March 1, 2014 – California is Overdue for the “Big One:” The San Andreas Fault, pictured above, cuts through California like a “knife of doom!” When will it slice off the coast of California? My guess would be between April 2014 and 2017. A study performed by geologists, showed that the San Andreas Fault releases a big quake about every 150 years. The last big quake in Southern California was on January 9, 1857 (1857 + 150 years = 2007); estimated at 8.2 magnitude. The last big quake in Northern California was in San Francisco on April 18, 1906 (1906 + 150 years = 2056); projected at 8.3 magnitude. Therefore, we’re within the time frame for “The Big One.”
Except now, the greater Los Angeles area is home to over 16 million people and the Bay Area of San Francisco about 8 million. So, when the big one comes; it will be catastrophic if it hits either one of these mega cities. Since the S.F. quake was 108 years ago and the L.A. quake was 157 years ago; Southern Calif. is the most likely place for “The Big One.” In fact, Southern California is overdue by 7 years (1857 + 150 = 2007 – 2014 = 7 years).
However, most people think that earthquakes are increasing in strength and quantity. Part of the reason for this is more reporting stations and better worldwide communications. For example, in 1931 there were about 350 seismograph stations 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. Therefore, it just seems like the number of earthquakes are increasing.
The United States Geological Survey (USGS.gov) says that according to long-term records (since about 1900), we can expect about 15 major earthquakes (7.0 to 7.9 magnitude) and one great earthquake (greater than 8.0) in any given year. So far, in calendar year 2014, we’ve had six quakes in Jan-2014 (largest 6.5) and nine in Feb-2014 (largest 6.9).
The Master of Disaster
Here are the lastest Frequency of Occurrence of Earthquakes from the USGS in terms of magnitude ranges and average annual events:
8 and higher = 1
7 – 7.9 = 15
6 – 6.9 = 134
5 – 5.9 = 1,319
4 – 4.9 ~ 13,000
3 – 3.9 ~ 130,000
2 – 2.9 ~ 1,300,000
These numbers are based on observations since 1900 by the USGS.
The Master of Disaster
Here are the results of a study I did July 16, 2011 on the number of earthquake, worldwide, from 2000 through July 16, 2011; in terms of number of earthquakes per year and their average magnitude:
Year Qty Magnitude Comments
2011 12 7.43 Only thru 7-16-2011
2010 23 7.33
2009 18 7.46
2008 12 7.29
2007 18 7.57
2006 11 7.48
2005 11 7.45
2004 16 7.36
2003 15 7.37
2002 13 7.45
2001 16 7.39
2000 15 7.43
What strikes me odd about this data is, that no matter how many earthquakes their are in any given year, the average magnitude remains around 7.4 with very little variance. For example, even this year (2011) with the great 9.0 Japanese earthquake, the average is still 7.43.
The total for the 12 year period (2000 thru 7-16-2001) is 180 quakes. The average per year is 15, the greatest in any year was 2010 with 23 and the least in any year(s) was 11 in 2006 and 2005. The average magnitude for all 12 years was 7.45 with the greatest average mag. year of 7.57 in 2007 and the least magnitude year was 2008 at 7.29.
The Master of Disaster