Simon Winchester is the acclaimed author of many books, most recently Atlantic: Great Sea Battles, Heroic Discoveries, Titanic Storms, and a Vast Ocean of a Million Stories.

The earthquakes yesterday scared people along the East Coast, but Simon Winchester warns that the truly terrifying earthquake may strike the Midwest.

With a column I wrote recently, I seem to have helped reignite a debate that enrages many geophysicists: Do quakes occur in clusters—and if so, what does Japan's portend for the U.S.? The answer remains far from clear.