The road and footpath are covered in silt from liquefaction in a residential area.
The road and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
The road, driveway and footpath are covered in silt from liquefaction in a residential area.
Silt from liquefaction outside the Merivale Mall. Some sections of the street have been cordoned off.
A digitally manipulated image of printer's type, spelling out "Safe Dust". The photographer comments, "After the September 2010 Christchurch earthquake liquefaction poured out of the ground mostly in the East of Christchurch. This silt, which was a form of sand was declared safe and would not harm gardens if it was spread around in moderation. After the February 2011 quake as a result of even more liquefaction and the sewers being ruptured, the liquefaction was declared as toxic. People clearing it up should wear a mask, boots and gloves especially when it had dried up and become dusty. This just so happens to be the words found on an old printing press".
A van partially submerged in liquefaction. The photographer comments, "A van that unluckily drove into a hole caused by the terrible liquefaction on Beach Road, North New Brighton during the Christchurch earthquake".
A van partially submerged in liquefaction. The photographer comments, "A van that unluckily drove into a hole caused by the terrible liquefaction on Beach Road, North New Brighton during the Christchurch earthquake".
Photograph captioned by Fairfax, "Christchurch Earthquake. Damage in Dallington. Cardboard sign on liquefaction silt pile reads 'Free'".
The last pile of liquefied silt to be cleaned up, from our lawn.
Grass growing through liquefaction silt in Avondale. The photographer comments, "Although this grass seems to be growing on the liquefaction created by the earthquakes in Christchurch, New Zealand, they are actually only growing through it. Nothing seems to grow even though seeds will sprout almost anywhere else. The seeds are growing in the soil which got covered up by the liquefaction. If liquefaction gets mixed with even a little soil then nature can get a foothold".
Liquefaction and flooding in Waitaki Street, Bexley. The photographer comments, "Waitaki Street a week after the Christchurch Earthquake. Because of the damage to the drains and liquefaction in the area the streets are not drying out".
Silt from liquefaction outside the Merivale Mall. A pile of carpet pieces sit in front of the mall.
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".
A digitally manipulated photograph of the bottom of Victoria Lake in Hagley Park. The photographer comments, "After the Christchurch earthquake in February 2011, Victoria Lake suffered some cracking which broke the previous clay seal. The lake has now been excavated so that the new clay seal can be spread out and flattened ready to be filled again with water. The red pile is the clay and in the background is the grey silt or liquefaction that spewed into the lake from cracks in the lake bed".
Workers inspect a broken sewerage line in New Brighton. The photographer comments, "After the Christchurch earthquake on 23 December 2011 the sewer pipe got badly damaged at New Brighton and was leaking into the Avon River. I think the guy was worried about the fast flow causing him to fill his boots rather than the depth".
The Holiday Inn On Avon has been fenced off, and silt from liquefaction still remains on the surrounding area.
Damage to a block of flats, with silt from liquefaction around the footpath, and road cones blocking the driveway.
Damage to a block of flats, with silt from liquefaction around the footpath, and road cones blocking the driveway.
Dried liquefaction silt in North New Brighton. The photographer comments, "This is the result of liquefaction which spewed out after the double earthquake in Christchurch. Having flowed into a shallow depression that was deep enough for a fair quantity of the silty liquid to settle and separate: the heavy sand below and a talcum powder like substance on top. Some of these are so delicate that a mouse crossing them would probably crack them. Here the sun has dried them out and they have contracted and curled up towards their centres".
Damage down a residential street. The road is covered in silt from liquefaction and a portaloo can be seen in the background.
The land and houses close to the Avon River have been badly damaged. Many road and footpaths are covered in silt from liquefaction.
The land and houses close to the Avon River have been badly damaged. Many road and footpaths are covered in silt from liquefaction.
The road and footpath are covered in silt from liquefaction in a residential area. A portaloo stands at the front of the house.
On February 22, 2011, a magnitude Mw 6.2 earthquake affected the Canterbury region, New Zealand, resulting in many fatalities. Liquefaction occurred across many areas, visible on the surface as ‘‘sand volcanoes’’, blisters and subsidence, causing significant damage to buildings, land and infrastructure. Liquefaction occurred at a number of sites across the Christchurch Boys High School sports grounds; one area in particular contained a piston ground failure and an adjacent silt volcano. Here, as part of a class project, we apply near-surface geophysics to image these two liquefaction features and determine whether they share a subsurface connection. Hand auger results enable correlation of the geophysical responses with the subsurface stratigraphy. The survey results suggest that there is a subsurface link, likely via a paleo-stream channel. The anomalous responses of the horizontal loop electromagnetic survey and electrical resistivity imaging highlight the disruption of the subsurface electrical properties beneath and between the two liquefaction features. The vertical magnetic gradient may also show a subtle anomalous response in this area, however the results are inconclusive. The ground penetrating radar survey shows disruption of the subsurface stratigraphy beneath the liquefaction features, in particular sediment mounding beneath the silt ejection (‘‘silt volcano’’) and stratigraphic disruption beneath the piston failure. The results indicate how near-surface geophysics allow the characteristics of liquefaction in the subsurface to be better understood, which could aid remediation work following liquefaction-induced land damage and guide interpretation of geophysical surveys of paleoliquefaction features.