Recording the Tsunami Quake's Motion    

              Sumatra - Andaman Islands Earthquake - December 26, 2004
          Seismograms Recorded by the Global Seismographic Network (GSN)


The seismogram to the left shows how quickly each of the GSN stations recorded ground motion from the December 26, 2004 earthquake.

Each colored line represents one station. The recordings indicate when each of the surface (R1, R2, R3, and R4) waves arrived. The stations located closest to the earthquake's epicenter recorded the seismic waves first.

Can you tell:





Image courtesy of USGS & Rick Aster, UNMT, New Mexico