What Caused That Loud Boom in South Carolina?

Additional context from the article:

> About 5:30 p.m. on Thursday, the boom was heard throughout the central part of South Carolina, including the capital city, Columbia, and an area extending at least 40 or 50 miles east. The United States Geologic Survey said it was centered just about three and a half miles northeast of St. Andrews, in the Columbia metro area.

> There were no reports of damage or serious injury, but it left the region puzzled. Hundreds of residents described hearing the sudden, jarring noise, and a rumble that felt like an earthquake. Many expressed their alarm on social media: “It felt like a bomb just went off,” one person said, while another wrote, “It shook my room.”