On its blog Wednesday afternoon, Twitter showed off some fascinating visualizations of how direct messages and tweets spiked shortly after an earthquake hit the Tohoku region of Japan in March.

“On Twitter, we saw a 500% increase in Tweets from Japan as people reached out to friends, family and loved ones in the moments after the March 2011 earthquake,” said the company on its blog.

This video shows the volume of @replies traveling into and out of Japan in a one-hour periods before and then after the earthquake. Pink replies are directed to users in Japan and from Japan are yellow.

This video shows retweets spread across the world, with original tweets in red and retweets in green:

Information design specialist Miguel Rios made the visualizations.

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