How can scientists tell what happen to the fault has not move for many years?

Scientists can assess inactive faults by studying geological features, such as offset landforms or sediment layers, which provide clues about past movements. They also use techniques like radiocarbon dating to determine the age of materials near the fault, helping to establish a timeline of activity. Additionally, paleoseismic studies involve excavating trenches along the fault to identify and date past earthquake events, revealing patterns of movement over time. This combined evidence helps scientists infer the fault's history and potential future behavior.