In Cecil Adams' column "The Straight Dope," which has appeared in alternative newspapers since 1973, he answered the following letter:
"When will California fall into the sea?" "It all depends on what you mean by 'fall into the sea,' " he wrote. "If you mean 'when will California break off the continent and sink to the ocean floor,' the answer is 'never.' The sea, you see, is only about two miles deep. California is about 20 miles thick.
"Perhaps you mean 'when will there be a major earthquake?' (An earthquake centered at the San Andreas Fault could involve a lot of vertical slip, which could conceivably put some California coastline under water.) In that case the answer is 'any day now, maybe.' Some geologists believe that the strain built up around the San Andreas Fault is already reaching the level of the great San Francisco earthquake of 1906. Others say the big day could be 100 years away.
"If you simply mean 'when will California slide away to oblivion?' the answer is about 50 million years. The Pacific 'plate,' which carries the western sliver of California, is sliding past North America at the dizzy rate of about two inches per year. Someday, Los Angeles will slide under the earth's crust near the Aleutian Islands, but this is not time to worry about it."
"The difference between Los Angeles and yogurt is that yogurt has an active, living culture."