Tomatlan Earthquake: 5 Fast Facts You Need to Know

A magnitude 6.6 earthquake has struck near the town of Tomatlan, Mexico at about 6:30 a.m. local time.

Here’s what you need to know:

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1. Magnitude 6.6 Is a Large Earthquake

Earthquakes are measured by using the Richter magnitude scale, though earthquakes are often described by the approximate analogous nuclear blast. For example, a 6.0 magnitude earthquake is the equivalent of about 15 kilotons, the size of the bomb that was dropped on Hiroshima at the close of WWII.

As earthquakes get larger, the magnitudes scale up quickly, and a 6.6 magnitude earthquake is equivalent to 120 kilotons, or eight Hiroshimas. A 2010 earthquake measuring 6.6 on the Richter scale that struck Eureka, California, was felt as far away as Reno, Nevada.

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2. There Are Several Large Cities Nearby

The closest city to the epicenter of the earthquake is Tomatlan, about 131 miles away, though there are other large cities within close range.

Puerto Vallarta, a popular vacation destination, is only 164 miles away, and Mexico City, one of the largest cities in the world, home to almost 9 million people, is 504 miles away.

In 1985, a magnitude 8.1 earthquake struck near Mexico City wreaking a tremendous cause of damage and causing the deaths of as many as 40,000 people.

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3. The Pacific coast of Mexico is Prone to Earthquakes

According to the U.S. Geological survey, Mexico is located on top of three of the large tectonic plates:

Mexico is one of the world’s most seismically active regions. The relative motion of these crustal plates causes frequent earthquakes and occasional volcanic eruptions.

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4. Mexico Has Recorded 966 Earthquakes in the Past Year

Though most of them have been small, Earthquake Track lists 13 earthquakes in the past week in Mexico, greater than 1.5 magnitude. There have been 83 earthquakes over the course of the past month and 966 earthquakes in Mexico within the past year.

According to the U.S. Geological Survey, “Mexico has a long history of destructive earthquakes and volcanic eruptions:”

In September 1985, a magnitude 8.1 earthquake killed more than 9,500 people in Mexico City. In southern Mexico, Volcán de Colima and El Chichón erupted in 2005 and 1982, respectively. Paricutín volcano, west of Mexico City, began venting smoke in a cornfield in 1943; a decade later this new volcano had grown to a height of 424 meters. Popocatépetl and Ixtaccíhuatl volcanos (“smoking mountain” and “white lady”, respectively), southeast of Mexico City, occasionally vent gas that can be clearly seen from the City, a reminder that volcanic activity is ongoing.

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5. Seismologists Say There’s No Tsunami Risk

The offshore earthquake that hit near Tomatlan occurred at a depth of 22 meters, about 100 miles off the coast.

Nonetheless, NOAA lists no tsunami risk for the Pacific coast, and has issued no tsunami warning or watch.