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(CNN)An earthquake with a preliminary magnitude of 7.8 struck off the coast of Alaska early Wednesday morning.
The earthquake was centered 60 miles, or 98 kilometers, south-southeast, of Perryville, Alaska, according to the US Geological Survey. The quake is considered shallow at about six miles, or 10 kilometers, deep.
"Anything below 70 kilometers is considered a shallow quake," CNN meteorologist Allison Chinchar said. "That's important, because shallow earthquakes often cause the most damage, compared to the ones that are deeper, regardless of the strength."
A tsunami warning has been issued following the earthquake, according to the National Oceanic and Atmospheric Administration. The warning is in effect for south Alaska and the Alaska peninsula -- Pacific coasts from Kennedy Entrance, Alaska (40 miles southwest of Homer) to Unimak Pass, Alaska, according to the Tsunami Warning Center.
Earthquakes are more likely to develop into tsunamis if they are high in magnitude, are shallow, and are thrust earthquakes rather than strike slip earthquakes, according to the USGS. Quakes between magnitudes 7.6 to 7.8 have the potential to produce destructive tsunamis.
