About 500,000 earthquakes occur each year – 100,000 of which are felt on the Earth’s surface. But how do earthquakes work? We explain. South Carolina was hit by several earthquakes on Wednesday, including the two strongest earthquakes to date in a “swarm” of earthquakes that shook the state this year. Two quakes measuring 3.5 on the Richter scale shook central South Carolina on Wednesday, according to the U.S. Geological Survey. A 3.4 magnitude earthquake shook the state over the weekend. The quakes were the strongest to hit the state for years, and at least one of Wednesday’s tremors could be felt near Charlotte, North Carolina, according to reports released by the United States Geological Survey. In a video released by the state Department of Emergency Management, geologist Wendy Bohon said more than 30 earthquakes have hit the state this year as part of a “swarm of earthquakes.” Such swarms are common in more seismic areas, but unusual in the South. The South Carolina swarm has been going on for more than half a year and included 7 earthquakes of more than 3 Richter, according to seismologist Lucy Jones. “Swarms occur in all seismic areas and earthquakes continue until they stop,” Jones wrote on Twitter. “This may not seem helpful, but knowing that this is normal can help.” The latest quake occurred near Eljin, South Carolina, according to the United States Geological Survey. The city is located about 20 miles northeast of Columbia, the state capital. “TOMORROW MAY HAPPEN”: Experts know disaster is approaching on the West Coast The last time a major earthquake shook the state was in 2014, according to historical data of the agency. The 3.5-magnitude quake was felt about 70 miles north along the state line near Charlotte, according to USGS reports. South Carolina has many fault systems and is “one of the most seismically active states on the East Coast,” the state’s Emergency Management Division wrote on Twitter. An 1886 earthquake in the Charleston area “is the largest earthquake in the southeastern United States and the most devastating, killing 60 people,” said an official earthquake guide. The quake was estimated at 7.3 on the Richter scale – similar to the dreaded “Big One” that is expected to devastate Southern California one day.
