A pothole in a road surface, showing tyre marks where a vehicle has driven through the hole. The photographer comments, "After the earthquake in Christchurch in February 2011 burst underground pipes and liquefaction caused unseen hollows under the road surfaces. Occasionally after all the rest have been exposed by traffic someone would find 'discover' a new one".
Spray paint on the footpath to mark out the uneven surface.
A street sign and road cone near the Avon River saying "Uneven Surface".
Spray painted marks on the footpath outside the Casino indicating cracks and uneven surfaces.
The previously unknown Greendale Fault ruptured to the ground surface, causing up to 5 metres horizontal and 1 metre vertical permanent offset of the ground, during the September 2010 Darfield (Canterbury) earthquake. Environment Canterbury commissioned GNS Science, with help from the University of Canterbury, to define a fault avoidance zone and to estimate the fault recurrence interval. There is little evidence for past movement on the fault in the past 16,000 years. However, because of the uncertainties involved, a conservative approach was taken and the fault has been categorised as a Recurrence Interval Class IV fault (a recurrence interval of between 5,000 and 10,000 years). A PhD study by a University of Canterbury student will work towards refining the Recurrence Interval Class over the next three years. Taking a risk-based approach, the Ministry for the Environment Active Fault Guidelines recommend that normal residential development be allowed within the fault avoidance zone for faults of this Recurrence Interval Class, but recommends restrictions for larger community buildings or facilities with post-disaster functions. The report is assisting Selwyn District Council in granting consents for rebuilding houses on or near the Greendale Fault that were damaged by permanent distortion of the ground due to the fault rupture in the September 2010 earthquake. The report provides specific recommendations for building on or close to the Greendale Fault, which are being implemented by Selwyn District Council. See Object Overview for background and usage information.
A damaged house with cracks down the wall sits on an uneven surface.
Two road cones mark out an uneven surface on the road. The hole is filled with water.
A view down the Avon River in the city centre. A street sign marks out an uneven surface further down the street.
Dried liquefaction silt in North New Brighton. The photographer comments, "Here you can see the very fine surface layer of liquefaction starting to shrink, crack and then curl up on itself".
Road damage and liquefaction in a residential street. The photographer comments, "A great gouge in the road caused by liquefaction undermining the road surface and a car driving over it. This was the earthquake in Christchurch, New Zealand on 22 February 2011".
Liquefaction in North New Brighton. The photographer comments, "This is the liquid part of liquefaction left when the heavier sand content has dropped down. After the double quake in Christchurch local to me I found these strange lines of bubbles on the surface".