Although the earthquake that struck the east coast on Tuesday was extraordinary, primarily due to its 5.9 magnitude, on the whole earthquakes are rather routing geologic events.
For example, the United States Geologic Survey (USGS) daily lists earthquake events around the world (including aftershocks) on its Web site. They limit the list to quakes in the U.S. with a magnitude greater than 2.5, according to the Richter scale; and quakes in foreign nations of at least magnitude 4.5.
Generally speaking, quakes below 2.5 are not even felt by the public. Quakes of magnitude of 4.5 or higher can cause damage. Also, it must also be kept in mind that the Richter scale is logarithmic, not linear. This means that a magnitude 5 earthquake would cause 10 times the amount of damages (level of shaking) as magnitude 4 – and also release 32 times the amount of energy. (The Japanese earthquake from March 2011 was magnitude 9.0).
In any case, according to the USGS site, on Tuesday, the day the earthquake struck the east coast of the U.S., there were at least 30 seismic actions around the world of at least magnitude 2.5. Some of these “events” were aftershocks of the Monday quake in Colorado, the biggest such tremor in 40 years in that region.
However, on that day, there were several other quakes around the globe that received scant media coverage, including: Eastern New Guinea (magnitude-5.2); Fiji (5.0); Northern Colombia (4.7); Hindu Kush, Afghanistan (4.8); Kashmir, India (5.1) and Hokkaido, Japan (4.8).
Similarly, on Wednesday, as of 2.45 p.m. (EDT), there were 24 quakes recorded, including a magnitude 3.5 tremor in the San Francisco Bay area. However, the biggest quake (one of magnitude-5.4) struck in the Norwegian sea – in addition to significant tremors and aftershocks in Kashmir, Fiji, Afghanistan, among other places.