The Earths Crust is split into sections called tectonic plates, when it happens magma rushes up to fill the Gap which is creating brand new crust Where a divergent boundary crosses the land, the rift valleys which form are typically 30 to 50 kilometers wide. Examples include the East Africa rift in Kenya and Ethiopia, and the Rio Grande rift in New Mexico.
" In plate tectonics, a convergent boundary, also known as a destructive plate boundary (because of subduction), is an actively deforming region where two (or more) tectonic plates or fragments of the lithosphere move toward one another and collide. " " One of the converging plates must be an oceanic plate to form a subduction zone. When two continental plates collide mountain ranges like the Himalayas form. "
" A transform fault or transform boundary, is a type of fault whose relative motion is predominantly horizontal, in either a sinistral or dextral direction " " The San Andreas Fault is a transform boundary, which means the two plates are sliding alongside each other. The western half of California is moving north because it is part of the Pacific Plate, and the eastern half of California is moving south because it is part of the North American Plate. "