When is the Big One? Earthquakes, calamities and other portents

THE Philippines sits on the Pacific Ring of Fire, a belt of countries around the Pacific Ocean that is prone to earthquakes and volcanic eruptions. Underground, it is lined with many fault lines, fissures and cracks. Its tectonic plates jostle against each other a few times each year. And there is always talk of the Big One, like a dark cloud in the air.

On April 3, the Philippines' northern neighbor, Taiwan, was rocked by a magnitude 7.4 earthquake that was the island's most powerful in 25 years. It lasted for a minute, but it tilted buildings, killed at least nine people and set off tsunami warnings in China, Japan and the Philippines. More than 1,010 people were injured.