Earthquake Fault Trace Survey: Central Hawke’s Bay District.

Abstract

Parts of the Poukawa, Waipukurau and Tukituki Fault Zones in Central Hawke’s Bay District have been mapped in detail according to the Guidelines of the Ministry for the Environment’s “Planning for Development of Land on or Close to Active Faults”. Fault traces with associated Fault Avoidance Zones have been mapped to produce corridors surrounding the active fault traces at a scale suitable for the purposes of cadastral zoning, i.e. c. 1:5000. Particular attention has been paid to the urban areas of Otane, Waipawa and Waipukurau. Mapping of the Fault Avoidance Zones has been undertaken using a Geographic Information System (GIS) in conjunction with rectified aerial photographs, ortho-photographs and LiDAR imagery. Each of these media have a level of uncertainty for mapping. We found that a 5-m pixel Shaded Relief LiDAR image produced particularly accurate micro-topography of the mapping areas, allowing us to map fault features to a level of accuracy not possible with the other more traditional methods.