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Images, Alexander Turnbull Library

Cartoons about political and social issues in New Zealand and overseas. The cartoon has the words 'Tsunami Warning cancelled' in the centre. Above are the words 'The end is nigh... insurance running out! No more cover!' Below the word 'cancelled' are the words 'We have reinsurance!' Context - Civil Defence has cancelled a tsunami warning after a 7.8 magnitude earthquake struck off the Kermadec Islands this morning (7 July 2011) The tsunami image is used to illustrate the problems that could arise from lack of insurance in Christchurch. When their policies run out on 30 June Earthquake-hit Christchurch and Waimakariri councils are in danger of having no property insurance because as the CEO of Civic Assurance, which insures most councils, says, 'the company cannot buy reinsurance'. There was also a potential problem for home-owners when AMI Insurance, the largest insurer of homes in Christchurch, was threatening insolvency. However, AMI has announced that it has re-insurance cover for earthquakes and other natural disasters from tomorrow (1 July 2011) for the next year. The Government feared AMI Insurance's directors would wind up the company affecting a huge section of New Zealand's insurance market and derail the reconstruction of Christchurch, official documents confirm. AMI said it had doubled its cover for the year to June 2012 after three large quakes in the year to June 2011. (Stuff 30 June 2011) Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The word 'CANTERBURY' is printed in large letters on the cartoon in the region's colours of red and black stripes. The 'CAN' part of the name is in larger print and is above the rest of the word. Context is 22 February 2011 earthquake in Christchurch. The cartoon refers to reports of courage, generosity and 'can do' attitude of the people. Colour and black and white versions of this cartoon are available Quantity: 2 digital cartoon(s).

Research papers, University of Canterbury Library

This dissertation addresses several fundamental and applied aspects of ground motion selection for seismic response analyses. In particular, the following topics are addressed: the theory and application of ground motion selection for scenario earthquake ruptures; the consideration of causal parameter bounds in ground motion selection; ground motion selection in the near-fault region where directivity effect is significant; and methodologies for epistemic uncertainty consideration and propagation in the context of ground motion selection and seismic performance assessment. The paragraphs below outline each contribution in more detail. A scenario-based ground motion selection method is presented which considers the joint distribution of multiple intensity measure (IM) types based on the generalised conditional intensity measure (GCIM) methodology (Bradley, 2010b, 2012c). The ground motion selection algorithm is based on generating realisations of the considered IM distributions for a specific rupture scenario and then finding the prospective ground motions which best fit the realisations using an optimal amplitude scaling factor. In addition, using different rupture scenarios and site conditions, two important aspects of the GCIM methodology are scrutinised: (i) different weight vectors for the various IMs considered; and (ii) quantifying the importance of replicate selections for ensembles with different numbers of desired ground motions. As an application of the developed scenario-based ground motion selection method, ground motion ensembles are selected to represent several major earthquake scenarios in New Zealand that pose a significant seismic hazard, namely, Alpine, Hope and Porters Pass ruptures for Christchurch city; and Wellington, Ohariu, and Wairarapa ruptures for Wellington city. A rigorous basis is developed, and sensitivity analyses performed, for the consideration of bounds on causal parameters (e.g., magnitude, source-to-site distance, and site condition) for ground motion selection. The effect of causal parameter bound selection on both the number of available prospective ground motions from an initial empirical as-recorded database, and the statistical properties of IMs of selected ground motions are examined. It is also demonstrated that using causal parameter bounds is not a reliable approach to implicitly account for ground motion duration and cumulative effects when selection is based on only spectral acceleration (SA) ordinates. Specific causal parameter bounding criteria are recommended for general use as a ‘default’ bounding criterion with possible adjustments from the analyst based on problem-specific preferences. An approach is presented to consider the forward directivity effects in seismic hazard analysis, which does not separate the hazard calculations for pulse-like and non-pulse-like ground motions. Also, the ability of ground motion selection methods to appropriately select records containing forward directivity pulse motions in the near-fault region is examined. Particular attention is given to ground motion selection which is explicitly based on ground motion IMs, including SA, duration, and cumulative measures; rather than a focus on implicit parameters (i.e., distance, and pulse or non-pulse classifications) that are conventionally used to heuristically distinguish between the near-fault and far-field records. No ad hoc criteria, in terms of the number of directivity ground motions and their pulse periods, are enforced for selecting pulse-like records. Example applications are presented with different rupture characteristics, source-to-site geometry, and site conditions. It is advocated that the selection of ground motions in the near-fault region based on IM properties alone is preferred to that in which the proportion of pulse-like motions and their pulse periods are specified a priori as strict criteria for ground motion selection. Three methods are presented to propagate the effect of seismic hazard and ground motion selection epistemic uncertainties to seismic performance metrics. These methods differ in their level of rigor considered to propagate the epistemic uncertainty in the conditional distribution of IMs utilised in ground motion selection, selected ground motion ensembles, and the number of nonlinear response history analyses performed to obtain the distribution of engineering demand parameters. These methods are compared for an example site where it is observed that, for seismic demand levels below the collapse limit, epistemic uncertainty in ground motion selection is a smaller uncertainty contributor relative to the uncertainty in the seismic hazard itself. In contrast, uncertainty in ground motion selection process increases the uncertainty in the seismic demand hazard for near-collapse demand levels.

Research papers, The University of Auckland Library

Following a damaging earthquake, the immediate emergency response is focused on individual collapsed buildings or other "hotspots" rather than the overall state of damage. This lack of attention to the global damage condition of the affected region can lead to the reporting of misinformation and generate confusion, causing difficulties when attempting to determine the level of postdisaster resources required. A pre-planned building damage survey based on the transect method is recommended as a simple tool to generate an estimate of the overall level of building damage in a city or region. A methodology for such a transect survey is suggested, and an example of a similar survey conducted in Christchurch, New Zealand, following the 22 February 2011 earthquake is presented. The transect was found to give suitably accurate estimates of building damage at a time when information was keenly sought by government authorities and the general public. VoR - Version of Record

Images, Alexander Turnbull Library

The cartoon shows the 'CCC Office' (Christchurch City Council) as a small ramshackle wooden building in a desert; bits of animal skeleton lie around and there are saguaro cactus and tumbleweed. A cowboy has arrived and asks 'So... Can I speak to the Deputy, Deputy, Deputy, Assistant Sheriff?' Context - A reference to layers of officialdom in Christchurch as the city struggles to rebuild itself as well as many councillors being away on holiday while the quake problems continue. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The cartoon shows rubble and ruined buildings after the Canterbury earthquake of 4th September 2010. Rats representing 'looters' run over the buildings taking advantage as do cockroaches representing 'politics'. Refers to a certain amount of looting but also the high profiles during the aftermath of Mayor Bob Parker with local body elections only a few weeks away and PM John Key in particular. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

At 4.35am on Saturday 4 September 2010, a magnitude 7.1 earthquake struck near the township of Darfield in Canterbury leading to widespread damage in Christchurch and the wider central Canterbury region. Though it was reported no lives were lost, that was not entirely correct. Over 3,000 animals perished as a result of the earthquake and 99% of these deaths would have been avoidable if appropriate mitigation measures had been in place. Deaths were predominantly due to zoological vulnerability of birds in captive production farms. Other problems included lack of provision of animal welfare at evacuation centres, issues associated with multiple lost and found pet services, evacuation failure due to pet separation and stress impact on dairy herds and associated milk production. The Canterbury Earthquake has highlighted concerns over a lack of animal emergency welfare planning and capacity in New Zealand, an issue that is being progressed by the National Animal Welfare Emergency Management Group. As animal emergency management becomes better understood by emergency management and veterinary professionals, it is more likely that both sectors will have greater demands placed upon them by national guidelines and community expectations to ensure provisions are made to afford protection of animals in times of disaster. A subsequent and more devastating earthquake struck the region on Monday 22 February 2011; this article however is primarily focused on the events pertaining to the September 4 event.

Audio, Radio New Zealand

More snow expected in Southland as region starts to mop up, United Future leader questions stability of Act, Seismologists say aftershocks tailing off for Canterbury, Questions raised over earthquake victims insurance, Gunmen attack tourists in Delhi shooting and Farm land drops two-thirds in value in one year.

Research papers, University of Canterbury Library

There has not been substantial research conducted in the area of fraud and natural disasters. Therefore, this study sought to examine the perceptions of Canterbury residents toward the recovery process following the September 2010 and February 2011 earthquakes and whether residents felt as though contractor fraud occurs in Canterbury. A questionnaire was developed to gauge information about Canterbury residents’ self-reports involving the earthquakes, specific contractors involved, parties involved with the recovery process in general, and demographic information. Participants included a total of 213 residents from the Canterbury region who had been involved with contractors and/or insurance companies due to the recovery process. Results indicated that a high percentage of the participants were not satisfied with the recovery process and that almost half of the participants reported feeling scammed by contractors in Canterbury after the 2010 and 2011 earthquakes. Moreover, the results indicate that participants neither agreed with the assessments made about their property losses nor the plans made to recover their properties. In many cases, participants felt pressured and even reluctant to accept these assessments and/or plans. The present study does not seek to explain why contractor fraud exists or what motivates scammers. Conversely, it attempts to demonstrate the perceptions of contractor fraud and satisfaction that have taken place in the aftermath of the Canterbury earthquakes.

Research papers, University of Canterbury Library

Field surveys and experimental studies have shown that light steel or timber framed plasterboard partition walls are particularly vulnerable to earthquake damage prompting the overarching objective of this research, which is to further the development of low damage seismic systems for non-structural partition walls in order to facilitate their adoption by industry to assist with reducing the losses associated with the maintenance and repair cost of buildings across their design life. In particular, this study focused on the behaviour of steel-framed partition walls systems with novel detailing that aim to be “low-damage” designed according to common practice for walls used in commercial and institutional buildings in New Zealand. This objective was investigated by (1) investigating the performance of a flexible track system proposed by researchers and industry by experimental testing of full-scale specimens; (2) investigating the performance of the seismic gap partition wall systems proposed in a number of studies, further developed in this study with input from industry, by experimental testing of full-scale specimens; and (3) investigating the potential implications of using these systems compared with traditionally detailed partition wall systems within multi-storey buildings using the Performance Based Earthquake Engineering loss assessment methodology. Three full-scale testing frames were designed in order to replicate, under controlled laboratory conditions, the effects of seismic shaking on partition walls within multi-storey buildings by the application of quasi-static uni-directional cyclic loading imposing an inter-storey drift. The typical configuration for test specimens was selected to be a unique “y-shape”, including one angled return wall, with typical dimensions of approximately 2400 mm along the main wall and 600 mm along (approximately) the returns walls with a height of 2405 mm from floor to ceiling. The specimens were aligned within test frames at an oblique angle to the direction of loading in order to investigate bi- directional effects. Three wall specimens with flexible track detailing, two identical plane specimens and the third including a doorway, were tested. The detailing involved removing top track anchors within the proximity of wall intersections, thus allowing the tracks to ‘bow’ out at these locations. Although the top track anchors were specified to be removed the proximity of wall intersections, a construction error was made whereby a single top track slab to concrete anchor was left in at the three-way wall junction. Despite this error, the experimental testing was deemed worthwhile since such errors will also occur in practice and because the behaviour of the wall can be examined with this fixing in mind. The specimens also included an acoustic/fire sealant at the top lining to floor boundary. In addition to providing drift capacities, the force-displacement behaviour is also reported, the dissipated energy was computed, and the parameters of the Wayne-Stewart hysteretic model were fitted to the results. The specimen with the door opening behaved significantly different to the plane specimens: damage to the doorway specimen began as cracking of the wallboard propagating from the corners of the doorway following which the L- and Y- shaped junctions behaved independently, whereas damage to the plane specimens began as cracking of the wallboard at the top of the L-junction and wall system deformed as a single unit. The results suggest that bi-directional behaviour is important even if its impact cannot be directly quantified by the experiments conducted. Damage to sealant implies that the bond between plasterboard and sealant is important for its seismic performance. Careful quality control is advised as defects in the bond may significantly impact its ability to withstand seismic movement. Two specimens with seismic gap detailing were tested: a steel stud specimen and a timber stud specimen. Observed drift capacities were significantly greater than traditional plasterboard partition systems. Equations were used to predict the drift at which damage state 1 (DS1) and damage state 2 (DS2) would initiate. The equation used to estimate the drift at the onset of DS1 accurately predicted the onset of plaster cracking but overestimated the drift at which the gap filling material was damaged. The equation used to predict the onset of DS2 provided a lower bound for both specimens and also when used to predict results of previous experimental tests on seismic gap systems. The gap-filling material reduced the drift at the onset of DS1, however, it had a beneficial effect on the re-centring behaviour of the linings. Out-of-plane displacements and return wall configuration did not appear to significantly impact the onset of plaster cracking in the specimens. A loss assessment according to the PBEE methodology was conducted on four steel MRF case study buildings: (1) a 4-storey building designed for the Christchurch region, (2) a 4-storey building designed for the Wellington region, (3) a 12-storey building designed for the Christchurch region, and (4) a 12- storey building designed for the Wellington region. The fragility parameters for a traditional partition system, the flexible track partition system, and the seismic gap steel stud and timber stud partition systems were included within the loss assessment. The order (lowest to highest) of each system in terms of the expected annual losses of each building when incorporating the system was, (1) the seismic gap timber stud system, (2) the seismic gap steel stud system, (3) the traditional/baseline system, and (4) the flexible track system. For the seismic gap timber stud system, which incurred the greatest reduction in expected annual losses for each case study building, the reduction in expected annual losses in comparison to the losses found when using the traditional system ranged from a 5% to a 30% reduction. This reinforces the fact that while there is a benefit to the using low damage partition systems in each building the extent of reduction in expected annual losses is significantly dependent on the particular building design and its location. The flexible track specimens had larger repair costs at small hazard levels compared to the traditional system but smaller repair costs at larger hazard levels. However, the resulting expected annual losses for the flexible track system was higher than the traditional system which reinforces findings from past studies which observed that the greatest contribution to expected annual losses arises from low to moderate intensity shaking seismic events (low hazard levels).

Research papers, University of Canterbury Library

Oblique-convergent plate collision between the Pacific and Australian plates across the South Island has resulted in shallow, upper crustal earthquake activity and ground surface deformation. In particular the Porters Pass - Amberley Fault Zone displays a complex hybrid zone of anastomosing dextral strike-slip and thrust/reverse faulting which includes the thrust/reverse Lees Valley Fault Zone and associated basin deformation. There is a knowledge gap with respect to the paleoseismicity of many of the faults in this region including the Lees Valley Fault Zone. This study aimed to investigate the earthquake history of the fault at a selected location and the structural and geomorphic development of the Lees Valley Fault Zone and eastern rangefront. This was investigated through extensive structural and geomorphic mapping, GPS field surveying, vertical aerial photo interpretation, analysis of Digital Elevation Models, paleoseismic trenching and optically stimulated luminescence dating. This thesis used a published model for tectonic geomorphology development of mountain rangefronts to understand the development of Lees Valley. Rangefront geomorphology is investigated through analysis of features such as rangefront sinuosity and faceted spurs and indicates the recently active and episodic nature of the uplifted rangefront. Analysis of fault discontinuity, fault splays, distribution of displacement, fault deformation zone and limited exposure of bedrock provided insight into the complex structure of the fault zone. These observations revealed preserved, earlier rangefronts, abandoned and uplifted within the eastern ranges, indicating a basinward shift in focus of faulting and an imbricate thrust wedge development propagating into the footwall of the fault zone and along the eastern ranges of Lees Valley. Fault scarp deformation analysis indicated multiple events have produced the deformation present preserved by the active fault trace in the northern valley. Vertical deformation along this scarp varied with a maximum of 11.5 m and an average of 5 m. Field mapping revealed fan surfaces of various ages have been offset and deformed, likely during the Holocene, based on expected relative surface ages. Geomorphic and structural mapping highlighted the effect of cross-cutting and inherited structures on the Lees Valley Fault, resulting in a step-over development in the centre of the eastern range-bounding trace. Paleoseismic trenching provided evidence of at least two earthquakes, which were constrained to post 21.6 ± 2.3 ka by optically stimulated luminescence dating. Single event displacements (1.48 ± 0.08 m), surface rupture earthquake magnitudes (Mw 6.7 ± 0.1, with potential to produce ≥ 7.0), and a minimum recurrence interval (3.6 ± 0.3 ka) indicated the Lees Valley Fault is an active structure capable of producing significant earthquake events. Results from this study indicate that the Lees Valley Fault Zone accommodates an important component of the Porters Pass - Amberley Fault Zone deformation and confirms the fault as a source of potentially damaging, peak ground accelerations in the Canterbury region. Remnants of previous rangefronts indicate a thrust wedge development of the Lees Valley Fault Zone and associated ranges that can potentially be used as a model of development for other thrust-fault bounded basins.

Images, Alexander Turnbull Library

Shows a helicopter spray painting Christchurch with the Canterbury colours of black and red. Someone in the helicopter yells that 'it's gotta be better than tint of TC3'. Context: Probably refers to the apology by Earthquake Recovery Minister Gerry Brownlee for offending Christchurch's TC3 residents after saying he was 'sick and tired' of their moaning. TC3 means 'technical category 3'. Land classified TC3 is the mostly badly quake-damaged considered economically repairable. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

This paper presents a seismic velocity model of Canterbury, New Zealand based on 3D geologic surfaces and velocities from a range of data sources. The model provides the 3D crustal structure in the region at multiple length scales for seismic wave propagation simulations, such as broadband ground motion and shallow site response analyses related to understanding the ground motions and site responses during the 2010- 2011 Canterbury earthquakes. Pre-Quaternary geologic horizons are calculated based on the reinterpretation of a comprehensive network of seismic reflection surveys from seven different campaigns over the past 50 years, as well as point constraints across an array of petroleum industry drill holes. Particular attention is given to a detailed representation of Quaternary stratigraphy, representing shallow (z<250m) near-surface layers in the model. Seismic velocities are obtained from seismic reflection processing (for Vp) and also recently performed active and passive surface wave analyses (for Vs). Over 1,700 water wells in the region are used to constrain the complex inter-bedded Quaternary stratigraphy (gravels, sands, silts, organics etc.) near the coastline, including beneath urban Christchurch, which has resulted from fluvial deposition and marine regression and transgression. For the near-surface Springston and Christchurch Formations in the Christchurch urban area (z<50m), high-spatial resolution seismic velocities (including Vs30 ) were obtained from over 13,000 cone penetration tests combined with a recently developed CPT-Vs correlation.

Research papers, University of Canterbury Library

This paper summarizes the development of a region-wide surficial shear wave velocity model based on the combination of the large high-spatial-density database of cone penetration test (CPT) logs in and around Christchurch, New Zealand and a recently-developed Christchurch-specific empirical correlation between soil shear wave velocity and CPT. The ongoing development of this near-surface shear wave velocity model has applications for site characterization efforts via the development of maps of time-averaged shear wave velocities over specific depths, and the identification of regional similarities and differences in soil shear stiffness.

Images, Alexander Turnbull Library

Text across the top of the cartoon reads 'When the luck ran out' and shows a disintegrating building that includes two dice with a skull and crossbone on one facet. Context - On 22 February 2011 at 12:51 pm (NZDT), Christchurch experienced a major magnitude 6.3 earthquake, which resulted in severe damage and many casualties. A National State of Emergency has been declared. This followed on from an original magnitude 7.1 earthquake on 4 September 2010 which did far less damage and in which no-one died. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

A man sits at a table reading a C.C.C. (Christchurch City Council) report with the title 'Where your rates go!' He says 'Rubbish collection sewer roads squanderings bail outs' Context - After the Christchurch earthquake of 4 September 2010 rates have been of particular concern to residents which means people are sensitive to any possibility of squandering. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

A couple are woken by loud thuds, rumbles and crashes. A woman leaps up in bed in a panic saying 'My God! Not another aftershock!' Her husband says 'Nah! Another flamin' haka!' A newspaper on the bed has a headline that reads 'World Cup in full swing.' Context: The World Cup began on Friday 9th September and ends on 23 October. People in Christchurch are still regularly jolted by aftershocks to the earthquakes of September 2010 and February and June 2011. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The title reads 'Greener square for Christchurch?..' The cartoon depicts the city centre in Christchurch entirely covered with green and there are cows wandering by the stream as well as grazing on the tops of buildings. A man at the top of the green cathedral says 'I can see it really growing on me!' Context: This is a reference to the draft Central City plan under which the Central City will be greener and more attractive. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

Shows an egg that represents '2012' with a chick beginning to peck its way out. In the background storms rage. Someone hopes that it will 'be softer and fuzzier than the last one!' Context: Refers to the difficulties and disasters of 2011 in New Zealand. Christchurch earthquakes and aftershocks continue with complicating rebuilding and insurance issues, the wreck of the Rena, and various weather events and political issues. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

A man struggles to hold upright a rigid and obstinate man who is shaking like an earthquake. The man pushing says 'That's NOT what we meant by quake strengthening Aaron!' Context: Aaron Gilmore is a councillor, a new councillor, and has been bucking the trend when it comes to voting for the CEO Tony Marryatt who is tied up with CERA, the canterbury earthquake authority, by publicly making his personal views known to the public on radio etc before the voting has been cast. Councillors are meant to present an unbiased facade when it comes to voting. Gilmore was talking to the media and in obvious support of Marryatt....the result being that there was pressure on Gilmore to abstain from voting and stand down from the process. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

Text across the top of the cartoon reads 'Greener pastures for red zone residents?... A new subdivision named 'Quakehaven' has streets named 'Wobble Way', 'Poopong Parade', 'Turd Tce.', 'Liquefaction Lane' etc. One of a couple visiting the new area says 'I've got a bad feeling about this new subdivision!' Context - Housing after the Christchurch earthquakes. After the first Land Report was delivered on 23rd June people whose houses were in the Red Zone had their properties bought up by the government and now have to move to new subdivisions. The suggestion in the cartoon is that the subdivisions may not be on safe ground. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The title reads 'Ellerslie Flower Show to return to Christchurch...' Below are nine cameos showing 'sinking violets', 'cracked chrysanthemums', 'pooey perrenials', 'rubble roses', 'portaloo poppies', 'munted marigolds', 'knackered natives', the 'lily of liquefaction' and 'wearable exhibits' which shows a woman wearing a toilet roll and carrying a spade. Context: The next Ellerslie International Flower Show will be staged in North Hagley Park from 7-11 March 2012. Following cancellation of the 2011 Show after the 22 February earthquake, Christchurch City Council has confirmed that the citys premier garden show will go ahead next year in the same venue as previous years. (http://www.ellerslieflowershow.co.nz/) Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

A huge fist representing 'quakes', that is wearing a boxing glove, thumps a man who represents 'CHCH' (Christchurch) 'WHUMP! WHUMP! WHUMP!' The man is knocked out. Context - Magnitude 6.0 and 5.5 earthquakes rocked Christchurch again at 1pm and 2.20pm on 13th June 2011. These quakes follow the first earthquake on September 4th 2010 and the second on February 22nd 2011. (www.stuff.co.nz, 13 June 2011) Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The title reads 'Shipping container shopping for Merivale?.. The cartoon shows a row of shops that have been created from containers. An oil slick seeps from one of them. Someone in 'Chez Merivale' says 'Nice idea darling. But did they have to use the Rena's containers?' Context: Refers to the container ship 'Rena' which is grounded on the Astrolabe Reef off the Bay of Plenty and threatens to become a disaster of huge proportions as oil spews into the sea. Modified shipping containers have been put in place in the suburb of Merivale to replace broken shops. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

The Mw 7.8 Kaikōura earthquake ruptured ~200 km at the ground surface across the New Zealand plate boundary zone in the northern South Island. This study was conducted in an area of ~600 km2 in the epicentral region where the faults comprise two main non-coplanar sets that strike E-NE and NNE-NW with mainly steep dips (60о-80°). Analysis of the surface rupture using field and LiDAR data provides new information on the dimensions, geometries and kinematics of these faults which was not previously available from pre-earthquake active faults or bedrock structure. The more northerly striking fault set are sub-parallel to basement bedding and accommodated predominantly left-lateral reverse slip with net slips of ~1 and ~5 m for the Stone Jug and Leader faults, respectively. The E-NE striking Conway-Charwell and The Humps faults accrued right-lateral to oblique reverse with net slips of ~2 and ~3 m, respectively. The faults form a hard-linked system dominated by kinematics consistent with the ~260° trend of the relative plate motion vector and the transpressional structures recorded across the plate boundary in the NE South Island. Interaction and intersection of the main fault sets facilitated propagation of the earthquake and transfer of slip northwards across the plate boundary zone.

Research papers, University of Canterbury Library

his poster presents the ongoing development of a 3D Canterbury seismic velocity model which will be used in physics-based hybrid broadband ground motion simulation of the 2010-2011 Canterbury earthquakes. Velocity models must sufficiently represent critical aspects of the crustal structure over multiple length scales which will influence the results of the simulations. As a result, numerous sources of data are utilized in order to provide adequate resolution where necessary. Figure 2: (a) Seismic reflection line showing P-wave velocities and significant geologic horizons (Barnes et al. 2011), and (b) Shear wave profiles at 10 locations (Stokoe et al. 2013). Figure 4: Cross sections of the current version of the Canterbury velocity model to depths of 10km as shown in Figure 1: (a) at a constant latitude value of -43.6˚, and (b) at a constant longitude value of 172.64˚. 3. Ground Surface and Geologic Horizon Models Figure 3: (a) Ground surface model derived from numerous available digital elevation models, and (b) Base of the Quaternary sediments derived from structural contours and seismic reflection line elevations. The Canterbury region has a unique and complex geology which likely has a significant impact on strong ground motions, in particular the deep and loose deposits of the Canterbury basin. The Canterbury basin has several implications on seismic wave phenomena such as long period ground motion amplification and wave guide effects. Using a realistic 3D seismic velocity model in physics-based ground motion simulation will implicitly account for such effects and the resultant simulated ground motions can be studied to gain a fundamental understanding of the salient ground motion phenomena which occurred during the Canterbury earthquakes, and the potential for repeat occurrences in the Canterbury region. Figure 1 shows the current model domain as a rectangular area between Lat=[-43.2˚,-44.0˚], and Lon=[171.5˚,173.0˚]. This essentially spans the area between the foot of the Southern Alps in the North West to Banks Peninsula in the East. Currently the model extends to a depth of 50km below sea level.