For the first time, scientists have produced a computer image showing huge sections of California rising and sinking around the San Andreas fault. The vertical movement is the result of seismic strain that will be ultimately released in a large earthquake. The San Andreas fault is California’s longest earthquake fault, and one of the state’s most dangerous. Scientists have long expected that parts of California are rising — and other parts sinking — around the fault in a way that is ongoing, very subtle and extremely slow. Such vertical movement makes a lot of sense. California sits on the border of two gigantic tectonic plates — the Pacific and North American — that are constantly grinding past each other. 'Seismic strain': Land around the San Andreas fault is rising and sinking, new earthquake research shows Love ya'll.