A boundary between plates where the relative motion is horizontal. The San Andreas fault is a transform boundary between the North America plate and the Pacific plate. The Blanco fracture zone ( Figure 12 ) is a transform boundary between the Juan de Fuca and the Pacific plates.

A plate boundary where the plates slip past eachother as a the San Andreas Fault in California.

a boundary between two crustal plates formed as they slide past one another in opposite directions without converging (see Convergence) or diverging (see Divergence).

in plate tectonics, a boundary between tow plates that are sliding past one another

plate boundary where two plates are sliding past each other.

In plate tectonics, a transform boundary (also known as transform fault boundary, transform plate boundary, transform plate margin, slip boundary or conservative plate boundary) is said to occur when tectonic plates slide and grind against each other along a transform fault. The relative motion of such plates is horizontal in either sinistral or dextral direction.