GL102 Lecture Notes - Lecture 13: Divergent Boundary, Convergent Boundary, Oceanic Crust
Document Summary
Transform boundaries: transform boundaries are marked by shallow-focus earthquakes in a narrow zone for a single fault or in a broad zone for a group of parallel faults. First-motion studies of the quakes indicate strike-slip movement parallel to the faults: the name transform fault come from the facts that the displacement along the fault abruptly ends or transforms into another kind of displacement. The most common type of transform fault occurs along fracture zones and connects two divergent plate boundaries at the crest of the mid-oceanic ridge. The spreading motion at one ridge segment is transformed into the spreading motion at the other ridge segment by strike-slip movement along the transform fault. Not all transform faults connect two ridge segments. A transform fault can connect a ridge to a trench (a divergent boundary to a convergent boundary), or it can connect two trenches (two convergent boundaries). The offsets appear to be the result of irregularly shaped divergent boundaries.
