San Francisco -- Rebuilding San Francisco after a major earthquake would change its human face, hastening gentrification and driving out poor and elderly residents, experts and city officials warn. Experts say there's a 62 percent chance a quake with a magnitude of 6.7 or higher will hit the San Francisco Bay area within several decades — or tomorrow. Thousands of homes would be rendered uninhabitable, displacing up to 300,000 residents, almost half the city's population, according to some projections. A major issue would be creating replacement housing for the poor in one of the nation's most expensive markets. About 16,000...
