Overnight, the U.S. Geological Service measured an 8.1 magnitude earthquake that hit Mexico near the southern state Chiapas. It’s the strongest earthquake the country has seen in 85 years.
The Pacific Tsunami Warning Center confirmed tsunami waves measuring three feet off the coast of Mexico following the earthquake, along with magnitude 5.0 aftershocks.
According to Mexico’s National Seismological Service, which reported the earthquake at an 8.2 magnitude, the last earthquake of this magnitude hit the country on June 3, 1932, and left 400 people dead.
As of Friday morning, dozens of deaths had been reported, but the country remains on watch for continued threats. An automated system run by the U.S. Geological Survey, called PAGER, estimates damage from earthquakes based on the number of people living in affected regions and the scale of the region’s development. For Mexico’s earthquake, it estimated that as many as 1,000 people and a billion U.S. dollars could be lost as a combined result of tremors, tsunamis, and landslides.
More tsunami waves are expected to hit, and in farther-flung regions. Sudden displacement of ocean water from disasters such as earthquakes, volcanic eruptions, landslides, and meteorite strikes are capable of triggering waves that travel thousands of miles. To prepare, the National Weather Service’s Tsunami Warning System has issued warnings for regions in Central and South America, as well as the southern Pacific.
Chiapas is no stranger to quakes, as one of the most active seismic areas in Mexico. It sits at the convergence of the Cocos Plate, which is being shoved under the North American Plate.
The plates finally converged after years of motion, releasing a tremendous amount of energy in one quake, the president of the Geological Society of Washington, Callan Bentley, explained in a blog post on the American Geophysical Union’s website. Nearby volcanoes are formed from this area where one plate dives beneath another, called a subduction zone.
“The major earthquake that occurred last night was not a unique or one-off event. The area is known to have lots and lots of earthquakes over its long history of human habitation,” wrote Bentley.
Mexico’s military has been mobilized to help those in need, according to CNN. Electricity has returned to almost three quarters of the million homes that lost power overnight, but damage to buildings along the coast has been more devastating.
The region is expected to know the full extent of the damage as rescue efforts continue throughout the weekend.