This paper presents a summary of land damage observed in the Port Hills of Christchurch, New Zealand, following the earthquake sequence of 4 September 2010, in particular the land damage associated with a period of high seismic activity which commenced in February 2011. The earthquakes that occurred in this period have been collectively termed the Canterbury Earthquake Sequence (CES), consisting of four main earthquakes causing land damage in the Port Hills and some 20 significant aftershocks.
In New Zealand, the Earthquake Commission (EQC) administers and assesses claims made under the Earthquake Commission Act 1993 for residential land damage from earthquakes, (and other events included in the Act).
During the initial steps in property land damage mapping and assessment in the Port Hills for the EQC, it became apparent that in some areas, land deformation and movement observed on individual properties may have been the result of a mechanism that extended across many adjoining properties. Ultimately 22 such areas were identified to EQC and the observations made in those 22 areas form the basis of this paper.