Japan has over 1000 GPS stations permanently installed throughout the country, about one GPS station every 30 kilometers (18.6 miles). This movie shows the movement of the land in Japan from the magnitude 9.0 earthquake which took place near Honshu, Japan on March 11, 2011.
The red star east of the island marks the earthquake epicenter. During the earthquake, the east coast of Japan nearest the earthquake moved eastward approximately 4 meters (13 feet) and sank close to 1 meter (3.2 feet). These areas are shown in bright yellow on the movie. The arrows show the direction of movement of each GPS station. In some areas, strong shaking from the earthquake lasted five minutes and triggered a tsunami of more than 10 meters (33 feet) in height.
Researchers are working to use GPS data collected while an earthquake is happening to calculate the magnitude of the earthquake. By quickly calculating the magnitude of an earthquake, early warnings can be sent that can help save lives.