MOVEMENT OF the Indian tectonic plate northward at 40mm per year causes most earthquakes in the region, said Society for Earthquake & Civil Engineering Dynamics chairman, Zygi Lubkowski.
'The Indian plate is moving north and creating a compressional plate boundary (between it and the Eurasian plate).
'Along here is a series of thrust faults where this pressure creates steps in the ground, typically of 2m to 3m.
'Colleagues at Imperial College have estimated that in this case the fault line was approximately 100km long running from north to south, which explains why such a large area has been affected, ' Lubkowski said.
The quake's epicentre was 10km below ground and is considered a relatively shallow event. This means that damage is potentially greater as more energy is transferred to the surface.
'The acceleration in a shallow event is much higher and the separation time between the horizontal pressure wave and the slower moving surface wave is much shorter, making the impact more destructive, ' explained chairman of the IStructE's Earthquake Engineering Field Investigation Team (EEFIT), Gopal Madabhushi.