Triple Junction Analysis

Determine of the motion of the three plate boundaries at the triple junction, relative to the plates.  Determination of the triple junction motion first requires computing the motion of each pair of plates to determine the type of boundary.

A triple junction is stable only if the velocity lines for the three plate boundaries intersect in a single point. A stable triple junction will maintain it configuration over time, and it will almost certainly migrate with respect to the plates

If that point representing the triple junction's veclocity is not on the point representing the plate, the triple junction will be moving relative to that plate.  The triple junction cannot  be stationary with respect to all three plates, and in general will be migrate with respect to several of the plates.  A ridge-ridge-ridge triple junction will migrate with respect to all three plates.  The migration of the Mendocino triple junction north along the coast of North America between the Pacific and North American explains many of the salient features of the Cenozoic geologic history of California.


Last revision 2/27/2019