Macrozoning for earthquake engineering

Deformation at the collision edges of two vast moving tectonic plates, the Pacific and the Australian, has created and is now modifying our country.Dunedin and Auckland owe their existence to this slow violence no less than do Christchurch and Wellington.That sei smici ty varies from place to place has be en inferred from studies of land forms with some rough, possibly fortuitous, confirmation from the short hi storical record.No part of the country is safe, and for no part has there been any adequate study to quantify the risk.Neverthele ss, thi s tiny siiver of land has been'divided into five macrozones to which numbers have been attached indieating very significant differences in intuitively selected sei smic risk factors for de sign.