Earthquakes often strike unexpectedly, raising questions about their origins. This intriguing video explores the possibility that recent seismic activity in North America may be influenced by earthquakes from decades, or even a century, ago. Researchers have started to uncover evidence suggesting that past geological events have lasting effects that continue to cause tremors today. Through analyzing historical seismic data, they are beginning to understand how these old earthquakes might still play a significant role in the seismic patterns we observe now.