October 19, 2012 – Major Global Earthquakes Over the Last 4,000 Year: I downloaded global earthquakes, from 2150 B.C. to 2012 A.D. greater than or equal to 7.0 magnitude, from the NOAA database. The total number of quakes retrieved was 1,462. I graphed the earthquakes by month, as shown above. Some of the older tremors did not have months listed; therefore, there are a total of 1,438 earthquakes shown on the graph. For example, the low month was April with 104 and the high month was November with 145. The green line is an exponential trend line.
What surprises me is the variability among months. With a sample this large I was expecting a more equal distribution. November, with 145 quakes, is more than two standard deviations away from the mean; which makes it a statistical oddity. Something else is at work here and I do not know what it is.
The first quake occurred in 2150 B.C. in southwestern Syria and was a 7.6 magnitude quake that killed 7,300. The last quake occurred September 30, 2012 in Southern Colomiba in the province of Cauca.
These 1,462 earthquakes produced 5.2 million deaths, 1.4 million injuries, $481 billion in damages, destroyed 7.8 million houses and damaged another 7.2 million.
The maximums in each category are as follows: (1) Deaths 1.1 million on May 20, 1202 in southwestern Syria – 7.6 magnitude, (2) Injuries 374 thousand on May 12, 2008 in Sichuan Province, China – 7.9 magnitude; (3) Damages $210 billion on March 11, 2011 off the east coast of Honshu Japan – 9.0 magnitude, (4) Houses Destroyed 5.2 million Sichuan Province, China and (5) Houses Damaged 5.2 million Sichuan Province, China. The highest numbers in three out of five categories occurred during the Sichuan Province, China 7.9 magnitude quake because it occurred at a very shallow 19 kilometers (12 miles).
The highest monetary damages were from the tsunami generated in the Japanese mega-quake in 2011. This illustrates several important points: (A) An earthquake can wreak havoc if it is shallow and close to a populated area, (B) The tsunami generated by the quake can be far more destructive than the quake itself, and (3) Other after effects can be even more destructive than tsunamis, e.g. the fire that destroyed San Francisco after the April 18, 1906 quake.
The Master of Disaster