A 7.8 magnitude earthquake struck southern Turkey and Syria on Monday night in what's being recorded as the countries' worst natural disaster in recent memory — a stark reminder of the devastating tolls of strong earthquakes when regions are underprepared.
The U.S. is also prone to earthquakes of large magnitudes, particularly along the west coast, since there are many faults — put simply, a fracture between two very large rocks — in the country, Alex Hatem, a research geologist at the United States Geological Survey, told Insider.
"We're always monitoring the seismic network, called the Global Seismic Network," Hatem said. "So of course, that includes the United States as well as every other place on Earth. And we know in the U.S. that there are several places where we could have an earthquake this big."
Fault lines and studying the history of earthquakes can provide geologists and seismologists with a clue into where the next major earthquake might occur.
Turkey, for example, sits on the nexus of several large and small tectonic plates, making the country a highly seismically active region, John Louie, a geophysics professor at the University of Nevada, Reno, told Insider. The last time Turkey experienced an earthquake this large was in 1939, which left nearly 33,000 people dead.
The fault lines and a combination of a populous area, outdated building practices, and a yearslong civil war in Syria that hobbled the region's infrastructure left the two countries in a particularly vulnerable position.
"It just hit one of the worst prepared areas within Turkey and, of course, the war zone in Syria," Louie said. "There's no way to be prepared there, so it really is a terrible catastrophe."
There's no standard measurement of what makes an earthquake the "Big One," but there are several US states that can experience a shake at the magnitude of Turkey's earthquake.
Here are where the biggest earthquakes in the US can occur, and what you can do to prepare for them.