September 30, 2012 – Major Global Earthquakes by Country: The chart above summarizes the quantity of major earthquakes, greater than or equal to 7.0 magnitude, by country. The period covered is from January 1, 1973 to September 30, 2012.
Indonesia and Japan are # 1 and # 2. The Russian Federation was # 3, with almost all of those quakes occurring in or around the Kamchatka Peninsula and the Kuril Island Chain.
Two states, in the U.S.A. saw most of the major quakes: (1) Alaska – 12 and (2) California – 7. The U.S. Protectorate Guam had 4 and Idaho and Hawaii had one each.
The “80/20 Rule” holds true once again. The Pareto principle (also known as the 80–20 rule, the law of the vital few, and the principle of factor sparsity) states that, for many events, roughly 80% of the effects come from 20% of the causes.
Business-management consultant Joseph M. Juran suggested the principle and named it after Italian economist Vilfredo Pareto, who observed in 1906 that 80% of the land in Italy was owned by 20% of the population; he developed the principle by observing that 20% of the pea pods in his garden contained 80% of the peas.
It is a common rule of thumb in business; e.g., “80% of your sales come from 20% of your clients“. Mathematically, where something is shared among a sufficiently large set of participants, this rule seems to manifest. There is nothing special about the number 80% mathematically, but many real systems with a large number of cases (N) seem to follow the 80/20 rule.
Looking at the chart above of the top 12 countries, in terms of 7.0 magnitude earthquakes over the last 40 years the rule is almost spot on. There were 56 countries with quakes greater than or equal to 7.0 magnitude. The top 12 countries are shown in the chart above. Therefore, 80% of major global earthquakes occurred in 20% of the countries. The actual percentage is 21.4% (12/56 = 21.4%).
The chart above totals 246 major earthquakes in 12 countries. Total major quakes over the 40 year period were 358. Therefore, the quakes shown on the chart account for 68.7% of total quakes (246/358 = 68.7%).
The Master of Disaster