13 Crazy Earthquake Facts

 
1. Earth has been more seismologically active in the past 15 years or so, says Stephen S. Gao, a geophysicist at Missouri University of Science & Technology. Not all seismologist agree, however.

2. San Francisco is moving toward Los Angeles at the rate of about 2 inches per year — the same pace as the growth of your fingernails — as the two sides of the San Andreas fault slip past one another. The cities will meet in several million years. However, this north-south movement also means that despite fears, California won't fall into the sea.

3. March is not earthquake month, despite what some people believe. True, on March 28, 1964, Prince William Sound, Alaska, experienced a 9.2 magnitude event — one of the biggest ever. It killed 125 people and caused $311 million in property damages. And on March 9, 1957, the Andreanof Islands, Alaska, felt a 9.1 temblor. But the next three biggest U.S. earthquakes occurred in February, November, and December. The devastating major earthquake in Chile of 2010 struck on Feb. 27. And the huge 9.3 temblor that spawned the devastating Indian Ocean tsunami in 2004 occurred on Dec. 26.

4. There are about 500,000 earthquakes a year around the world, as detected by sensitive instruments. About 100,000 of those can be felt, and 100 or so cause damage each year. Each year the southern California area alone experiences about 10,000 earthquakes, most of them not felt by people.

5. The sun and moon cause tremors. It's long been known that they create tides in the planet's crust, very minor versions of ocean tides. Now researchers say the tug of the sun and moon on the San Andreas Fault stimulates tremors deep underground.

6. A city in Chile moved 10 feet in the massive 8.8 magnitude earthquake Feb. 27, 2010. The rip in Earth's crust shifted the city of Concepción that much to the west. The quake is also thought to have changed the planet's rotation slightly and shortened Earth's day.

7. There's no such thing as "earthquake weather." Statistically, there is an equal distribution of earthquakes in cold weather, hot weather, rainy weather, and so on, according to the U.S. Geological Survey. Scientists say there is no physical way that weather could