Definitions for "Seismic gap"
a zone along a tectonically active area where no earthquakes have occurred recently, but it is known that elastic strain is building in the rocks
An area in an earthquake-prone region where there is a below-average release of seismic energy.
a locked fault segment that has not experienced seismic activity for a long time. Because stress tends to accumulate in seismic gaps, they often become the sites of major earthquakes.