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Images, UC QuakeStudies

Photograph captioned by Fairfax, "Christchurch Earthquake. A massive 7.4 magnitude earthquake has hit Christchurch and the wider South Island, causing widespread damage, two serious injuries and power cuts to most of the city. Marsha Witehira had the bricks from the wall of her house fall onto her bed where she was sleeping. Both sides of her house have collapsed. Witehira (R) is comforted by a friend".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "City Care workers. From left, Donny Haenga, Mafutga and David Henry enjoying a BBQ put on by City Care for their staff. The trio, from Wellington have work over 100 hours between them since Tuesday when they arrived. 35 specialists from Tauranga, Wellington, Dunedin and Timaru have joined the Christchurch staff with trucks and equipment from around NZ to help with the quake repairs".

Images, UC QuakeStudies

A black and white photograph of a sign reading "A tidy standard of dress is required." In the foreground is a pile of building rubble. The photographer comments, "I reversed this picture in the interests of my followers as it was harder to read the right way round. The wrecking crew did not wear ties, but they did look neat in their orange vests".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Christchurch CBD was 'yarn-bombed' during the weekend using yarn and fabric pieces to brighten public areas and earthquake-affected spaces. Visitor Ann Rees and her husband Bernard from South Wales said when looking at the yarn-bombed busts at the Arts Centre (from left: Diana Isaac, Elisie Locke, Charles Luney and Margaret Mahy) that it didn't appear like the work of vandals, but looked quite homely and warm".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Christchurch CBD was 'yarn-bombed' during the weekend using yarn and fabric pieces to brighten public areas and earthquake-affected spaces. Visitor Ann Rees and her husband Bernard from South Wales said when looking at the yarn-bombed busts at the Arts Centre (from left: Diana Isaac, Elisie Locke, Charles Luney and Margaret Mahy) that it didn't appear like the work of vandals, but looked quite homely and warm".

Images, UC QuakeStudies

A digitally manipulated image of a statue of the Virgin Mary in a broken window of the Cathedral of the Blessed Sacrament. The photographer comments, "Before the February 2011 earthquake the statue above was facing into the Cathedral looking down a corridor, but after it had turned 180 degrees to point towards the window. The statue of Mary turning like this gave a sign of hope for the people of Christchurch. It was amongst one of the most photographed things after the earthquake until it was removed".

Images, UC QuakeStudies

A digitally manipulated photograph of the Ozone Hotel's sign, leaning against a cordon fence. The photographer comments, "This sign was all that remained after the demolition of the historical Ozone Hotel, which was damaged in the Christchurch earthquakes. The sign disappeared so hopefully it will reappear at a later date in a museum. The bits of blue were the painted bricks of the hotel, which made it really stand out".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Invercargill Fire Station fire fighters who recently went to help in Christchurch for the Canterbury Earthquake cleanup. The National Boss presented the fire fighters with a Certificate of Commendation on Tuesday night. Invercargill firefighters Cameron McLachlan, Pete Scarlet, Dennis Hika, Chris Hamilton, Aaron Ramsay, National Commander Mike Hall, John Gilder, Ron Fetolofai (absent Murray Milne-Maresca) presented a certificate of commendation for their service during the Christchurch earthquake by national commander Mike Hall yesterday".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Damage to St. Mary's Anglican Church Timaru resulting from 7.1 Magnitude Earthquake centred near Darfield. (L to R on ground): Archdeacon Andrew Starky; Vicar Indrea Alexander and Concillor Ray Bennett watch as Craig Perkins and Kevin Deam are hoisted by crane to remove damaged spires from the church tower. (L to R): Builder Kevin Deam and St. Mary's parishioner Craig Perkins inspect a damaged spire on the church tower".

Images, UC QuakeStudies

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".

Images, UC QuakeStudies

A digitally manipulated photograph of twisted reinforcing rods amongst the rubble from the demolition of QEII. The photographer comments, "These rarely seen worms live in the pressurised earth under the foundations of buildings. They need a damp soil and be under at least 100 pounds of pressure per square inch. After the destructive force of an earthquake they swiftly rise to the surface through gaps in the rubble. Unfortunately they quickly die and then crystallise as hard as iron in the dry low pressure air".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Teeing off: Storeman Wayne Smith at the 12th hole of the Contact Wairakei Charity Golf Tournament for the Canterbury Earthquake Relief Fund. Held earlier this month, the tournament raised more than $8000 for the Canterbury Earthquake Relief Fund. In total more than $30,000 was raised for three charities at this year's annual tournament held at the Taupo Golf Club. As well as the $8200 raised for the Canterbury Earthquake Recovery Fund, two local charities Taupo Big Brother Big Sister and the Taupo Therapy Centre, each received $11,000 each from this year's fundraising effort".

Images, UC QuakeStudies

Photograph captioned by Fairfax, "Teddy time: A Whanganui man has sent dozens of teddy bears to Rangiora to be distributed to children affected by the Canterbury earthquake. Ted Cheriton sent the teddies to National MP Kate Wilkinson's office to be distributed. Ms Wilkinson said it was a fantastic gesture. 'I am sure they will be welcome in Kaiapoi and beach settlements where damage from the earthquake has severely affected many families', she said. 'Hopefully these teddies will bring a smile to some young children and cheer them up in what has been a very trying and traumatic time'".

Research papers, University of Canterbury Library

This paper describes the performance of (or damage to) ceilings in buildings during the 22nd February 2011 Christchurch earthquake and the subsequent aftershocks. In buildings that suffered severe structural damage, ceilings and other non-structural components (rather expectedly) failed, but even in buildings with little damage to their structural systems, ceilings were found to be severely damaged. The extent of ceiling damage, where the ceilings were subject to severe shaking, depended on the type of the ceiling system, the size and weight of the ceilings and the interaction of ceilings with other elements. The varieties and extent of observed ceiling damage are discussed in this paper with the help of photographs taken after the earthquake.

Articles, UC QuakeStudies

A photograph captioned, "I miss living here, right by the river. I'd been there for quite a long time, 12 years or so. I realize now I took it for granted a bit. I used to get a bit bored with having a big old house that was cold, difficult to clean, and perhaps hard to keep warm. But now, when I go back there, I miss living in a big house by the river with an open fire and a big lounge and everything. I had the park there on the other side of the river. And there was a little bridge down there where you could walk over to it. There was actually a circuit you could do, up to the New Brighton Bridge and back. Yeah, it was beautiful".

Images, Alexander Turnbull Library

In a series of five out of six caricatures Christchurch Mayor Bob Parker shows photographs of himself helping people hurt by the 4th September earthquake and helping Christchurch after the earthquake. In the sixth caricature he disingenuously smirks and says that he has been so busy helping Christchurch that he forgot about the Mayoral election; he then affects a philosophical stance about his chances. Refers to the advantage that the earthquake of 4th September has given the incumbent mayor Bob Parker in the local body elections of 9th October. Black and white and colour versions of this cartoon are available Quantity: 2 digital cartoon(s).

Research papers, University of Canterbury Library

This thesis seeks to examine how the integration of play, small toys specifically, and the use of solution-focused brief therapy techniques can affect the outcomes for primary school aged children undergoing counselling. The setting is a counselling agency in Christchurch, New Zealand. A qualitative research approach is used and the data analysed using a narrative inquiry approach. The context of this study is the counselling service of an agency where young children, adolescents and their families are helped and supported through a variety of life issues. The counselling the participants are offered uses a combination of a solution-focused and play therapy where the purpose is to encourage clients to find exceptions to their presenting problems and identify their preferred future. The aim of this study is to help the children navigate their problem through a better understanding of and the gaining of personal skills and strengths. Participants were invited to be part of this study through the agency waiting list. The four included presented with a variety of reasons for coming to counselling yet these proved similar to that which the agency has been routinely presented with in the aftermath of the Canterbury earthquakes from 2011 to present day. Each participant had the consent of their parents or caregivers to engage in this project. The participants themselves separately agreed to engage in a solution- focused counselling process where the counsellor also integrated the use of small toys as part of the course. Counselling sessions were audiotaped, aspects photographed and analysed with a specific focus on client engagement. Four key themes emerged as the participants explored their personal narrative. Firstly, the “I’m OK” theme depicted in their first scaling activity, secondly a recognition that things could indeed be better and they needed help. Thirdly, a realisation of their own strengths and skills and finally that the future was an optimistic place to look forward to. These themes are described and explained through descriptions of the participant’s stories as well as self-reflection by the researcher. Transcriptions of sessions are included as are excerpts from the research journal and photographs of the use of the small toys by the children.

Images, Alexander Turnbull Library

Text at top left reads 'Christchurch display portaloos' Four different styles of portaloo are shown; the "Merivale", the 'Sumner", the "Heritage" and the "Eastsider"; someone inside the 'Eastsider says 'At least I'm open plan AND mobile!' Context - After the tow Christchurch earthquakes and hundreds of aftershocks that have hit Christchurch one of the problems is lack of toilets because of damage to buildings and also damage to sewage systems so many portaloos and chemical toilets have been sent to Christchurch. However many people have resorted to the good old kiwi way and dug long-drops in the backyard. A website 'showusyourlongdrop.co.nz' has been developed by Christchurch man Jason Moore, who was inspired by photographs of Christchurch dunnies uploaded to Facebook. There has been a competition. Quantity: 1 digital cartoon(s).

Images, UC QuakeStudies

A motion-blurred photograph of houses, with the Port Hills in the background. The photographer comments, "This I hope gives you a feel of what it feels like in an earthquake. When you spend your whole life thinking that you and your home are built on solid ground, it can be quite a shock when you find it is not. You can feel the house shaking like a dog with a toy, rising up violently underneath you or the most gentle form which is when the ground moves gently like a wave moving under a rowing boat. It is not just the movement, you often get a rumbling sound which can precede a violent shake or can result in no movement at all. This means that some vehicles can sound like the rumbling initially and in the early days would get your heart racing. Another form of stress is when big excavators as heavy as a tank move as you can feel the ground shake from streets away, but you do not always hear the engine. For most of us the problem when the shaking starts, is wondering if this is the start of an extremely violent earthquake or will it peter out".

Research papers, University of Canterbury Library

In this paper we introduce CityViewAR, a mobile outdoor Augmented Reality (AR) application for providing AR information visualization on a city scale. The CityViewAR application was developed to provide geographical information about the city of Christchurch, which was hit by several major earthquakes in 2010 and 2011. The application provides information about destroyed buildings and historical sites that were affected by the earthquakes. The geo-located content is provided in a number of formats including 2D map views, AR visualization of 3D models of buildings on-site, immersive panorama photographs, and list views. The paper describes the iterative design and implementation details of the application, and gives one of the first examples of a study comparing user response to AR and non-AR viewing in a mobile tourism application. Results show that making such information easily accessible to the public in a number of formats could help people to have richer experience about cities. We provide guidelines that will be useful for people developing mobile AR applications for city-scale tourism or outdoor guiding, and discuss how the underlying technology could be used for applications in other areas.

Images, UC QuakeStudies

Graffiti on a wooden wall depicts a child pointing at a site across the street and reads "I remember when the Kazbah was over there." The photographer comments, "A local street artist has commemorated Christchurch's deadliest earthquake. The anniversary is tomorrow. Where the photograph was taken was the site of the Ozone Hotel, which has now gone as well. For some of us who live and work in the East of Christchurch the earthquake was not what happened in the City as we were almost unaware of it. We had no water, toilets and most of all no electricity for weeks. For myself petrol was low and with tales of all the petrol stations on our side of town being damaged we could not take the chance of venturing out on severely damaged roads to find no petrol and the possibility of not getting home. We walked around and saw the damage that was local to us. TJ's Kazbah was one that stood out. A building that had a beauty with its round tower standing proud and always looked well kept - it was now collapsed. Its tower, which was once pointing towards the sky was laying on its side. It had kept its shape, but had a lightning shaped crack through it. The one thing that kept us feeling almost normal through the coming weeks was The Press our daily paper still being delivered even though the Press building and staff had suffered so badly themselves.

Research papers, University of Canterbury Library

In the period between September 2010 and December 2011, Christchurch was shaken by a series of strong earthquakes including the MW7.1 4 September 2010, Mw 6.2 22 February 2011, MW6.2 13 June 2011 and MW6.0 23 December 2011 earthquakes. These earthquakes produced very strong ground motions throughout the city and surrounding areas that resulted in soil liquefaction and lateral spreading causing substantial damage to buildings, infrastructure and the community. The stopbank network along the Kaiapoi and Avon River suffered extensive damage with repairs projected to take several years to complete. This presented an opportunity to undertake a case-study on a regional scale of the effects of liquefaction on a stopbank system. Ultimately, this information can be used to determine simple performance-based concepts that can be applied in practice to improve the resilience of river protection works. The research presented in this thesis draws from data collected following the 4th September 2010 and 22nd February 2011 earthquakes. The stopbank damage is categorised into seven key deformation modes that were interpreted from aerial photographs, consultant reports, damage photographs and site visits. Each deformation mode provides an assessment of the observed mechanism of failure behind liquefaction-induced stopbank damage and the factors that influence a particular style of deformation. The deformation modes have been used to create a severity classification for the whole stopbank system, being ‘no or low damage’ and ‘major or severe damage’, in order to discriminate the indicators and factors that contribute to ‘major to severe damage’ from the factors that contribute to all levels of damage a number of calculated, land damage, stopbank damage and geomorphological parameters were analysed and compared at 178 locations along the Kaiapoi and Avon River stopbank systems. A critical liquefiable layer was present at every location with relatively consistent geotechnical parameters (cone resistance (qc), soil behaviour type (Ic) and Factor of Safety (FoS)) across the study site. In 95% of the cases the critical layer occurred within two times the Height of the Free Face (HFF,). A statistical analysis of the geotechnical factors relating to the critical layer was undertaken in order to find correlations between specific deformation modes and geotechnical factors. It was found that each individual deformation mode involves a complex interplay of factors that are difficult to represent through correlative analysis. There was, however, sufficient data to derive the key factors that have affected the severity of deformation. It was concluded that stopbank damage is directly related to the presence of liquefaction in the ground materials beneath the stopbanks, but is not critical in determining the type or severity of damage, instead it is merely the triggering mechanism. Once liquefaction is triggered it is the gravity-induced deformation that causes the damage rather than the shaking duration. Lateral spreading and specifically the depositional setting was found to be the key aspect in determining the severity and type of deformation along the stopbank system. The presence or absence of abandoned or old river channels and point bar deposits was found to significantly influence the severity and type of deformation. A review of digital elevation models and old maps along the Kaiapoi River found that all of the ‘major to severe’ damage observed occurred within or directly adjacent to an abandoned river channel. Whilst a review of the geomorphology along the Avon River showed that every location within a point bar deposit suffered some form of damage, due to the depositional environment creating a deposit highly susceptible to liquefaction.

Images, UC QuakeStudies

Two images of a house, taken before and after the earthquakes. In the after photograph the chimneys are gone, a column supporting the car port has partly collapsed, windows are broken, and the previously neat lawn and driveway are overgrown. The photographer comments, "This was a house that I was selling up to the September 2010 earthquake in Christchurch. It was on Avonside Drive, which was an area that has been badly hit in every earthquake that has hit the area. In the September quake parts of the house moved in different directions and one of the upstairs doors had to be smashed open to release one of the sons from his bedroom. This occurred in the dark with numerous aftershocks shaking the house. Liquefaction poured up through the floor and flowed down the drive. Everyone got out OK, but soon after the house was red stickered meaning it was dangerous to enter. The house was looted many times even though there was constant police patrols. When the most violent earthquake occurred on 22 February 2012 both the tall heavy chimneys came crashing through into the living areas. Subsequent earthquakes and aftershocks have caused one of the brick fence pillars to fall and the front garage pillar to break up and twist. The family's troubles did not end there. They moved into the home of one of their parents and this mansion of a home was so badly affected by the February earthquake that no one could enter to collect any of their or their parents' belongings. They now own a new home, which they are fond of except when the ground shakes yet again. There has been to date 10,712 earthquakes and aftershocks since 4 September 2010".

Audio, Radio New Zealand

DAVID BENNETT to the Minister of Finance: How is the Government's economic programme helping to keep interest rates lower during this economic cycle, compared to the previous economic cycle in the mid-2000s? Dr RUSSEL NORMAN to the Minister of Energy and Resources: How much more is an average New Zealand household that uses 8,000kwh of power annually paying for electricity per year as of November 2013 compared to November 2008, according to the Ministry of Business, Innovation, and Employment's latest Quarterly Survey of Domestic Electricity Prices? Hon DAVID PARKER to the Minister of Finance: What will he do to "spread some of the benefits of growth" when hourly wage rates have only grown by 1.6 percent in the year to December 2013, which is close to 0 percent in real terms, when 45 percent of listed corporates have double-digit profit growth? JACQUI DEAN to the Minister for the Environment: What recent announcements has the Government made on the classification for drilling for oil and gas in New Zealand's Exclusive Economic Zone? GRANT ROBERTSON to the Minister of Justice: When she told the House yesterday "I had previously told Oravida that it could not use my name or photograph to endorse or promote its business products or services" when was that and what specific circumstances did it relate to? COLIN KING to the Minister for Tertiary Education, Skills and Employment: How is the Youth Guarantee Scheme helping the Government achieve the Better Public Services target of 85 percent of all 18-year-olds achieving NCEA Level two or an equivalent qualification in 2017? CAROL BEAUMONT to the Minister of Women's Affairs: Does she have confidence in the Ministry of Women's Affairs given their 2013 Annual Report shows that six out of seven policy outcomes have stayed the same or gone backwards in the last past year; if so, why? SCOTT SIMPSON to the Minister for Courts: How is the Government improving the way the Disputes Tribunal works to make it easier for New Zealanders to resolve civil disputes? Hon TREVOR MALLARD to the Minister of Internal Affairs: What action, if any, has he taken this year to show the Prime Minister that he has met the highest ethical standards required by Section 2.53 of the Cabinet Manual? ALFRED NGARO to the Minister of Pacific Island Affairs: What steps is the Government taking to lift the skills of Pacific people in New Zealand? DENIS O'ROURKE to the Minister for Canterbury Earthquake Recovery: Does he accept the conclusion in the Human Rights Commission's report Monitoring Human Rights in the Canterbury Earthquake Recovery that "many people affected by the earthquakes continue to experience deteriorating standards of living and impacts on their quality of life that go beyond the immediate effects of the disaster"? CATHERINE DELAHUNTY to the Minister of Energy and Resources: Has he had any discussions with any Indian Government Ministers about selling Solid Energy assets?

Research papers, University of Canterbury Library

The Leader Fault was one of at least 17 faults that ruptured the ground surface across the northeastern South Island of New Zealand during the Mw 7.8 2016 Kaikōura Earthquake. The southern ~6 km of the Leader Fault, here referred to as the South Leader Fault (SLF), ruptured the North Canterbury (tectonic) Domain and is the primary focus of this study. The main objective of the thesis is to understand the key factors that contributed to the geometry and kinematics of the 2016 SLF rupture and its intersection with The Humps Fault (HF). This thesis employs a combination of techniques to achieve the primary objective, including detailed mapping of the bedrock geology, geomorphology and 2016 rupture, measurement of 2016 ground surface displacements, kinematic analysis of slip vectors from the earthquake, and logging of a single natural exposure across a 2016 rupture that was treated as a paleoseismic trench. The resulting datasets were collected in the field, from terrestrial LiDAR and InSAR imagery, and from historical (pre-earthquake) aerial photographs for a ~11 km2 study area. Surface ruptures in the study area are a miniature version of the entire rupture from the earthquake; they are geometrically and kinematically complex, with many individual and discontinuous segments of varying orientations and slip senses which are distributed across a zone up to ~3.5 km wide. Despite this variability, three main groups of ruptures have been identified. These are: 1) NE-SW striking, shallow to moderate dipping (25-45°W) faults that are approximately parallel to Cenozoic bedding with mainly reverse dip-slip and, and for the purposes of this thesis, are considered to be part of the SLF. 2) N-S striking, steeply dipping (~85°E) oblique sinistral faults that are up to the west and part of the SLF. 3) E-NE striking, moderate to steeply dipping (45-68°N) dextral reverse faults which are part of the HF. Bedding-parallel faults are interpreted to be flexural slip structures formed during folding of the near-surface Cenozoic strata, while the steeply dipping SLF ruptured a pre-existing bedrock fault which has little topographic expression. Groups 1 and 2 faults were both locally used for gravitational failure during the earthquake. Despite this non-tectonic fault movement, the slip vectors for faults that ruptured during the earthquake are broadly consistent with NCD tectonics and the regional ~100-120° trend of the principal horizontal stress/strain axes. Previous earthquake activity on the SLF is required by its displacement of Cenozoic formations but Late Quaternary slip on the fault prior to 2016 is neither supported by pre-existing fault scarps nor by changes in topography across the fault. By contrast, at least two earthquakes (including 2016) appear to have ruptured the HF from the mid Holocene, consistent with recurrence intervals of no more than ~7 kyr, and with preliminary observations from trenches on the fault farther to the west. The disparity in paleoearthquake records of the two faults suggests that they typically do not rupture together, thus it is concluded that the HF-SLF rupture pattern observed in the Kaikōura Earthquake rarely occurs in a single earthquake.

Research papers, University of Canterbury Library

Following the Mw 6.2 Christchurch Earthquake on 22 February 2011, extensive ground cracking in loessial soils was reported in some areas of the Port Hills, southeast of central Christchurch. This study was undertaken to investigate the mechanisms of earthquake-induced ground damage on the eastern side of the Hillsborough Valley. A zone of extensional cracking up to 40m wide and 600m long was identified along the eastern foot-slope, accompanied by compression features and spring formation at the toe of the slope. An engineering geological and geomorphological model was developed for the eastern Hillsborough Valley that incorporates geotechnical investigation data sourced from the Canterbury Geotechnical Database (CGD), the findings of trenching and seismic refraction surveying carried out for this research, and interpretation of historical aerial photographs. The thickness and extent of a buried peat swamp at the base of the slope was mapped, and found to coincide with significant compression features. Ground cracking was found to have occurred entirely within loess-colluvium and to follow the apices of pre-1920s tunnel-gully fan debris at the southern end of the valley. The ground-cracking on the eastern side of the Hillsborough Valley is interpreted to have formed through tensile failure of the loess-colluvium. Testing was carried out to determine the tensile strength of Port Hills loess colluvium as a function of water content and density, in order to better understand the occurrence and distribution of the observed ground cracking. A comprehensive review of the soil tensile strength testing literature was undertaken, from which a test methodology was developed. Results show remoulded loess-colluvium to possess tensile strength of 7 - 28 kPa across the range of tested moisture contents (10-15%) and dry densities (1650-1900kg/m3). A positive linear relationship was observed between tensile strength and dry density, and a negative linear relationship between moisture content and tensile strength. The observed ground damage and available geotechnical information (inclinometer and piezometer records provided by the Earthquake Commission) were together used to interpret the mechanism(s) of slope movement that occurred in the eastern Hillsborough Valley. The observed ground damage is characteristic of translational movement, but without the development of lateral release scarps, or a basal sliding surface - which was not located during drilling. It is hypothesised that shear displacement has been accommodated by multiple slip surfaces of limited extent within the upper 10m of the slope. Movement has likely occurred within near-saturated colluvial units that have lost strength during earthquake shaking. The eastern Hillsborough Valley is considered to be an ‘incipient translational slide’, as both the patterns of damage and shearing are consistent with the early stages of such slide development. Sliding block analysis was utilised to understand how the eastern Hillsborough Valley may perform in a future large magnitude earthquake. Known cumulative displacements of ~0.3m for eastern Hillsborough Valley during the 2010-2011 Canterbury Earthquake Sequence were compared with modelled slope displacements to back-analyse a lower-bound yield acceleration of 0.2 - 0.25g. Synthetic broadband modelling for future Alpine and Hope Fault earthquakes indicates PGAs of approximately 0.08g for soil sites in the Christchurch area, as such, slope movement is unlikely to be reactivated by an Alpine Fault or Hope Fault earthquake. This does not take into account the possible role of strength loss due to excess pore pressure that may occur during these future events.

Research papers, University of Canterbury Library

Coastal and river environments are exposed to a number of natural hazards that have the potential to negatively affect both human and natural environments. The purpose of this research is to explain that significant vulnerabilities to seismic hazards exist within coastal and river environments and that coasts and rivers, past and present, have played as significant a role as seismic, engineering or socio-economic factors in determining the impacts and recovery patterns of a city following a seismic hazard event. An interdisciplinary approach was used to investigate the vulnerability of coastal and river areas in the city of Christchurch, New Zealand, following the Canterbury Earthquake Sequence, which began on the 4th of September 2010. This information was used to identify the characteristics of coasts and rivers that make them more susceptible to earthquake induced hazards including liquefaction, lateral spreading, flooding, landslides and rock falls. The findings of this research are applicable to similar coastal and river environments elsewhere in the world where seismic hazards are also of significant concern. An interdisciplinary approach was used to document and analyse the coastal and river related effects of the Canterbury earthquake sequence on Christchurch city in order to derive transferable lessons that can be used to design less vulnerable urban communities and help to predict seismic vulnerabilities in other New Zealand and international urban coastal and river environments for the future. Methods used to document past and present features and earthquake impacts on coasts and rivers in Christchurch included using maps derived from Geographical Information Systems (GIS), photographs, analysis of interviews from coastal, river and engineering experts, and analysis of secondary data on seismicity, liquefaction potential, geology, and planning statutes. The Canterbury earthquake sequence had a significant effect on Christchurch, particularly around rivers and the coast. This was due to the susceptibility of rivers to lateral spreading and the susceptibility of the eastern Christchurch and estuarine environments to liquefaction. The collapse of river banks and the extensive cracking, tilting and subsidence that accompanied liquefaction, lateral spreading and rock falls caused damage to homes, roads, bridges and lifelines. This consequently blocked transportation routes, interrupted electricity and water lines, and damaged structures built in their path. This study found that there are a number of physical features of coastal and river environments from the past and the present that have induced vulnerabilities to earthquake hazards. The types of sediments found beneath eastern Christchurch are unconsolidated fine sands, silts, peats and gravels. Together with the high water tables located beneath the city, these deposits made the area particularly susceptible to liquefaction and liquefaction-induced lateral spreading, when an earthquake of sufficient size shook the ground. It was both past and present coastal and river processes that deposited the types of sediments that are easily liquefied during an earthquake. Eastern Christchurch was once a coastal and marine environment 6000 years ago when the shoreline reached about 6 km inland of its present day location, which deposited fine sand and silts over this area. The region was also exposed to large braided rivers and smaller spring fed rivers, both of which have laid down further fine sediments over the following thousands of years. A significant finding of this study is the recognition that the Canterbury earthquake sequence has exacerbated existing coastal and river hazards and that assessments and monitoring of these changes will be an important component of Christchurch’s future resilience to natural hazards. In addition, patterns of recovery following the Canterbury earthquakes are highlighted to show that coasts and rivers are again vulnerable to earthquakes through their ability to recovery. This city’s capacity to incorporate resilience into the recovery efforts is also highlighted in this study. Coastal and river areas have underlying physical characteristics that make them increasingly vulnerable to the effects of earthquake hazards, which have not typically been perceived as a ‘coastal’ or ‘river’ hazard. These findings enhance scientific and management understanding of the effects that earthquakes can have on coastal and river environments, an area of research that has had modest consideration to date. This understanding is important from a coastal and river hazard management perspective as concerns for increased human development around coastlines and river margins, with a high seismic risk, continue to grow.