They are designed with this in mind, and certainly hold up better than oil pipelines, which also have to be engineered to withstand earthquakes. I expect it is

They are designed with this in mind, and certainly hold up better than oil pipelines, which also have to be engineered to withstand earthquakes. I expect it is unlikely for an earthquake itself to sever a cable, but knocking out power / knocking over a building that then destroys the cables landing site is possible, if rare.