California has a relatively high number of earthquakes due to its position on both the Pacific and North American Plates. These plates are in constant motion, and earthquakes occur when their sides slip against one another suddenly.Know More
The San Andreas Fault is the boundary line between the two plates, and it runs roughly from north to south along much of the length of the state. There are hundreds of other smaller faults in the state, with about 200 of them considered potentially dangerous due to their slip rates. An estimated 70 percent of the state's population lives within 30 miles of a fault, where noticeable levels of ground shaking can occur.
California generally experiences two or three, large-scale, earthquakes per year of a magnitude of 5.5 or greater, the level at which moderate damage to structures can occur. Small earthquakes occur on an almost daily basis throughout the state, but most are too small to be felt. The state experienced over 2,900 earthquakes in total in 2014.
Though California is one of the regions of the world most prone to earthquakes, it does not have the most or the largest quakes. Within the United States, Alaska has both more and larger earthquakes.Learn more about Earthquakes
Earthquakes happen daily across the United States, though they vary in magnitude. For instance, the United States had 3,836 earthquakes in 2012, but only five of them were above six on the Richter scale, and none of them exceeded seven.Full Answer >
Earthquakes occur most often along the edges of oceanic and continental plates. Oceanic plates are the large pieces of the Earth's crust that are located beneath the oceans. Continental plates hold the Earth's large land masses.Full Answer >
According to the United States Geological Survey, several million earthquakes occur worldwide each year. It is difficult to refine this estimation to an exact number because many earthquakes go undetected, either because they occur in locations that are uninhabited or barely inhabited, or they are too small in magnitude to be detected by seismographs or other forms of detection.Full Answer >
As of 2014, estimates suggest that over 500,000 earthquakes occur each year, and 100,000 of these are strong enough to be felt by humans. Since 1900, there has been a global average of 18 major earthquakes, and one giant earthquake, each year.Full Answer >