This story was literally cooked up over a bowl of mulligatawny soup.
Back before she married Lester Del Rey and became one of the most innovative and successful book editors in the history of science fiction, Judy-Lynn Benjamin was managing editor of Galaxy magazine. (Or, as Robert Blocka slyly put it, she was "the man-aging editor.") Judy-Lynn and I had lunch in one of Manhattan's Indian restaurants and started talking about the dire news media fears of the Big One: an earthquake along the San Andreas Fault that would knock California into the Pacific Ocean.
I muttered a "what if" kind of idea. Judy-Lynn laughed heartily and told me to write the story for Galaxy.
But the joke was on me. When I sent the story in, Galaxy's editor in chief, knowing me as the author of scientifically accurate stories, demanded to know the scientific basis behind my story.
I sold the story elsewhere, much to Judy-Lynn's chagrin. And mine.