As we drove across Southern California yesterday, my focus was on the traffic and the scenery. I knew but did not consider the fact that we were leaving North America.
Of course, we did not depart the Continent but we did leave the North American Plate. As we descended through Cajon Pass on Interstate 15, we crossed the San Andreas Fault and changed tectonic plates. Indeed, Greater Los Angeles and San Diego are on the Pacific Plate, destined to break away from the North American Continent in the future.
During our brief human lives, we witness hints of tectonic activity, usually in the form of earthquakes and volcanism. But, except for those who live in southern and central California, it is not everyday (if ever) that we Americans leave our home plate.
