ABSTRACT
In the late 1970s and 1980s, the plate tectonics "revolution" took an interesting turn. It became old-hat for the land geologists. Dan McKenzie and Jason Morgan first described this geometric relationship in their 1969 paper about triple junctions. The relationship just described is very useful for establishing the timing of events in western North America. Since the San Andreas Fault system forms the boundary between the Pacific and North American plates, it could not have originated until those two plates came into contact. Various grand schemes to drill through the entire oceanic crust and into the mantle had been around since the Mohole project of the 1950s. The San Andreas history is quite unusual in that the oceanic and continental realms are so completely, intricately intertangled. Meanwhile, on the global scale, the marine geophysical group at Lamont was busy interpreting the world.
