New research published in the Journal of Geophysical Research: Solid Earth has found that powerful earthquakes that occurred in the United States almost 200 years ago may still be causing aftershocks. Specifically, aftershocks are still occurring near the Missouri-Kentucky border and in Charleston, South Carolina. The aftershocks from these antiquated earthquakes present a significant challenge in determining their impact and future disaster risk. There is disagreement on determining whether aftershocks are still occurring, with some seismologists believing they are, while others do not. The fact that there were no seismographs at the time of these earthquakes adds to the uncertainty and difficulty in making definitive conclusions. Ultimately, the study highlights the challenge of understanding the nature of seismic activities in dormant area and regions without a evolutionary access to a seismologically active area.