The magnitude 8.8 quake is believed to be the joint sixth-largest on record, though only minor injuries near the epicenter have been reported.

One of the most powerful earthquakes ever recorded has sent a tsunami crashing into a Russian port and smaller waves barreling across the Pacific to the Americas and south to New Zealand.

Russia’s magnitude 8.8 earthquake spawned serious tsunami warnings, but waves have been moderate so far. Here’s the geological reason why