7 Hot Facts About the Pacific Ring of Fire

When the explorer Ferdinand Magellan visited Earth’s biggest ocean in 1520, he found the waters pleasantly calm. And that’s why — to this day — most people call it the Pacific Ocean, as “pacific” is a synonym for “peaceful.”

More than 15 countries are pierced by this geologically interesting area

MARK MANCINI

Oh, the irony. Magellan didn’t know it, but there’s a vast loop of volcanoes, trenches and seismically active places running through and around the Pacific. This would be the (in)famous “Ring of Fire.” About 24,900 miles (40,000 kilometers) long, it’s where most of the world’s earthquakes and volcanic events take place. Here’s a seven-part crash course on the region as a whole. Spoiler alert: It’s got nothing to do with that Johnny Cash love song. Unfortunately…

EXPLAINER: How glaciers can burst and send floods downstream

The floods that slammed into two hydroelectric plants and damaged villages in northern India were set off by a break on a Himalayan glacier upstream. Here’s a look at how glaciers and glacial lakes form and why they may sometimes break:

Glaciers are found on every continent except Australia and some are hundreds of thousands of years old. A large cluster of glaciers are in the Himalayas, which are part of India’s long northern border. Sunday’s disaster occurred in the western part of the Himalayas.

Glaciers are made of layers of compressed snow that move or “flow” due to gravity and the softness of ice relative to rock. A glacier’s “tongue” can extend hundreds of kilometers (miles) from its high-altitude origins, and the end, or “snout,” can advance or retreat based on snow accumulating or melting…