transform margin

In plate tectonics, a boundary between two lithospheric plates in which the plates move past each other rather than towards or away from one another. Transform boundaries are characterized by large strike-slip faults called transform faults, and powerful and destructive earthquakes.

Transform margins are named as such because they act as a connection, or ‘transform’, between two other types of margins. The boundary between two plates differs from place to place: some segments are convergent margins, some divergent margins, and some transform. Transforms link convergent with divergent segments, and similar segments with each other. The most famous example is the San Andreas fault, which marks the boundary between the North American and Pacific plate.