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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.

Research papers, University of Canterbury Library

Using case studies from the 2010-2011 Canterbury, New Zealand earthquake sequence, this study assesses the accuracies of paleoliquefaction back-analysis methods and explores the challenges, techniques, and uncertainties associated with their application. While liquefaction-based back-analyses have been widely used to estimate the magnitudes of paleoearthquakes, their uncertain efficacies continue to significantly affect the computed seismic hazard in regions where they are relied upon. Accordingly, their performance is evaluated herein using liquefaction data from modern earthquakes with known magnitudes. It is shown that when the earthquake source location and mechanism are known, back-analysis methods are capable of accurately deriving seismic parameters from liquefaction evidence. However, because the source location and mechanism are often unknown in paleoseismic studies, and because accurate interpretation is shown to be more difficult in such cases, new analysis techniques are proposed herein. An objective parameter is proposed to geospatially assess the likelihood of any provisional source location, enabling an analyst to more accurately estimate the magnitude of a liquefaction-inducing paleoearthquake. This study demonstrates the application of back-analysis methods, provides insight into their potential accuracies, and provides a framework for performing paleoliquefaction analyses worldwide.

Research papers, University of Canterbury Library

This study provides an initial examination of source parameter uncertainty in a New Zealand ground motion simulation model, by simulating multiple event realisations with perturbed source parameters. Small magnitude events in Canterbury have been selected for this study due to the small number of source input parameters, the wealth of recorded data, and the lack of appreciable off-fault non-linear effects. Which provides greater opportunity to identify systematic source, path and site effects, required to robustly investigate the causes of uncertainty.

Audio, Radio New Zealand

The Prime Minister prepares for the Christchurch Call Summit in Paris saying governments need to protect their citizens from radicalisation, Police investigate who sent a threatening letter to the Earthquake Commission, A powerful 7.5 magnitude quake strikes PNG overnight.

Images, eqnz.chch.2010

Photos taken at the Lyttelton Community briefing held on March 7 2011 following the magnitude 6.3 earthquake on 22 February 2011. File Ref: CCL-2011-03-07-Lyttelton-Community-Briefing-P1110625 From the collection of Christchurch City Libraries.

Images, eqnz.chch.2010

Photos taken at the Lyttelton Community briefing held on March 7 2011 following the magnitude 6.3 earthquake on 22 February 2011. File Ref: CCL-2011-03-07-Lyttelton-Community-Briefing-P1110622 From the collection of Christchurch City Libraries.

Images, eqnz.chch.2010

Photos taken at the Lyttelton Community briefing held on March 7 2011 following the magnitude 6.3 earthquake on 22 February 2011. File Ref: CCL-2011-03-07-Lyttelton-Community-Briefing-P1110619 From the collection of Christchurch City Libraries.

Images, eqnz.chch.2010

Photos taken at the Lyttelton Community briefing held on March 7 2011 following the magnitude 6.3 earthquake on 22 February 2011. File Ref: CCL-2011-03-07-Lyttelton-Community-Briefing-P1110621 From the collection of Christchurch City Libraries.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

Time stands still on the Science Museum clock tower as a poignant reminder of the moment the trembler struck Christchurch in the early hours of Saturday 4 September 2010.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

Time stands still on the Science Museum clock tower as a poignant reminder of the moment the trembler struck Christchurch in the early hours of Saturday 4 September 2010.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

The quake-damaged facade of the Baptist Church at the Kilmore Street / Madras Street intersection being propped up while repairs are in progress.

Images, eqnz.chch.2010

Time stands still on the Science Museum clock tower as a poignant reminder of the moment the trembler struck Christchurch in the early hours of Saturday 4 September 2010.

Research papers, University of Canterbury Library

On Tuesday 22 February 2011, a 6.3 magnitude earthquake struck Christchurch, New Zealand’s second largest city. The ‘earthquake’ was in fact an aftershock to an earlier 7.1 magnitude earthquake that had occurred on Saturday 4 September 2010. There were a number of key differences between the two events that meant they had dramatically different results for Christchurch and its inhabitants. The 22 February 2011 event resulted in one of New Zealand’s worst natural disasters on record, with 185 fatalities occurring and hundreds more being injured. In addition, a large number of buildings either collapsed or were damaged to the point where they needed to be totally demolished. Since the initial earthquake in September 2010, a large amount of building-related research has been initiated in New Zealand to investigate the impact of the series of seismic events – the major focus of these research projects has been on seismic, structural and geotechnical engineering matters. One project, however, conducted jointly by the University of Canterbury, the Fire Protection Association of New Zealand and BRANZ, has focused on the performance of fire protection systems in the earthquakes and the effectiveness of the systems in the event of post-earthquake fires occurring. Fortunately, very few fires actually broke out following the series of earthquake events in Christchurch, but fire after earthquakes still has significant implications for the built environment in New Zealand, and the collaborative research has provided some invaluable insight into the potential threat posed by post-earthquake fires in buildings. As well as summarising the damage caused to fire protection systems, this paper discusses the flow-on effect for designing structures to withstand post-earthquake fires. One of the underlying issues that will be explored is the existing regulatory framework in New Zealand whereby structural earthquake design and structural design for fire are treated as discrete design scenarios.

Research papers, University of Canterbury Library

This study explicitly investigates uncertainties in physics-based ground motion simulation validation for earthquakes in the Canterbury region. The simulations utilise the Graves and Pitarka (2015) hybrid methodology, with separately quantified parametric uncertainties in the comprehensive physics and simplified physics components of the model. The study is limited to the simulation of 148 small magnitude (Mw 3.5 – 5) earthquakes, with a point source approximation for the source rupture representations, which also enables a focus on a small number of relevant uncertainties. The parametric uncertainties under consideration were selected through sensitivity analysis, and specifically include: magnitude, Brune stress parameter and high frequency rupture velocity. Twenty Monte Carlo realisations were used to sample parameter uncertainties for each of the 148 events. Residuals associated with the following intensity measures: spectral acceleration, peak ground velocity, arias intensity and significant duration, were ascertained. Using these residuals, validation was performed through assessment of systematic biases in site and source terms from mixed-effects regression. Based on the results to date, initial standard deviation recommendations for parameter uncertainties, based on the Canterbury simulations have been obtained. This work ultimately provides an initial step toward explicit incorporation of modelling uncertainty in simulated ground motion predictions for future events, which will improve the use of simulation models in seismic hazard analysis. We plan to subsequently assess uncertainties for larger magnitude events with more complex ruptures, and events across a larger geographic region, as well as uncertainties due to path attenuation, site effects, and more general model epistemic uncertainties.

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".

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".

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. Anna Lipsham begins the clean up at Ashton, Wheelans and Hegan in Kaiapoi. Lipsham empties dirt from the building into a large fissure in the road".

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. Anna Lipsham begins the clean up at Ashton, Wheelans and Hegan in Kaiapoi. Lipsham empties dirt from the building into a large fissure in the road".

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. Warren Lipsham begins the clean up at Ashton, Wheelans and Hegan in Kaiapoi. Lipsham empties dirt from the building into a large fissure in the road".