Scientists studying last month's earthquake in Christchurch say the shaking was exacerbated by a slapdown or trampoline effect that made the land under the city bounce up and down.
Scientists are just beginning to understand why the recent Canterbury earthquakes 'punched above their size', and their findings could change international scientific thinking about earthquakes. Alison Ballance talks with GNS seismologists Martin Reyners and Bill Fry to find out more.
GNS seismologists explain why the Darfield and Christchurch earthquakes were so damaging and 'punchy'