the size of the quake
, but also how near it is to the surface, the density of the population near its epicentre, as well as whether there are any heavily urbanised areas nearby. These all indicate a higher death toll - and were all features of the Haiti quake.
The devastating earthquakes that hit China on 12 May 2008, Italy on 6 April 2009 and Haiti one month ago all measured above 6.0 and took many lives. But why was the human cost so much greater for Haiti?
"Corruption
One of the problems in Port-au-Prince is the lack of space, he adds, as well as a constantly shifting and mobile population. The task now for such organisations is to help the people of Haiti get back on their feet, given the inevitable crippling economic cost of such a quake.