What is the term for fault displacement that occurs over a time span of days to months without an accompanying earthquake?

The term that describes fault displacement occurring over days to months without an accompanying earthquake is known as a slow earthquake. This phenomenon occurs when stress is released along a fault plane through a slow and continuous movement rather than sudden release, which is typical in traditional earthquakes.

Slow earthquakes are commonly associated with subduction zones or fault systems where frictional forces allow for gradual displacement. This gradual motion can be detected by sensitive geodetic instruments, but it does not produce the intense ground shaking associated with conventional earthquakes. By contrast, terms like tectonic creep refer to continuous, minute displacements over long periods, but it is not typically defined by the timeframe of days to months combined with notable, detectable dislocation.

The understanding of these terms is critical in the field of geology and seismology, particularly for seismic hazard assessments and understanding the behavior of fault systems.