towards the earthquake epicentre in the southwest. Small, but significant, co-seismic
jumps between 5 and 10 mm were detected even at stations more than 3000 km away from the earthquake epicentre. In the vertical direction, ground displacements in the near field (close to the earthquake epicentre), determined from various techniques, show a
characteristic pattern: a region of (co-seismic) uplift near the Sumatra trench and a region of subsidence away from it (Subarya et al., 2006). Evidence of 1500 mm uplift near the epicentre of the earthquake was shown in Sieh (2005) in the form of emerged coral reefs. In the far field the elastic dislocation slip model (Meltzner et al., 2006) predicts co-seismic subsidence that decreases when moving further away
from the Sumatra trench, where the earthquake epicentre is located.