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Images, eqnz.chch.2010

Christchurch city experienced a magnitude 7.1 earthquake on September 4 at 4:35 am. The epicentre was 40 km west of the city. It was the most damaging earthquake in New Zealand since the Hawke's Bay earthquake in 1931, but there was no loss of life. It was fortunate the earthquake occurred when the central city streets were deserted, as there w...

Research papers, University of Canterbury Library

This paper investigates the effects of variability in source rupture parameters on site-specific physics-based simulated ground motions, ascertained through the systematic analysis of ground motion intensity measures. As a preliminary study, we consider simulations of the 22 February 2011 Christchurch earthquake using the Graves and Pitarka (2015) methodology. The effects of source variability are considered via a sensitivity study in which parameters (hypocentre location, earthquake magnitude, average rupture velocity, fault geometry and the Brune stress parameter) are individually varied by one standard deviation. The sensitivity of simulated ground motion intensity measures are subsequently compared against observational data. The preliminary results from this study indicate that uncertainty in the stress parameter and the rupture velocity have the most significant effect on the high frequency amplitudes. Conversely, magnitude uncertainty was found to be most influential on the spectral acceleration amplitudes at low frequencies. Further work is required to extend this preliminary study to exhaustively consider more events and to include parameter covariance. The ultimate results of this research will assist in the validation of the overall simulation method’s accuracy in capturing various rupture parameters, which is essential for the use of simulated ground motion models in probabilistic seismic hazard analysis.

Research papers, University of Canterbury Library

In the last two decades, New Zealand (NZ) has experienced significant earthquakes, including the 2010 M 7.2 Darfield, 2011 M 6.2 Christchurch, and 2016 M 7.8 Kaikōura events. Amongst these large events, tens of thousands of smaller earthquakes have occurred. While previous event and ground-motion databases have analyzed these events, many events below M 4 have gone undetected. The goal of this study is to expand on previous databases, particularly for small magnitude (M<4) and low-amplitude ground motions. This new database enables a greater understanding of regional variations within NZ and contributes to the validity of internationally developed ground-motion models. The database includes event locations and magnitude estimates with uncertainty considerations, and tectonic type assessed in a hierarchical manner. Ground motions are extracted from the GeoNet FDSN server and assessed for quality using a neural network classification approach. A deep neural network approach is also utilized for picking P and S phases for determination of event hypocentres. Relative hypocentres are further improved by double-difference relocation and will contribute toward developing shallow (< 50 km) seismic tomography models. Analysis of the resulting database is compared with previous studies for discussion of implications toward national hazard prediction models.

Research papers, University of Canterbury Library

Active faults capable of generating highly damaging earthquakes may not cause surface rupture (i.e., blind faults) or cause surface ruptures that evade detection due to subsequent burial or erosion by surface processes. Fault populations and earthquake frequency-­‐magnitude distributions adhere to power laws, implying that faults too small to cause surface rupture but large enough to cause localized strong ground shaking densely populate continental crust. The rupture of blind, previously undetected faults beneath Christchurch, New Zealand in a suite of earthquakes in 2010 and 2011, including the fatal 22 February 2011 moment magnitude (Mw) 6.2 Christchurch earthquake and other large aftershocks, caused a variety of environmental impacts, including major rockfall, severe liquefaction, and differential surface uplift and subsidence. All of these effects occurred where geologic evidence for penultimate effects of the same nature existed. To what extent could the geologic record have been used to infer the presence of proximal, blind and / or unidentified faults near Christchurch? In this instance, we argue that phenomena induced by high intensity shaking, such as rock fragmentation and rockfall, revealed the presence of proximal active faults in the Christchurch area prior to the recent earthquake sequence. Development of robust earthquake shaking proxy datasets should become a higher scientific priority, particularly in populated regions.

Images, eqnz.chch.2010

Today is the anniversary of the 7.1 magnitude earthquake that hit Canterbury on 4 September 2010, and two lights - The White Lights of Hope - were turned on this evening from the square to help fill the city's "dark heart" and remind residents to look forward to a bright future. Note: While I was capturing this image we had a ...

Images, eqnz.chch.2010

Kia Kaha (in the little red love-heart on the fence) can be translated from the Maori language as “Be strong and fearless!” “Be Proud!” or “Stand tall!” The term is used in many situations to give encouragement and support to family, friends and mates. Taken one week after the 6.3 magnitude quake hit Christchurch 22 February 2011. Proce...

Images, eqnz.chch.2010

The Cathedral of the Blessed Sacrament, Christcurch, after the 6.3 magnitude quake on 22 February 2011. When The Angels Fall Take your father's cross Gently from the wall A shadow still remaining See the churches fall In mighty arcs of sound And all that they're containing Yet all the rugged souls Looking for their lost homes Shuffle to...

Images, eqnz.chch.2010

Today is the anniversary of the 7.1 magnitude earthquake that hit Canterbury on 4 September 2010, and two lights - The White Lights of Hope - were turned on this evening from the square to help fill the city's "dark heart" and remind residents to look forward to a bright future. Note: While I was capturing this image we had a ...

Images, eqnz.chch.2010

Demolition continues on the old Beckenham shops after the 7.1 magnitude earthquake in Christchurch on the 4th September 2010. So sad to see history die - both buildings and business. Took this image in HDR and processed in PhotoMatix and PaintShop Pro 8. Below are two other images of the shops one soon after the earthquake and the other sever...

Images, eqnz.chch.2010

This statue of the Virgin Mary stood in the south tower of The Cathedral of the Blessed Sacrament and had been facing inside from when she was placed there and through the September 2010 earthquake. That changed on February 22 2010 at 12.51pm when Christchurch was rocked by a 6.3 magnitude earthquake. During the violent shaking motion Mary was t...

Audio, Radio New Zealand

We're broadcasting today from Christchurch on the second anniversary of the six point three magnitude earthquake which devastated this city. One hundred and eighty five died in the quake and today at midday a memorial service will be held in Latimer Square. After two years, the pace of the rebuild is growing, but for some, so is frustration. More than seven thousand property owners in the residential red zone received a buyout offer from the government. Most of those have taken it - but there are a few who haven't.

Audio, Radio New Zealand

When the 6.3 magnitude earthquake struck Christchurch at 2:20 on Monday afternoon Barry Ross was outside his home at Godley Head on the Port Hills, where is he is the Department of Conservation caretaker. Barry's house is thought to be the closest to the epicentre that day and such was the force of the quake he was thrown to the ground and some of the cliff nearby fell away. He lost power and water for a few days but now he's back home, clearing up and determined to get on with life.

Audio, Radio New Zealand

Thousands of people in Christchurch and around the country paused at 12.51 on Monday afternoon to mark a decade since the February 22 magnitude 6.3 earthquake which claimed 185 lives. It was 10 years ago today when an ordinary Christchurch day turned to hell for so many. But in contrast to the harrowing scenes and sounds of that day, today a large peaceful crowd gathered at the Civic Memorial Service on the banks of the Avon River under large oak trees. Reporter Sally Murphy and cameraman Nate McKinnon were there.

Audio, Radio New Zealand

As the fourth anniversary of the earthquake which devastated Christchurch approaches, the slow pace of the rebuild has surprised many. But how quickly have other earthquake hit cities returned to their former glory? Radio New Zealand Christchurch reporter, Rachel Graham, visited Japan for an Insight documentary to compare the progress made in the Sendai area, almost four years after it was hit by a magnitude 9 earthquake and a mega tsunami. She also visited Kobe to look at the impact on that city, and the lessons learnt, 20 years after it was hit by a major earthquake.

Audio, Radio New Zealand

Nearly two-thirds of MPs have voted in support of a bill that would legalise euthanasia. The Government says it will consider moves to rein in rapidly rising salaries for top public servants. It's been far from smooth sailing for the new government in its first eight weeks in office, but it appears to be largely on track to deliver its hundred day plan. More than a year after North Canterbury's 7.8 magnitude earthquake forced its closure, State Highway 1 north of Kaikoura will re-open to the public on Friday. 

Research papers, University of Canterbury Library

A zone of active tectonism occurs in mid and north Canterbury, from the Rakaia to the Waipara Rivers, which coincides with seismicity concentrations and several Quaternary surface anomalies and is here defined as the Porters Pass Tectonic Zone. Although parallel to the Marlborough faults to the north, the lack of regional definition suggests this zone is much younger in its inception reflecting a southward movement of the plate rotation vector. The objectives of this study were to map the structures associated with this zone in the segment between the Rakaia and Waimakariri Rivers with detailed analysis concentrated in the upper Kawai Valley. Quaternary offsets on the main lineament of the Porters Pass Fault were traced through the area and evidence for the rate of movement, probable magnitudes and return periods of related seismic events was sought. The basement was found to be complicated by pre-existing deformation structures in Torlesse Group rocks which have been subsequently been re-activated or rotated by recent fault movement probably beginning in the Pleistocene. This phase is dominantly thrusting and uplift has lead to the erosion of most of the overlying sedimentary cover. Remnants of the Cret-Tertiary sediments still remain as fault-bounded packets. Evidence suggests that a change to development of a regional lateral shear associated with the Porters Pass Tectonic Zone transects the thrust system with complex interaction between the older reverse and new strike-slip faults. Offset rates along the segments of the Porters Pass Fault are not well constrained but are believed to be approximately in the range of 11-13 mm/year for at least the last 130,000 years. This rate is similar to other large faults in the Marlborough region. Two earthquake events have been identified and dated at 600 and 2000 years ago, with a magnitude of greater than 6.5. Evidence suggests characteristic earthquakes along the Porters Pass Fault are greater than Magnitude 7. This result has some major ramifications for the expected seismic hazards for nearby Christchurch.

Images, Alexander Turnbull Library

The cartoon shows the hands of two people joined in mutual despair and kindness. One represents 'Christchurch' and the other the 'Pike River Mine'. Context - the 7.1 earthquake on 4 September 2010 in Christchurch in which there was a lot of damage but no deaths, the Pike River Mine disaster which occurred on the West Coast on 19 November 2010 and caused the deaths of 29 coal miners and now on 22 February 2011 a 6.3 magnitude earthquake in Christchurch which has probably killed more than 200 people (at this point the number is still not known) and caused much more severe damage. The reason the apparently lesser magnitude quake caused more destruction is because it was very shallow, was in the middle of the day and struck very close to the centre of the city. Colour and black and white versions of this cartoon are available Quantity: 2 digital cartoon(s).

Research Papers, Lincoln University

On 4 September 2010, a 7.1 magnitude earthquake struck near Darfield, 40 kilometres west of Christchurch, New Zealand. The quake caused significant damage to land and buildings nearby, with damage extending to Christchurch city. On 22 February 2011, a 6.3 magnitude earthquake struck Christchurch, causing extensive and significant damage across the city and with the loss of 185 lives. Years on from these events, occasional large aftershocks continue to shake the region. Two main entomological collections were situated within close proximity to the 2010/11 Canterbury earthquakes. The Lincoln University Entomology Research Collection, which is housed on the 5th floor of a 7 storey building, was 27.5 km from the 2010 Darfield earthquake epicentre. The Canterbury Museum Entomology Collection, which is housed in the basement of a multi-storeyed heritage building, was 10 km from the 2011 Christchurch earthquake epicentre. We discuss the impacts of the earthquakes on these collections, the causes of the damage to the specimens and facilities, and subsequent efforts that were made to prevent further damage in the event of future seismic events. We also discuss the wider need for preparedness against the risks posed by natural disasters and other catastrophic events.

Articles, UC QuakeStudies

This report was the first report in the district series, and has a different format to later reports. It includes all natural hazards, not only earthquake hazards. It describes earthquake, flooding, meteorological, landslide and coastal hazards within Hurunui district and gives details of historic events. It includes district-scale (1:250,000) active fault and flood hazard maps. The report describes an earthquake scenario for a magnitude 6.9 earthquake near Cheviot, as well as flooding, meteorological, landslide, coastal erosion, storm surge, and tsunami scenarios.

Articles, UC QuakeStudies

This report was the first report in the district series, and has a different format to later reports. It includes all natural hazards, not only earthquake hazards. It describes earthquake, flooding, meteorological, landslide and coastal hazards within Hurunui district and gives details of historic events. It includes district-scale (1:250,000) active fault and flood hazard maps. The report describes an earthquake scenario for a magnitude 6.9 earthquake near Cheviot, as well as flooding, meteorological, landslide, coastal erosion, storm surge, and tsunami scenarios. See Object Overview for background and usage information.

Research papers, University of Canterbury Library

A magnitude 6.3 earthquake struck the city of Christchurch at 12:51pm on Tuesday 22 February 2011. The earthquake caused 182 fatalities, a large number of injuries, and resulted in widespread damage to the built environment, including significant disruption to the lifelines. The event created the largest lifeline disruption in a New Zealand city in 80 years, with much of the damage resulting from extensive and severe liquefaction in the Christchurch urban area. The Christchurch earthquake occurred when the Canterbury region and its lifelines systems were at the early stage of recovering from the 4 September 2010 Darfield (Canterbury) magnitude 7.1 earthquake. This paper describes the impact of the Christchurch earthquake on lifelines by briefly summarising the physical damage to the networks, the system performance and the operational response during the emergency management and the recovery phase. Special focus is given to the performance and management of the gas, electric and road networks and to the liquefaction ejecta clean-up operations that contributed to the rapid reinstatement of the functionality of many of the lifelines. The water and wastewater system performances are also summarized. Elements of resilience that contributed to good network performance or to efficient emergency and recovery management are highlighted in the paper.

Images, Alexander Turnbull Library

Roger Sutton, former chief executive of the the power lines company, Orion and since June 2011 Chief Executive Officer of the Canterbury Earhquake Recovery Authority, is shown in a straitjacket, raving. An unseen interviewer asks him how it feels after 'two years in the job'. Roger Sutton's work in leading the Earthquake Authority after the February earthquake was extremely stressful, considering the magnitude of the task. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

The Amuri Earthquake of September 1, 1888 (magnitude M = 6.5 to 6.8) occurred on the Hope River Segment of the Hope Fault west of Hanmer Plains. The earthquake was felt strongly in North Canterbury and North Westland and caused considerable property damage and landsliding in the Lower Hope Valley. However, damage reports and the spatial distribution of felt intensities emphasize extreme variations in seismic effects over short distances, probably due to topographic focusing and local ground conditions. Significant variations in lateral fault displacement occurred at secondary fault segment boundaries (side-steps and bends in the fault trace) during the 1888 earthquake. This historical spatial variation in lateral slip is matched by the Late Quaternary geomorphic distribution of slip on the Hope River Segment of the Hope Fault. Trenching studies at two sites on the Hope Fault have also identified evidence for five pre-historic earthquakes of similar magnitude to the 1888 earthquake and an average recurrence interval of 134 ± 27 years between events. Magnitude estimates for the 1888 earthquake are combined with a. strong ground motion attenuation expression to provide an estimate of potential ground accelerations in Amuri District during-future earthquakes on the Hope River Segment of the Hope Fault. The predicted acceleration response on bedrock sites within 20 km of the epicentral region is between 0.23 g and 0.34 g. The close match between the historic, inferred pre-historic and geomorphic distribution of lateral slip indicates that secondary fault segmentation exerts a strong structural control on rupture propagation and the expression of fault displacement at the surface. In basement rocks at depth the spatial variations in slip are inferred to be distributed within zones of pervasive cataclastic shear, on either side of the fault segment boundaries. The large variations in surface displacement across fault segment boundaries means that one must know the geometry of the fault in order to evaluate slip-rates calculated from individual locations. The average Late Quaternary slip-rate on the Hope Fault at Glynn Wye Station is between 15.5 mm/yr and 18.25 mm/yr and the rate on the subsidiary Kakapo Fault is between 5.0 mm/yr and 7.5 mm/yr. These rates have been determined from sites which are relatively free of structural complication.

Research papers, University of Canterbury Library

Recently developed performance-based earthquake engineering framework, such as one provided by PEER (Deierlein et al. 2003), assist in the quantification in terms of performance such as casualty, monetary losses and downtime. This opens up the opportunity to identify cost-effective retrofit/rehabilitation strategies by comparing upfront costs associated with retrofit with the repair costs that can be expected over time. This loss assessment can be strengthened by learning from recent earthquakes, such as the 2010 Canterbury and 2016 Kaikoura earthquakes. In order to investigate which types of retrofit/rehabilitation strategies may be most cost-effective, a case study building was chosen for this research. The Pacific Tower, a 22-storey EBF apartment located within the Christchurch central business district (CBD), was damaged and repaired during the 2010 Canterbury earthquake series. As such, by taking hazard levels accordingly (i.e. to correspond to the Christchurch CBD), modelling and analysing the structure, and considering the vulnerability and repair costs of its different components, it is possible to predict the expected losses of the aforementioned building. Using this information, cost-effective retrofit/rehabilitation strategy can be determined. This research found that more often than not, it would be beneficial to improve the performance of valuable non-structural components, such as partitions. Although it is true that improving such elements will increase the initial costs, over time, the benefits gained from reduced losses should be expected to overcome the initial costs. Aftershocks do increase the predicted losses of a building even in lower intensities due to the fact that non-structural components can get damaged at such low intensities. By comparing losses computed with and without consideration of aftershocks for a range of historical earthquakes, it was found that the ratio between losses due to main shock with aftershocks to the losses due to the main shock only tended to increase with increasing main shock magnitude. This may be due to the fact that larger magnitude earthquakes tend to generate larger magnitude aftershocks and as those aftershocks happen within a region around the main shock, they are more likely to cause intense shaking and additional damage. In addition to this observation, it was observed that the most significant component of loss of the case study building was the non-structural partition walls.

Audio, Radio New Zealand

After the magnitude 7.1 earthquake struck Canterbury on 4 September 2010, most media reports claimed that no lives had been lost. But In fact, this first earthquake killed at least 3000 chickens, eight cows, one dog, a lemur and 150 aquarium fish. University of Canterbury associate professor Annie Potts, along with co-author Donelle Gadenne, wrote Animals in Emergencies: Learning from the Christchurch Earthquakes, revealing what happened to the animals during and after the series of quakes. Annie Potts will give a public lecture, 'Animals and natural disasters: Learning from recent earthquakes', on Thursday 16 March, 7pm at UC Ilam campus, Christchurch. Register to attend free at: www.canterbury.ac.nz/ucconnect

Images, eqnz.chch.2010

When I lived in Christchurch back in 2004-2005, this was a building I went past on the bus every day to get to and from work in the city. After the big quake on 04/09/10 (7.1 magnitude), its been seriously damaged. As have many more of the shops in this area. Thankfully no lives were lost in the quake, and I'm glad I wasnt there to feel it eith...

Research Papers, Lincoln University

The magnitude 7.8 earthquake that struck North Canterbury, on the east coast of New Zealand’s South Island on 14 November 2016 had significant impacts and implications for the community of Kaikōura and surrounding settlements. The magnitude and scope of this event has resulted in extensive and ongoing geological and geophysical research into the event. The current paper complements this research by providing a review of existing social science research and offering new analysis of the impact of the earthquake and its aftermath on community resilience in Kaikōura over the past five years. Results demonstrate the significant economic implications for tourism, and primary industries. Recovery has been slow, and largely dependent on restoring transportation networks, which helped catalyse cooperation among local hospitality providers. Challenges remain, however, and not all sectors or households have benefited equally from post-quake opportunities, and long-term recovery trajectories continue to be hampered by COVID-19 pandemic. The multiple ongoing and future stressors faced by Kaikōura require integrated and equitable approaches in order to build capability and capacity for locally based development pathways to ensure long-term community resilience.

Research papers, University of Canterbury Library

This research employs a deterministic seismic risk assessment methodology to assess the potential damage and loss at meshblock level in the Christchurch CBD and Mount Pleasant primarily due to building damage caused by earthquake ground shaking. Expected losses in terms of dollar value and casualties are calculated for two earthquake scenarios. Findings are based on: (1) data describing the earthquake ground shaking and microzonation effects; (2) an inventory of buildings by value, floor area, replacement value, occupancy and age; (3) damage ratios defining the performance of buildings as a function of earthquake intensity; (4) daytime and night-time population distribution data and (5) casualty functions defining casualty risk as a function of building damage. A GIS serves as a platform for collecting, storing and analyzing the original and the derived data. It also allows for easy display of input and output data, providing a critical functionality for communication of outcomes. The results of this study suggest that economic losses due to building damage in the Christchurch CBD and Mount Pleasant will possibly be in the order of $5.6 and $35.3 million in a magnitude 8.0 Alpine fault earthquake and a magnitude 7.0 Ashley fault earthquake respectively. Damage to non-residential buildings constitutes the vast majority of the economic loss. Casualty numbers are expected to be between 0 and 10.