Nature & Environment

Earthquakes Today: Two Strike North America, California and Canada Hit

Kathleen Lees
First Posted: May 17, 2013 11:31 AM EDT

Two earthquakes hit the continent of North America in the last 24 hours, according to various reports.

An earthquake in Canada reported a 5.1-magnitude that struck just west of Ottawa but was felt as far away as Toronto. The federal agency that monitors earthquakes even revised its original report regarding the earthquake, saying it registered a 5.1-magnituted temblor with an epicenter located about 21 kilometers (13 miles) northeast of Shawville, Quebec, or about an hour's drive outside of Ottawa.  

The original report said a 4.8-magnitude quake was centered near the town of Braeside, Ontario, according to The Washington Post.

Yet, last night, another earthquake was reported just one mile from Niland California, according to the U.S. Geological Survey. The tremor occurred at 9:38 p.m.

According to the USGS, the epicenter was 16 miles from Brawley,  26 miles from Imperial, 29 miles from El Centro and 200 miles from Phoenix.

In the last ten days, there has been one earthquake magnitude 3.0 and greater centered nearby.

The device used to measure the severity of the earthquakes is commonly referred to as the Richter Scale, which was developed in 1935 by Charles F. Richter of the California Institute of Technology as a mathematical device to compare the size of earthquakes. The magnitude of an earthquake is determined from the logarithm of the amplitude of waves recorded by seismographs. Adjustments are included for the variation in the distance between the various seismographs and the epicenter of the earthquakes.

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