Twitter is a remarkable tool to analyze information diffusion, and investigate social patterns and trends. In June 2011, Abdur Chowdhury and his team at Twitter posted a few visualization experiments covering the volume and worldwide scale of Twitter messages during the devastating earthquake in Japan on March 11.
As they stated on the original post: "During major events, people use Twitter to share news and thoughts with friends, family and followers around the world. Messages originating in one place are quickly spread across the globe through Retweets, @replies and Direct Messages. We see this behavior during everything from sporting events like the World Cup to widely-televised news events like the royal wedding, and also in the face of major disasters like the March 11 earthquake in Japan, where the volume of Tweets sent per second spiked to more than 5,000 TPS five separate times after the quake and ensuing tsunami."
To better understand this diffusion process, Abdur and his team created two video clips. The first image is from a clip showing the volume of @replies traveling into and out of Japan in a one-hour period just before and then after the earthquake. Replies directed to users in Japan are shown in pink; messages directed at others from Japan are shown in yellow.
The second one is from a clip displaying worldwide retweets of Tweets originating in Japan for one hour after the earthquake. Senders' original Tweets are shown in pink; Tweets retweeted by their followers in the hour after the event are displayed in green.