Head of the Geofon Program of the German Research Center for Geosciences (GFZ) Winfried Hanka points to a seismogram of an earthquake in Indonesia in Potsdam, Germany, 11 April 2012. Sumatra in Indonesia was shocked by a severe earthquake and aftershock today. The earthquake reached values of 8.5 and 8.1 on the Richter Magnitude Scale. A Tsunami warning was issued for Sumatra. Photo: MAURIZIO GAMBARINI -ALLIANCE-INFOPHOTO