that is released to the public. These mistakes are generally promptly identified by seismologists and removed from our web pages.

In the interest of rapidly providing earthquake information to the public, information is automatically posted to the web. There is a trade-off between the speed of our earthquake notifications and number of false alarms in the same way that any kind of "breaking news" story may have substantial changes or corrections as more information is received. The faster we release earthquake locations and magnitudes, the more likely it is that the information may be erroneous [and require later correction]. However, experience demonstrates that imposing more restrictive quality standards prevents the release of legitimate earthquake information.

2012 proponents have complained that multiple earthquakes are sometimes reported, which later only appear as a single earthquake. These multiple reports are usually of very similar magnitude, which should give a clue that they are in fact just duplicates of the same earthquake.

Following large earthquakes, location algorithms can misidentify reflected and refracted seismic waves created by a single earthquake. In this case, one earthquake can turn into "events" located in areas far from the earthquake.

In other cases, noise in telephone circuits that bring the data from seismometers to computers can be misidentified as earthquakes. Adding to this complexity, there are multiple seismic monitoring networks that contribute their earthquake locations and magnitudes to the ANSS system. These networks use different data and algorithms to locate the earthquakes,and sometimes the spatial separation of the contributed locations is so large that our systems interpret the independent solutions as distinct earthquakes of similar magnitude and location [later corrected to show a single earthquake].

We are continuously improving our systems to reduce the number of false alarms. However, with the advent of rapid distribution methods, our errors are more widely seen and more difficult to retract completely. For these reasons, it is very important to remember that this data is preliminary and users should check our web site for the most recent updates.

Conclusion

In conclusion: Earthquakes are not becoming more frequent. Earthquakes are not becoming more intense. There is 110 years of data from the United States Geological Survey which shows that there is no increase in the size or number of earthquakes. There is no reason to expect that 2012 will be anything than an ordinary year as far as earthquakes.


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