Fault finding


“Stable” zones of the earth’s crust might not be so stable. These zones are more likely to cause massive earthquakes. It was thought that “stable” zones, where fault segments of the crust slip slowly, act as barriers to earthquakes and fast-slipping faults trigger them.

But it has now been found that the stable segments behave differently when a quake rupture penetrates them. Instead of arresting the rupture as expected, they can actually join in and make the quake larger.

This is how the magnitude 9.0 earthquake might have occurred in Japan in 2011, triggering the devastating tsunami. The finding can help identify earthquake-prone regions better.


Down to Earth January , 2013