U.S. ROUTE 395 is a geologic master class disguised as a road. It runs north from the arid outskirts of Los Angeles, carrying travelers up to Reno along the eastern flank of the Sierra Nevada. On the way, they pass the black cinder cones of Coso Volcanic Field and the eroded scars of a mighty 19th-century earthquake near Lone Pine. In winter, drivers might see steam rising from Hot Creek, where water boils up from an active supervolcano deep underground.
About an hour from the Nevada border, Mono Lake appears, with its bulbous and surreal mineral formations known as tufa towers. Even for someone with no particular interest in rocks, these are captivating, otherworldly sights. But for James Faulds, Nevada’s state geologist, they are something more — clues to a great tectonic mystery unfolding in the American West. If he’s right, all of this, from the wastes of the Mojave Desert to the night-lit casinos of Reno, will someday be beachfront property.
For more than a century, the San Andreas Fault has been considered the undisputed heavyweight champion of large-scale deformation in the West. It is here that the North American and Pacific Plates meet, jostling for position with often violent results. Eventually, the theory goes, the thin sliver of land between the fault and the ocean — from the southern tip of the Baja Peninsula to the Santa Cruz Mountains — will break off from the mainland and slide north, until LA drifts past San Francisco.