Dissertations / Theses: 'Earthquake zones New Zealand'

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Walsh, David Leonard. "Directional statistics, Bayesian methods of earthquake focal mechanism estimation, and their application to New Zealand seismicity data : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Master of Science in Statistics /." ResearchArchive@Victoria e-Thesis, 2008. http://hdl.handle.net/10063/350.

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Robinson, Thomas Russell. "Assessment of coseismic landsliding from an Alpine fault earthquake scenario, New Zealand." Thesis, University of Canterbury. Department of Geological Sciences, 2014. http://hdl.handle.net/10092/10029.

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Disasters can occur without warning and severely test society’s capacity to cope, significantly altering the relationship between society and the built and natural environments. The scale of a disaster is a direct function of the pre-event actions and decisions taken by society. Poor pre-event planning is a major contributor to disaster, while effective pre-event planning can substantially reduce, and perhaps even avoid, the disaster. Developing and undertaking effective planning is therefore a vital component of disaster risk management in order to achieve meaningful societal resilience. Disaster scenarios present arguably the best and most effective basis to plan an effective emergency response to future disasters. For effective emergency response planning, disaster scenarios must be as realistic as possible. Yet for disasters resulting from natural hazards, intricately linked secondary hazards and effects make development of realistic scenarios difficult. This is specially true for large earthquakes in mountainous terrain. The primary aim of this thesis is therefore to establish a detailed and realistic disaster scenario for a Mw8.0 earthquake on the plate boundary Alpine fault in the South Island of New Zealand with specific emphasis on secondary effects. Geologic evidence of re-historic earthquakes on this fault suggest widespread and large-scale landsliding has resulted throughout the Southern Alps, yet, currently, no attempts to quantitatively model this landsliding have been undertaken. This thesis therefore provides a first attempt at quantitative assessments of the likely scale and impacts of landsliding from a future Mw8.0 Alpine fault earthquake. Modelling coseismic landsliding in regions lacking historic inventories and geotechnical data (e.g. New Zealand) is challenging. The regional factors that control the spatial distribution of landsliding however, are shown herein to be similar across different environments. Observations from the 1994 Northridge, 1999 Chi-Chi, and 2008 Wenchuan earthquakes identified MM intensity, slope angle and position, and distance from active faults and streams as factors controlling the spatial distribution of landsliding. Using fuzzy logic in GIS, these factors are able to successfully model the spatial distribution of coseismic landsliding from both the 2003 and 2009 Fiordland earthquakes in New Zealand. This method can therefore be applied to estimate the scale of landsliding from scenario earthquakes such as an Alpine fault event. Applied to an Mw8.0 Alpine fault earthquake, this suggests that coseismic landsliding could affect an area >50,000 km2 with likely between 40,000 and 110,000 landslides occurring. Between 1,400 and 4,000 of these are expected to present a major hazard. The environmental impacts from this landsliding would be severe, particularly in west-draining river catchments, and sediment supply to rivers in some catchments may exceed 50 years of background rates. Up to 2 km3 of total landslide debris is expected, and this will have serious and long-term consequences. Fluvial remobilisation of this material could result in average aggradation depths on active alluvial fans and floodplains of 1 m, with maximum depths substantially larger. This is of particular concern to the agriculture industry, which relies on the fertile soils on many of the active alluvial fans affected. This thesis also investigated the potential impacts from such landsliding on critical infrastructure. The State Highway and electrical transmission networks are shown to be particularly exposed. Up to 2,000 wooden pole and 30 steel pylon supports for the transmission network are highly exposed, resulting in >23,000 people in the West Coast region being exposed to power loss. At least 240 km of road also has high exposure, primarily on SH6 between Hokitika and Haast, and on Arthur’s and Lewis Passes. More than 2,750 local residents in Westland District are exposed to isolation by road as a result. The Grey River valley region is identified as the most critical section of the State Highway network and pre-event mitigation is strongly recommended to ensure the road and bridges here can withstand strong shaking and liquefaction hazards. If this section of the network can remain functional post-earthquake, the emergency response could be based out of Wellington using Nelson as a forward operating base with direct road access to some of the worst-affected locations. However, loss of functionality of this section of road will result in >24,000 people becoming isolated across almost the entire West Coast region. This thesis demonstrates the importance and potential value of pre-event emergency response planning, both for the South Island community for an Alpine fault earthquake, and globally for all such hazards. The case study presented demonstrates that realistic estimates of potential coseismic landsliding and its impacts are possible, and the methods developed herein can be applied to other large mountainous earthquakes. A model for developing disaster scenarios in collaboration with a wide range of societal groups is presented and shown to be an effective method for emergency response planning, and is applicable to any hazard and location globally. This thesis is therefore a significant contribution towards understanding mountainous earthquake hazards and emergency response planning.

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Boulton, Carolyn Jeanne. "Experimental Investigation of Gouges and Cataclasites, Alpine Fault, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2013. http://hdl.handle.net/10092/8917.

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The upper 8-12 km of the Alpine Fault, South Island, New Zealand, accommodates relative Australia-Pacific plate boundary motion through coseismic slip accompanying large-magnitude earthquakes. Earthquakes occur due to frictional instabilities on faults, and their nucleation, propagation, and arrest is governed by tectonic forces and fault zone properties. A multi-disciplinary dataset is presented on the lithological, microstructural, mineralogical, geochemical, hydrological, and frictional properties of Alpine Fault rocks collected from natural fault exposures and from Deep Fault Drilling Project (DFDP-1) drillcore. Results quantify and describe the physical and chemical processes that affect seismicity and slip accommodation. Oblique dextral motion on the central Alpine Fault in the last 5-8 Myr has exhumed garnet-oligoclase facies mylonitic fault rocks from depths of up to 35 km. During the last phase of exhumation, brittle deformation of these mylonites, accompanied by fluid infiltration, has resulted in complex mineralogical and lithological variations in the fault rocks. Petrophysical, geochemical, and lithological data reveal that the fault comprises a central alteration zone of protocataclasites, foliated and nonfoliated cataclasites, and fault gouges bounded by a damage zone containing fractured ultramylonites and mylonites. Mineralogical results suggest that at least two stages of chemical alteration have occurred. At, or near, the brittle-to-ductile transition (c. >320 °C), metasomatic alteration reactions resulted in plagioclase and feldspar replacement by muscovite and sausserite, and biotite (phlogopite), hornblende (actinolite) and/or epidote replacement by chlorite (clinochlore). At lower temperatures (c. >120°C), primary minerals were altered to kaolinite, smectite and pyrite, or kaolinite, smectite, Fe-hydroxide (goethite) and carbonate, depending on redox conditions. Ultramylonites, nonfoliated and foliated cataclasites, and gouges in the hanging wall and footwall contain the high-temperature phyllosilicates chlorite and white mica (muscovite/illite). Brown principal slip zone (PSZ) gouges contain the low-temperature phyllosilicates kaolinite and smecite, and goethite and carbonate cements. The frictional and hydrological properties of saturated intact samples of central Alpine Fault surface-outcrop gouges and cataclasites were investigated in room temperature experiments conducted at 30-33 MPa effective normal stress (σn') using a double-direct shear configuration and controlled pore fluid pressure in a triaxial pressure vessel. Surface-outcrop samples from Gaunt Creek, location of DFDP-1, displayed, with increasing distance (up to 50 cm) from the contact with footwall fluvioglacial gravels: (1) an increase in fault normal permeability (k = 7.45 x 10⁻²⁰ m² to k = 1.15 x 10⁻¹⁶ m²), (2) a transition from frictionally weak (μ=0.44) fault gouge to frictionally strong (μ=0.50’0.55) cataclasite, (3) a change in friction rate dependence (a–b) from solely velocity strengthening to velocity strengthening and weakening, and (4) an increase in the rate of frictional healing. The frictional and hydrological properties of saturated intact samples of southern Alpine Fault surface-outcrop gouges were also investigated in room temperature double-direct shear experiments conducted at σn'= 6-31 MPa. Three complete cross-sections logged from outcrops of the southern Alpine Fault at Martyr River, McKenzie Creek, and Hokuri Creek show that dextral-normal slip is localized to a single 1-12 m-thick fault core comprising impermeable (k=10⁻²⁰ to 10⁻²² m²), frictionally weak (μ=0.12 – 0.37), velocity-strengthening, illite-chlorite and trioctahedral smectite (saponite)-chlorite-lizardite fault gouges. In low velocity room temperature experiments, Alpine Fault gouges tested have behaviours associated with aseismic creep. In a triaxial compression apparatus, the frictional properties of PSZ gouge samples recovered from DFDP-1 drillcore at 90 and 128 m depths were tested at temperatures up to T=350°C and effective normal stresses up to σn'=156 MPa to constrain the fault's strength and stability under conditions representative of the seismogenic crust. The chlorite/white mica-bearing DFDP-1A blue gouge is frictionally strong (μ=0.61–0.76) across a range of experimental conditions (T=70–350°C, σn'=31.2–156 MPa) and undergoes a stability transition from velocity strengthening to velocity weakening as T increases past 210°C, σn'=31.2–156 MPa. The coefficient of friction of smecite-bearing DFDP-1B brown gouge increases from μ=0.49 to μ=0.74 with increasing temperature and pressure (T=70–210°C, σn'=31.2–93.6 MPa) and it undergoes a transition from velocity strengthening to velocity weakening as T increases past 140°C, σn'=62.4 MPa. In low velocity hydrothermal experiments, Alpine Fault gouges have behaviours associated with potentially unstable, seismic slip at temperatures ≥140°C, depending on mineralogy. High-velocity (v=1 m/s), low normal stress (σn=1 MPa) friction experiments conducted on a rotary shear apparatus showed that the peak coefficient of friction (μp) of Alpine Fault cataclasites and fault gouges was consistently high (mean μp=0.69±0.06) in room-dry experiments. Variations in fault rock mineralogy and permeability were more apparent in experiments conducted with pore fluid, wherein the peak coefficient of friction of the cataclasites (mean μp=0.64±0.04) was higher than the fault gouges (mean μp=0.24±0.16). All fault rocks exhibited very low steady state coefficients of friction (μss) (room-dry mean μss=0.18±0.04; saturated mean μss=0.10±0.04). Three high-velocity experiments conducted on saturated smectite-bearing principal slip zone (PSZ) fault gouges had the lowest peak friction coefficients (μp=0.13-0.18), lowest steady state friction coefficients (μss=0.02-0.10), and lowest breakdown work values (WB=0.07-0.11 MJ/m²) of all the experiments performed. Lower strength (μ < c. 0.62) velocity-strengthening fault rocks comprising a realistically heterogeneous fault plane represent barrier(s) to rupture propagation. A wide range of gouges and cataclasites exhibited very low steady state friction coefficients in high-velocity friction experiments. However, earthquake rupture nucleation in frictionally strong (μ ≥ c. 0.62), velocity-weakening material provides the acceleration necessary to overcome the low-velocity rupture propagation barrier(s) posed by velocity-strengthening gouges and cataclasites. Mohr-Coulomb theory stipulates that sufficient shear stress must be resolved on the Alpine Fault, or pore fluid pressure must be sufficiently high, for earthquakes to nucleate in strong, unstable fault materials. A three-dimensional stress analysis was conducted using the average orientation of the central and southern Alpine Fault, the experimentally determined coefficient of friction of velocity-weakening DFDP-1A blue gouge, and the seismologically determined stress tensor and stress shape ratio(s). Results reveal that for a coefficient of friction of μ ≥ c. 0.62, the Alpine Fault is unfavourably oriented to severely misoriented for frictional slip.

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Idle, Julian Clifford. "The preparedness and response of the population of Lyttelton, New Zealand, and surrounding areas, for and to hazards." Thesis, University of Canterbury. Department of Geological Sciences, 2012. http://hdl.handle.net/10092/7245.

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Small, tight-knit communities, are complex to manage from outside during a disaster. The township of Lyttelton, New Zealand, and the communities of Corsair Bay, Cass Bay, and Rapaki to the east, are especially more so difficult due to the terrain that encloses them, which caused them to be cut-off from Christchurch, the largest city in the South Island, barely 10 km away, after the Mw 7.1 Darfield Earthquake and subsequent Canterbury Earthquake Sequence. Lyttelton has a very strong and deep-rooted community spirit that draws people to want to be a part of Lyttelton life. It is predominantly residential on the slopes, with retail space, service and light industry nestled near the harbour. It has heritage buildings stretching back to the very foundation of Canterbury yet hosts the largest, modern deep-water port for the region. This study contains two surveys: one circulated shortly before the Darfield Earthquake and one circulated in July 2011, after the Christchurch and Sumner Earthquakes. An analytical comparison of the participants’ household preparedness for disaster before the Darfield Earthquake and after the Christchurch and Sumner Earthquakes was performed. A population spatiotemporal distribution map was produced that shows the population in three-hourly increments over a week to inform exposure to vulnerability to natural hazards. The study went on to analyse the responses of the participants in the immediate period following the Chrsitchurch and Sumner Earthquakes, including their homeward and subsequent journeys, and the decision to evacuate or stay in their homes. Possible predictors to a decision to evacuate some or all members of the household were tested. The study also asked participants’ views on the events since September 2010 for analysis.

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Singh, Bina Aruna. "GIS based assessment of seismic risk for the Christchurch CBD and Mount Pleasant, New Zealand." Thesis, University of Canterbury. Geography, 2006. http://hdl.handle.net/10092/1302.

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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.

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Yetton, Mark D. "The probability and consequences of the next alpine fault earthquake, South Island, New Zealand." Thesis, University of Canterbury. Geology, 2000. http://hdl.handle.net/10092/6879.

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Detailed paleoseismic investigation of the Alpine Fault, South Island, New Zealand, has been undertaken at locations which bracket the central and north sections of the fault, between the Hokitika and Ahaura River. A total of seven trenches and pits have been excavated at four localities along approximately 75 kilometres of the fault. From these excavations a total of 16 radiocarbon dates provide age constraints on the timing of the most recent two earthquakes. This trenching demonstrates that the most recent rupture occurred after 1660 AD, and most probably around 1700 - 1750 AD. There is consistent evidence for this event in the trenches in the central section of the fault. The surface rupture has extended into the north section of the fault as far as the Haupiri River area, which is 25 km northeast of the Alpine Fault junction with the Hope Fault. An earlier event at around 1600 AD can be recognised throughout the study area, and this is the most recent event in the trench locations north of the Haupiri River. An updated record of landslide and aggradation terrace ages is consistent with two earthquakes over this period, but this does not significantly refine the estimates of their timing. However, the analysis of indigenous forest age in Westland and Buller reveals two periods of synchronous regional forest damage at 1625 ± 15 AD and 1715 ± 15 AD. I infer that these two episodes of forest damage correspond to the two earthquakes revealed in the trenches for this same time period. Analysis of growth rings in trees which are old enough to have survived these earthquakes indicates that the most recent event occurred in 1717 AD. The growth ring anomalies also indicate a northeast earthquake limit near the Haupiri River. The most recent 1717 AD event appears to have been a synchronous rupture for a distance of over 375 km, from Milford Sound in the south Westland section of the fault, northeast to the Haupiri River. Based on the forest disturbance record, the earlier earthquake at 1625 ± 15 AD had a rupture length of at least 250 km, but further work is required to determine the southwest and northeast limits of this event. A range of methods is used here to estimate the probability of the next earthquake occurring on the central section of the Alpine Fault and all the calculated probabilities are relatively high. The most robust method, that of Nishenko and Buland 1987, suggests a conditional fifty-year probability in the order of 65 ± 15%. A sensitivity analysis indicates that the conditional probabilities of rupture are not significantly affected by assumptions regards the exact timing of the last earthquake, or even the number of most recent earthquakes, and conditional fifty-year probabilities of rupture remain at around 50% or higher. Based on the previous earthquake events, the next Alpine Fault earthquake is likely to have a Moment Magnitude of 8 ± 0.25, and will have a widely felt regional impact. Very strong ground shaking will occur in the epicentral area of the Southern Alps and central Westland. For most of the central South Island the ground shaking is likely to be stronger than that experienced in any other historical earthquake. Landslides and liquefaction will cause the greatest immediate damage to the natural environment, and in the longer-term increased sediment loads will cause aggradation, channel avulsion, and flooding in the numerous rivers which drain the epicentral region. There will also be substantial and widespread damage to the built environment, in some cases at a considerable distance from the epicentre. Because of the rugged nature of the topography of the central South Island, and the expected regional extent of the earthquake shaking, one of the greatest problems during the post earthquake recovery phase will be difficulty in communication and access.

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Claridge, Jonathan William Roy. "Patterns of Crustal Deformation Resulting from the 2010 Earthquake Sequence in Christchurch, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2012. http://hdl.handle.net/10092/7910.

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The Mw 7.1 Darfield earthquake generated a ~30 km long surface rupture on the Greendale Fault and significant surface deformation related to related blind faults on a previously unrecognized fault system beneath the Canterbury Plains. This earthquake provided the opportunity for research into the patterns and mechanisms of co-seismic and post-seismic crustal deformation. In this thesis I use multiple across-fault EDM surveys, logic trees, surface investigations and deformation feature mapping, seismic reflection surveying, and survey mark (cadastral) re-occupation using GPS to quantify surface displacements at a variety of temporal and spatial scales. My field mapping investigations identified shaking and crustal displacement-induced surface deformation features south and southwest of Christchurch and in the vicinity of the projected surface traces of the Hororata Blind and Charing Cross Faults. The data are consistent with the high peak ground accelerations and broad surface warping due to underlying reverse faulting on the Hororata Blind Fault and Charing Cross Fault. I measured varying amounts of post-seismic displacement at four of five locations that crossed the Greendale Fault. None of the data showed evidence for localized dextral creep on the Greendale Fault surface trace, consistent with other studies showing only minimal regional post-seismic deformation. Instead, the post-seismic deformation field suggests an apparent westward translation of northern parts of the across-fault surveys relative to the southern parts of the surveys that I attribute to post-mainshock creep on blind thrusts and/or other unidentified structures. The seismic surveys identified a deformation zone in the gravels that we attribute to the Hororata Blind Fault but the Charing Cross fault was not able to be identified on the survey. Cadastral re-surveys indicate a deformation field consistent with previously published geodetic data. We use this deformation with regional strain rates to estimate earthquake recurrence intervals of ~7000 to > 14,000 yrs on the Hororata Blind and Charing Cross Faults.

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Stahl, Timothy. "Active Tectonics and Geomorphology of the central South Island, New Zealand: Earthquake Hazards of Reverse Faults." Thesis, University of Canterbury. Department of Geological Sciences, 2014. http://hdl.handle.net/10092/9889.

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Oblique continental collision between the Pacific and Australian Plates in the central South Island of New Zealand (between c. 44 and 46°S) results in distributed reverse faulting. Only a few of these faults have been studied in detail, highlighting a major knowledge deficit in the earthquake behaviour, magnitude potential and contribution to seismic hazard for many faults in this part of the orogen. Three reverse faults are investigated in detail in this thesis: the Moonlight Fault Zone (MFZ), the Fox Peak Fault and the Forest Creek Fault. Geochronologic approaches, including Schmidt hammer exposure-age dating, radiocarbon dating, and optically stimulated luminescence dating, are combined with paleoseismic trenching, fault surface trace mapping, analysis of GPS and LiDAR survey data, and numerical modelling to characterise the rupture behaviour of these faults. A new Schmidt hammer chronofunction based on over 7000 clast analyses is developed that relates rebound value (R-value) to age for river terraces. The rapid, inexpensive, non-destructive, and statistically valid nature of this technique makes it widely applicable for age dating here and globally. I use Schmidt hammer exposure-age dating along with other geochronologic and surveying methods to show that stranded post-last glacial lake shorelines of Lake Wakatipu are undeformed and at a uniform elevation across the MFZ. This indicates an absence of uplift across the MFZ since c. 13 ka and suggests that this fault may be inactive or subject to long periods of interseismic quiescence despite its location in the active orogen. This result also challenges the long-held hypothesis that lake shorelines throughout central NZ are tilted due to isostatic rebound. Three segments of the Fox Peak Fault are identified through field mapping and surveying. Slip rates at over 50 locations along the 36.5 km total length of the fault (c. 1.5 mm yr⁻¹ maximum) co-vary with the bounding range topography and exhibit large gradients near intersecting NW-striking faults. Four paleoseismic trenches were excavated to determine if these segment boundaries represent barriers to earthquake rupture propagation. Evidence of 3-4 earthquakes since c. 16 ka on the two end segments with overlapping age uncertainties indicates that the recurrence interval of the fault is 2000-3000 years. The most recent event (MRE) occurred at c. 2.5 ka. Large single event displacement to length ratios on these segments and a single event scarp on the central segment indicate that while the segment boundaries control on-fault slip gradients, they are not likely to impede through-going ruptures in an earthquake. This is a relatively recent development from the long-term tectonic geomorphology, which is suggestive of range growth on separate faults.

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Kim, Ji Hyun. "Quantitative analysis of factors influencing post-earthquake decisions on concrete buildings in Christchurch, New Zealand." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/53913.

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The 2010-2011 Canterbury Earthquake Sequence resulted in unprecedented losses including 185 casualties, an estimated $NZ 40 billion cost of rebuild, and the demolition of 60% of reinforced concrete buildings in the Christchurch Central Business District (CBD). Intriguingly, demolition rate is unexpectedly high compared to the reported damages. This study thus sought to explore factors influencing the post-earthquake decisions on buildings (demolition or repair). Focusing the study on multi-storey reinforced concrete buildings in the Christchurch CBD, information on building characteristics, assessed post-earthquake damage, and post-earthquake decision (demolish or repair) for 223 buildings was collected. Data were obtained on approximately 88% of the 3-storey and higher reinforced concrete buildings within the CBD, or approximately 34% of all reinforced concrete buildings in the CBD. The study of descriptive statistics and trends of the database confirms that a significant portion of repairable buildings were demolished. Logistic regression models were developed based on the collected empirical data. From the significance testing, the assessed damage, occupancy type, heritage status, number of floors, and construction year were identified as variables influencing the building-demolition decision. Their effects on the post-earthquake decisions were approximated, and the resulting likelihood of building demolition was estimated for buildings with different attributes. From personal interviews with 9 building owners, 9 building developers and investors, 5 insurance sector representatives, and 4 local engineers and government authority personnel, it was learned that the local context, such as insurance policy and changes in local legislation, also played a significant role in the decision-making process. As the first quantitative study that explores the effects of factors on the post-earthquake building demolition decisions, the findings of this study indicates that the damage is not the only factor affecting the post-earthquake decisions on buildings. Incorporation of all influential factors in the probability-of-demolition function would provide better means of estimating expected total loss by considering decision outcome scenarios and associated costs. This would benefit the decision makers with comprehensive and valuable information concerning seismic risk management and strategy. Limitations on this study are discussed and similar studies are suggested reflecting the locality of different communities with seismic risk.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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Brehaut, Janet Catherine. "2D-Modelling of Earthquake-Induced Rockfall from Basaltic Ignimbrite Cliffs at Redcliffs, Christchurch, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2012. http://hdl.handle.net/10092/9172.

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This thesis is concerned with modelling rockfall parameters associated with cliff collapse debris and the resultant “ramp” that formed following the high peak ground acceleration (PGA) events of 22 February 2011 and 13 June 2011. The Christchurch suburb of Redcliffs, located at the base of the Port Hills on the northern side of Banks Peninsula, New Zealand, is comprised of Miocene-age volcanics with valley-floor infilling marine sediments. The area is dominated by basaltic lava flows of the Mt Pleasant Formation, which is a suite of rocks forming part of the Lyttelton Volcanic Group that were erupted 11.0-10.0Ma. Fresh exposure enabled the identification of a basaltic ignimbrite unit at the study site overlying an orange tuff unit that forms a marker horizon spanning the length of the field area. Prior to this thesis, basaltic ignimbrite on Banks Peninsula has not been recorded, so descriptions and interpretations of this unit are the first presented. Mapping of the cliff face by remote observation, and analysis of hand samples collected from the base of the debris slopes, has identified a very strong (>200MPa), columnar-jointed, welded unit, and a very weak (<5MPa), massive, so-called brecciated unit that together represent the end-member components of the basaltic ignimbrite. Geochemical analysis shows the welded unit is picrite basalt, and the brecciated unit is hawaiite, making both clearly distinguishable from the underlying trachyandesite tuff. RocFall™ 4.0 was used to model future rockfalls at Redcliffs. RocFall™ is a two-dimensional (2D), hybrid, probabilistic modelling programme for which topographical profile data is used to generate slope profiles. GNS Science collected the data used for slope profile input in March 2011. An initial sensitivity analysis proved the Terrestrial Laser Scan (TLS)-derived slope to be too detailed to show any results when the slope roughness parameter was tested. A simplified slope profile enabled slope roughness to be varied, however the resulting model did not correlate with field observations as well. By using slope profile data from March 2011, modelled rockfall behaviour has been calibrated with observed rockfall runout at Redcliffs in the 13 June 2011 event to create a more accurate rockfall model. The rockfall model was developed on a single slope profile (Section E), with the chosen model then applied to four other section lines (A-D) to test the accuracy of the model, and to assess future rockfall runout across a wider area. Results from Section Lines A, B, and E correlate very well with field observations, with <=5% runout exceeding the modelled slope, and maximum bounce height at the toe of the slope <=1m. This is considered to lie within observed limits given the expectation that talus slopes will act as a ramp on which modelled rocks travel further downslope. Section Lines C and D produced higher runout percentage values than the other three section lines (23% and 85% exceeding the base of the slope, respectively). Section D also has a much higher maximum bounce height at the toe of the slope (~8.0m above the slope compared to <=1.0m for the other four sections). Results from modelling of all sections shows the significance of the ratio between total cliff height (H) and horizontal slope distance (x), and of maximum drop height to the top of the talus (H*) and horizontal slope distance (x). H/x can be applied to the horizontal to vertical ratio (H:V) as used commonly to identify potential slope instability. Using the maximum value from modelling at Redcliffs, the future runout limit can be identified by applying a 1.4H:1V ratio to the remainder of the cliff face. Additionally, the H*/x parameter shows that when H*/x >=0.6, the percentage of rock runout passing the toe of the slope will exceed 5%. When H*/x >=0.75, the maximum bounce height at the toe of the slope can be far greater than when H*/x is below this threshold. Both of these parameters can be easily obtained, and can contribute valuable guideline data to inform future land-use planning decisions. This thesis project has demonstrated the applicability of a 2D probabilistic-based model (RocFall™ 4.0) to evaluate rockfall runout on the talus slope (or ramp) at the base of ~35-70m high cliff with a basaltic ignimbrite source. Limitations of the modelling programme have been identified, in particular difficulties with adjusting modelled roughness of the slope profile and the inability to consider fragmentation. The runout profile using RocFall™ has been successfully calibrated against actual profiles and some anomalous results have been identified.

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Sheridan, Mattilda. "The effects of an Alpine Fault earthquake on the Taramakau River, South Island New Zealand." Thesis, University of Canterbury. Geology, 2014. http://hdl.handle.net/10092/10253.

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An Alpine Fault Earthquake has the potential to cause significant disruption across the Southern Alps of the South Island New Zealand. In particular, South Island river systems may be chronically disturbed by the addition of large volumes of sediment sourced from coseismic landsliding. The Taramakau River is no exception to this; located north of Otira, in the South Island of New Zealand, it is exposed to natural hazards resulting from an earthquake on the Alpine Fault, the trace of which crosses the river within the study reach. The effects of an Alpine Fault Earthquake (AFE) have been extensively studied, however, little attention has been paid to the effects of such an event on the Taramakau River as addressed herein. Three research methods were utilised to better understand the implications of an Alpine Fault Earthquake on the Taramakau River: (1) hydraulic and landslide data analyses, (2) aerial photograph interpretation and (3) micro-scale modelling. Data provided by the National Institute of Water and Atmospheric Research were reworked, establishing relationships between hydraulic parameters for the Taramakau River. Estimates of landslide volume were compared with data from the Poerua landslide dam, a historic New Zealand natural event, to indicate how landslide sediment may be reworked through the Taramakau valley. Aerial photographs were compared with current satellite images of the area, highlighting trends of avulsion and areas at risk of flooding. Micro-scale model experiments indicated how a braided fluvial system may respond to dextral strike-slip and thrust displacement and an increase in sediment load from coseismic landslides. An Alpine Fault Earthquake will generate a maximum credible volume of approximately 3.0 x 108 m3 of landslide material in the Taramakau catchment. Approximately 15% of this volume will be deposited on the Taramakau study area floodplain within nine years of the next Alpine Fault Earthquake. This amounts to 4.4 x 107 m3 of sediment input, causing an average of 0.5 m of aggradation across the river floodplains within the study area. An average aggradation of 0.5 m will likely increase the stream height of a one-in-100 year flood with a flow rate of 3200 m3/s from seven metres to 7.5 m overtopping the road and rail bridges that cross the Taramakau River within the study area – if they have survived the earthquake. Since 1943 the Taramakau River has shifted 500 m away from State Highway 73 near Inchbonnie, moving 430 m closer to the road and rail. Paleo channels recognised across the land surrounding Inchbonnie between the Taramakau River and Lake Brunner may be reoccupied after an earthquake on the Alpine Fault. Micro-scale modelling showed that the dominant response to dextral strike-slip and increased ‘landslide’ sediment addition was up- and downstream aggradation separated by a localised zone of degradation over the fault trace. Following an Alpine Fault Earthquake the Taramakau River will be disturbed by the initial surface rupture along the fault trace, closely followed by coseismic landsliding. Landslide material will migrate down the Taramakau valley and onto the floodplain. Aggradation will raise the elevation of the river bed promoting channel avulsion with consequent flooding and sediment deposition particularly on low lying farmland near Inchbonnie. To manage the damage of these hazards, systematically raising the low lying sections of road and rail may be implemented, strengthening (or pre-planning the replacement of) the bridges is recommended and actively involving the community in critical decision making should minimise the risks of AFE induced fluvial hazards. The response of the Taramakau River relative to an Alpine Fault Earthquake might be worse, or less severe or significantly different in some way, to that assumed herein.

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Yanicki, Sarah Rachel. "A Tale of Two Suburbs: Earthquake recovery and civil society in Christchurch." Thesis, University of Canterbury. School of Social and Political Sciences, 2013. http://hdl.handle.net/10092/8730.

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This study followed two similarly affected, but socio-economically disparate suburbs as residents responded to and attempted to recover from the devastating 6.3 magnitude earthquake that struck Christchurch, New Zealand, on February 22, 2011. More specifically, it focuses on the role of local churches, community-based organisations (CBOs) and non-governmental organisations (NGOs), here referred to broadly as civil society, in meeting the immediate needs of local residents and assisting with the longer-term recovery of each neighbourhood. Despite considerable socioeconomic differences between the two neighbourhoods, civil society in both suburbs has been vital in addressing the needs of locals in the short and long term following the earthquake. Institutions were able to utilise local knowledge of both residents and the extent of damage in the area to a) provide a swifter local response than government or civil defence and then help direct the relief these agencies provided locally; b) set up central points for distribution of supplies and information where locals would naturally gather; c) take action on what were perceived to be unmet needs; and d) act as a way of bridging locals to a variety of material, informational, and emotional resources. However the findings also support literature which indicates that other factors are also important in understanding neighbourhood recovery and the role of civil society, including: local leadership; a shared, place-based identity; the type and form of civil society organizations; social capital; and neighbourhood- and household-level indicators of relative vulnerability and inequality. The intertwining of these various factors seems to influence how these neighbourhoods have coped with and taken steps in recovering from this disaster. It is recommended that future research be directed at developing a better understanding of how this occurs. It is suggested that a model similar to Yasui’s (2007) Community Vulnerability and Capacity model be developed as a useful way to approach future research in this area.

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Marquis, Frederic. "A framework for understanding post-earthquake decisions on multi-storey concrete buildings in Christchurch, New Zealand." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54058.

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The 2010-2011 Canterbury earthquakes, which involved widespread damage during the February 2011 event and subsequent aftershocks, left this community with more than $NZD 40 billion in losses, demolition of approximately 60% of multi-storey concrete buildings, and closure of the core business district for over 2 years. This thesis presents a framework to understand the issues and complexities in relation to post-earthquake decisions (repair or demolish) on multi-storey concrete buildings in Christchurch. The primary research data for this thesis were collected through in-depth investigations on 15 case-study buildings using 27 interviews with various building stakeholders in New Zealand. As expected, the level of damage and repairability (cost to repair) generally dictated the course of action. There is strong evidence, however, that variables such as insurance, business strategies, perception of risks, uncertainty, and building regulations have significantly influenced the decision on a number of buildings. The decision-making process for each building is typically complex and unique, not solely driven by structural damage. The analysis of the case-study buildings and the interviews have shown that the main driving factors in the predominance of building demolitions in Christchurch were the ambiguous wording of insurance policies offered in New Zealand, the changes in building regulations following the earthquakes, and the lack of criteria for the evaluation of the residual capacity of damaged structures. Because of inadequate insurance cover, conservative engineering evaluations due to uncertainties in structural damage and capacity, and the difficulty of satisfying policy clauses, buildings were often considered uneconomical to repair. Furthermore, most property investors interviewed considered it a favourable outcome if their building was declared a total loss by their insurer and subsequently demolished, because of the availability, flexibility, and rapidity of cash settlements. This thesis also argues that the absence of clear criteria for the repairability of earthquake-damaged buildings implicitly counteracts resilience and sustainable development objectives of building codes. This lack of standards contributed to the demolition of potentially salvageable buildings, resulting in a substantial loss of the built environment.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

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14

Hollis, Melanie. "Formulating Disaster Recovery Plans for New Zealand: using a case study of the 1931 Napier Earthquake." Thesis, University of Canterbury. Geological Sciences, 2007. http://hdl.handle.net/10092/1456.

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Worldwide, the risks from natural and technological hazards has been mounting at an accelerating rate, improvements in forecasting and warning systems have reduced deaths, however monetary losses from disasters are overwhelming (Burby, 2004). Pre event planning for recovery helps to resolve issues before a disaster so recovery is more efficient and effective. It also ensures that the window of opportunity can be used to implement hazard mitigation measures to reduce the vulnerability of the area with the aim of improving resilience for the next disaster. International case studies were examined, the Northridge earthquake being the most successful recovery while Hurricane Katrina the least. The recovery of the Napier 1931 earthquake was chosen as a New Zealand case study; to date this is the country's worst disaster. Overall the recovery of Napier was a success, shops were opened in temporary premises to keep the economy going and mitigation measures were included in the rebuilding. The earthquake has had important flow on effects on the way that disasters are managed in New Zealand. To create pre event plans in New Zealand legislation needs to be modified, including recovery plans and development of shortcuts to reduce some procedures which lengthen the recovery process. These plans need to take into account our national vulnerability as well as regional vulnerabilities.

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Maurer, Brett. "Moving Towards an Improved Liquefaction Hazard Framework: Lessons Resulting From the 2010-2011 Canterbury, New Zealand, Earthquake Sequence." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73322.

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The 2010-2011 Canterbury, New Zealand, Earthquake Sequence (CES) resulted in a liquefaction dataset of unprecedented size and quality, presenting a truly unique opportunity to assess and improve the efficacy of liquefaction-analytics in the field. Towards this end, the study presented herein develops and analyzes a database of 10,000 high-quality liquefaction case histories resulting from the CES. The objectives of these analyses are varied, but underlying each is the desire to more accurately assess liquefaction hazard for civil infrastructure (i.e., to predict both the occurrence and damage-potential of soil liquefaction). Major contributions from this work include, but are not limited to: (1) the Liquefaction Potential Index (LPI), the state-of-practice framework for assessing liquefaction hazard, is shown to produce erroneous predictions for a significant percentage of the assessed case histories; (2) the cause of poor predictions is rigorously investigated and specific shortcomings of the LPI framework are identified; (3) based on the limitations identified, and using insights from historical data, a revised liquefaction hazard framework is developed; and (4) the revised framework is shown to assess liquefaction hazard more efficiently relative to both LPI and a competing alternative framework newly proposed in the literature. Ultimately, significant room for improvement remains with respect to accurate assessment of liquefaction hazard. The findings presented in this dissertation thus form the basis for future development of a further-improved framework. Moreover, a methodology is proposed by which improvements can be measured in a standardized and objective manner.
Ph. D.

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De, Pascale Gregory Paul. "Neotectonics and Paleoseismology of the Central Alpine Fault, New Zealand." Thesis, University of Canterbury. Geological Sciences, 2014. http://hdl.handle.net/10092/8908.

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The Alpine Fault is a major plate boundary structure, which accommodates up to 50-80% of the total plate boundary motion across the South Island of New Zealand. The fault has not ruptured historically although limited off-fault shaking records and on-fault dating suggest large to great (~ Mw 8) earthquakes (every ~100-480 years; most recently in 1717), making it potentially one of the largest onshore sources of seismic hazard in New Zealand. The central section of the Alpine Fault, which bounds the highest elevations in the Southern Alps, is one of the most poorly characterised sections along the fault. On-fault earthquake timing in addition to the amount of dextral slip during major earthquakes was unknown along a 200-km-long section of the central Alpine Fault, while the amount of co-seismic hanging wall uplift was poorly known, prior to the present work. In this thesis I address these knowledge gaps through a combination of light detection and ranging (lidar), field, and stratigraphic mapping along with sample dating to constrain earthquake timing, style of faulting, and hanging wall rock uplift rates. Using lidar data coupled with field mapping I delineated the main trace of the Alpine Fault at Gaunt Creek as a north-striking fault scarp that was excavated and logged; this is part of a 2-km-wide restraining bend dominated by low-angle thrust faulting and without the clear strike-slip displacements that are present nearby (<5 km distant along strike in both directions). Where exposed in this scarp, the fault-zone is characterized by a distinct 5-50 cm thick clay fault-gouge layer juxtaposing hanging wall bedrock (mylonites and cataclasites) over unconsolidated late-Holocene footwall colluvium. An unfaulted peat at the base of the scarp is buried by post-most recent event (MRE) alluvium and yields a radiocarbon age of A.D. 1710–1930, consistent with sparse on-fault data, validating earlier off-fault records that suggest a 1717 MRE with a moment magnitude of Mw 8.1 ± 0.1, based on the 380-km-long surface rupture. Lidar and field mapping also enabled the identification and measurement of short (<30 m), previously unrecognized dextral offsets along the central section of the Alpine Fault. Single-event displacements of 7.5 ± 1 m for the 1717 earthquake and cumulative displacements of 12.9 ± 2 m and 22 ± 2.7 m for earlier ruptures can be binned into 7.1 ± 2.1 m increments of repeated dextral (uniform) slip along the central Alpine Fault. A comparison of these offsets with the local paleoseismic record and known plate kinematics suggests that the central Alpine Fault earthquakes in the past 1.1 ka may have: (i) bimodal character, with major surface ruptures (!Mw 7.9) every 270 ± 70 years (e.g. the 1717 event) and with moderate to large earthquakes (!Mw 7) occurring between these ruptures (e.g. the 1600 event); or (ii) that some shaking data may record earthquakes on other faults. If (i) is true, the uniform slip model (USM) perhaps best represents central Alpine Fault earthquake recurrence, and argues against the applicability of the characteristic earthquake model (CEM) there. Alternatively, if (ii) is true, perhaps the fault is “characteristic” and some shaking records proximal to plate boundary faults do not necessarily reflect plate-boundary surface ruptures. Paleoseismic and slip data suggest that (i) is the most plausible interpretation, which has implications for the understanding of major plate-boundary faults worldwide. Field mapping, geological characterisation, geophysical mapping, and optically stimulated luminescence (OSL) dating of on-fault hanging wall sediments were used to better constrain the geometry and kinematics of Holocene deformation along the rangefront of the Southern Alps at the Alpine Fault near the Whataroa River. The fault here is dextral-reverse, although primarily strike-slip with clear fault traces cutting across older surfaces of varying elevations. Deformational bulges are observed along these traces that are likely thrust-bounded. A terrace of Whataroa River sediments was found on the hanging wall of the Alpine Fault approximately ~ 55-75 m (when considering uncertainties) above the floodplain of the Whataroa River. OSL ages for a hanging wall sediments of 10.9 ± 1.0 ka for the aforementioned terrace, 2.8 ± 0.3 ka for Whataroa River terrace deposits in a deformational bulge, and 11.1 ± 1.2 ka for a rangefront derived fan indicate Holocene aggradation along the rangefront and hanging wall uplift rates of 6.0 ± 1.1 mm/yr. The sub-horizontal, laterally continuous, and planar-bedded Whataroa-sourced terrace deposits suggest that the adjacent bounding faults are steeply-dipping faults without geometries in the shallow subsurface that would tend to cause sedimentary bed rotation and tilting. Using data from the approximately 100-m deep pilot DFDP boreholes together with lidar and field mapping, I present a review of the Quaternary geology, geomorphology, and structure of the fault at Gaunt Creek, and estimate new minimum Late-Pleistocene hanging wall rock uplift rates of 5.7 ± 1.0 mm/yr to 6.3 ± 1.1 mm/yr (without considering local erosion) that suggest that the Southern Alps are in a dynamic steady state here. GPS-derived “interseismic” vertical uplift rates are < 1 mm/yr at the Alpine Fault, so the majority of rock uplift at the rangefront happens during episodic major earthquakes, confirming with on-fault data that slip occurs coseismically. Notably the uplift rates from both Mint and Gaunt Creek are consistent between the two sites although the primary style of faulting at the surface is different between the two sites, suggesting consistent coseisimc uplift of the Southern Alps rangefront along the Alpine Fault in major earthquakes. This thesis collected new on-fault datasets that confirm earlier inferences of plate-boundary fault behaviour. This study of the high-uplift central section of the Alpine Fault provides the first on-fault evidence for the MRE (i.e. 1717) and repeated of dextral slip during the MRE and previous events as well as new hanging wall uplift data which suggests that the majority of rangefront uplift occurs in earthquakes along the Alpine Fault. Because the fault has not ruptured for ~300 years, it poses a significant seismic hazard to southern New Zealand.

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Holtkamp, Stephen Gregg. "NEW METHODS FOR DETECTING EARTHQUAKE SWARMS AND TRANSIENT MOTION TO CHARACTERIZE HOW FAULTS SLIP." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1369741772.

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18

Dianiska, Kathryn Elise. "The interplay between deformation and metamorphism during strain localization in the lower crust: Insights from Fiordland, New Zealand." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/387.

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In this thesis, I present field, microstructural, and Electron Backscatter Diffraction (EBSD) analyses of rock fabrics from high strain zones in exposures of lower crustal Cretaceous plutons at Breaksea Entrance, Fiordland, New Zealand. The interplay between deformation and metamorphism occurs across multiple scales at the root of a continental arc. I show a series of steps in which retrogressive metamorphism is linked to the accommodation of deformation. I define three main phases of deformation and metamorphism at Breaksea Entrance. The first phase (D1) involved emplacement of dioritic to gabbroic plutons at depths up to 60 km. The second phase (D2) is characterized by deformation and metamorphism at the granulite and eclogite facies that produced high strain zones with linear fabrics, isoclinal folding of igneous layering, and asymmetric pressure shadows around mafic aggregates. New structural analyses from Hāwea Island in Breaksea Entrance reveal the development of doubly plunging folds that define subdomes within larger, kilometer-scale gneiss domes. The development and intensification of S2 foliations within the domes was facilitated by the recrystallization of plagioclase and clinopyroxene at the micro-scale (subgrain rotation and grain boundary migration recrystallization), consistent with metamorphism at the granulite and eclogite facies and climb-accommodated dislocation creep. EBSD data show a strong crystallographic preferred orientation in plagioclase during D2 deformation. The third phase (D3) is characterized by deformation and metamorphism at the upper amphibolite facies that produced sets of discrete, narrow shear zones that wrap and encase lozenges of older fabrics. Structural analyses reveal a truncation and/or transposition relationship between the older S2 and the younger S3 foliations developed during D3. Progressive localization of deformation during cooling, hydration, and retrogression, resulted in the breakdown of garnet and pyroxene to form hornblende, biotite, fine plagioclase and quartz. EBSD data show a strong crystallographic preferred orientation in hornblende. During D3, hornblende and biotite accommodated most of the strain through fluid-assisted diffusion creep. The last two events (D2 and D3) reflect a transition in deformation and metamorphism during exhumation, as well as a focusing of strain and evolving strain localization mechanisms at the root of a continental arc. An examination of structures at multiple scales of observation reveals that fabrics seen in the field are a composite of multiple generations of deformation and metamorphism.

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Schuck, Bernhard [Verfasser], Georg [Akademischer Betreuer] Dresen, and Virginia [Akademischer Betreuer] Toy. "Geomechanical and petrological characterisation of exposed slip zones, Alpine Fault, New Zealand / Bernhard Schuck ; Georg Dresen, Virginia Toy." Potsdam : Universität Potsdam, 2020. http://d-nb.info/1218496223/34.

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20

Hutt, Shevelle Dionne. "First Responders to Cataclysmic Upheaval: Earthquake–Driven Effects on Microalgae in the Avon-Heathcote Estuary, Christchurch, New Zealand." Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/10345.

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The Avon-Heathcote Estuary is of significant value to Christchurch due to its high productivity, biotic diversity, proximity to the city, and its cultural, recreational and aesthetic qualities. Nonetheless, it has been subjected to decades of degradation from sewage wastewater discharges and encroaching urban development. The result was a eutrophied estuary, high in nitrogen, affected by large blooms of nuisance macroalgae and covered by degraded sediments. In March 2010, treated wastewater was diverted from the estuary to a site 3 km offshore. This quickly reduced water nitrogen by 90% within the estuary and, within months, there was reduced production of macroalgae. However, a series of earthquakes beginning in September 2010 brought massive changes: tilting of the estuary, changes in channels and water flow, and a huge influx of liquefied sediments that covered up to 65% of the estuary floor. Water nitrogen increased due to damage to sewage infrastructure and the diversion pipeline being turned off. Together, these drastically altered the estuarine ecosystem. My study involves three laboratory and five in situ experiments that investigate the base of the food chain and responses of benthic microalgae to earthquake-driven sediment and nutrient changes. It was predicted that the new sediments would be coarser and less contaminated with organic matter and nutrients than the old sediments, would have decreased microalgal biomass, and would prevent invertebrate grazing and bioturbation activities. It was believed that microalgal biomass would become similar across new and old sediments types as the unstable new sediments were resuspended and distributed over the old sediments. Contact cores of the sediment were taken at three sites, across a eutrophication gradient, monthly from September 2011 to March 2012. Extracted chlorophyll a pigments showed that microalgal biomass was generally lower on new liquefied sediments compared to old sediments, although there was considerable site to site variation, with the highly eutrophic sites being the most affected by the emergence of the new sediments. Grazer experiments showed that invertebrates had both positive and negative site-specific effects on microalgal biomass depending on their identity. At one site, new sediments facilitated grazing by Amphibola crenata, whereas at another site, new sediments did not alter the direct and indirect effects of invertebrates (Nicon aestuariensis, Macropthalmus hirtipes, and A. crenata) on microalgae. From nutrient addition experiments it was clear that benthic microalgae were able to use nutrients from within both old and new sediments equally. This implied that microalgae were reducing legacy nutrients in both sediments, and that they are an important buffer against eutrophication. Therefore, in tandem with the wastewater diversion, they could underpin much of the recovery of the estuary. Overall, the new sediments were less favourable for benthic microalgal growth and recolonisation, but were less contaminated than old sediments at highly eutrophic sites. Because the new sediments were less contaminated than the old sediments, they could help return the estuary to a noneutrophic state. However, if the new sediments, which are less favourable for microalgal growth, disperse over the old sediments at highly eutrophic sites, they could become contaminated and interfere with estuarine recovery. Therefore, recovery of microalgal communities and the estuary was expected to be generally long, but variable and site-specific, with the least eutrophic sites recovering quickly, and the most eutrophic sites taking years to return to a pre-earthquake and non-eutrophied state. changes in channels and water flow, and a huge influx of liquefied sediments that covered up to 65% of the estuary floor. Water nitrogen increased due to damage to sewage infrastructure and the diversion pipeline being turned off. Together, these drastically altered the estuarine ecosystem. My study involves three laboratory and five in situ experiments that investigate the base of the food chain and responses of benthic microalgae to earthquake-driven sedimen tand nutrient changes. It was predicted that the new sediments would be coarser and less contaminated with organic matter and nutrients than the old sediments, would have decreased microalgal biomass, and would prevent invertebrate grazing and bioturbation activities. It was believed that microalgal biomass would become similar across new and old sediments types as the unstable new sediments were resuspended and distributed over the old sediments. Contact cores of the sediment were taken at three sites, across a eutrophication gradient, monthly from September 2011 to March 2012. Extracted chlorophyll a pigments showed that microalgal biomass was generally lower on new liquefied sediments compared to old sediments, although there was considerable site to site variation, with the highly eutrophic sites being the most affected by the emergence of the new sediments. Grazer experiments showed that invertebrates had both positive and negative site-specific effects on microalgal biomass depending on their identity. At one site, new sediments facilitated grazing by Amphibola crenata, whereas at another site, new sediments did not alter the direct and indirect effects of invertebrates (Nicon aestuariensis, Macropthalmus hirtipes, and A. crenata) on microalgae. From nutrient addition experiments it was clear that benthic microalgae were able to use nutrients from within both old and new sediments equally. This implied that microalgae were reducing legacy nutrients in both sediments, and that they are

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21

Hutton, Nicole Suzanne. "Population Dynamics and Vulnerability Reduction: The Role of Non-Profit Organizations Following the 2011 Earthquake in Christchurch, New Zealand." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/5964.

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With the adoption of neo-liberal policies and the decline in social welfare, non-profit organizations have been increasingly integrated into public service provision. Such changes raise questions regarding formal policies and access for marginalized populations, no more so than in disaster settings as formal disaster management of sexual health services are still vague. This study identifies the role of non-profit organizations in providing public health and social services through the lens of sexual health commitments following the September 2010 Darfield Earthquake and subsequent major aftershock during February 2011 in Christchurch, New Zealand. The primary goals of this study were three fold, to delineate i) aspects of non-profit organizational culture and agency connections that contributed to the resilience of non-profit organizations by maintaining and adapting access to sexual health and associated wellbeing services over the transition from response to recovery ii) integration pathways of non-profit organizations into disaster risk reduction and iii) appropriate geographic representations of temporal vulnerability change impacting the commitments of non-profit organizations. Mixed methods were used for this study. Data were collected over a two-year period between 2013 and 2015. Data collection techniques included: i) archival research ii) surveys iii) focus groups and iv) semi-structured interviews. Quantitative data were derived from census records and qualitative data from surveys, focus groups, and interviews with non-profit and civil society practitioners. A total of thirty-six non-profit organizations, civil society partners, and agency connections participated. Results show that sexual health needs of youth, families, and migrants arriving for the rebuild, fluctuated following the earthquakes. Sexual health non-profits absorbed the shifting demands for services and supplies by leveraging government partnerships and non-profit agency connections to account for fluctuations in presenting populations, adjust service delivery methods and continue advocacy campaigns. Also, as a result of functional redundancy amongst migrant support groups and their respective agency connections, strategies of long-term advocacy commitment, co-location, and relationship building with diverse ethnic groups benefitted migrants and refugees in maintaining or accessing adequate health and wellbeing support into the recovery phase. By developing programs to increase public awareness of resources, creating engagement opportunities in vacant spaces, and bringing a united voice to authorities, non-profits captured increased social cohesion to address emergent and compounded vulnerabilities of marginalized populations. However, as the recovery progressed, some collective energy was lost. Findings indicate that non-profits operating in Christchurch prior to the earthquakes with flexible organizational structures and those that emerged after were most successful in the emergency response and early recovery. The ability to capture social cohesion resulting from the shared experience of the earthquakes and build bridges with non-profit connections or incorporate emergent populations into service delivery facilitated successful operations into recovery. Non-profits that partnered with the government were better suited for long-term recovery, when interagency collaboration returned to a more competitive state and reliance on co-production of services was reestablished as the preferred method of service delivery, based on their capacity to maintain and build linkages with civil society partners. This research adds to disaster literature and the understanding of organizational behaviors by suggesting appropriate means to assess the potential resilience of non-profit organizations post-disaster. Further, pathways of integration with disaster management are identified for various types of non-profits that contribute to sexual health and related community support services. Methods used to identify vulnerabilities of wellbeing focused non-profit organizations and model integration of culturally appropriate service delivery options into recovery planning and disaster mitigation can be applied to other high-income nations with burgeoning non-profit sectors that experience variety of hazards, in particular on the United States’ West Coast as the health care debate in the United States continues.

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Kelland, Emma Jean. "Vulnerabilities to Seismic Hazards in Coastal and River Environments: Lessons post the Canterbury Earthquake Sequence 2010-2012, New Zealand." Thesis, University of Canterbury. Geography, 2013. http://hdl.handle.net/10092/8487.

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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.

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Skilton, Jennifer Erin. "Invertebrate Responses to Large-Scale Change : Impacts of Eutrophication and Cataclysmic Earthquake Events in a Southern New Zealand Estuary." Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/8725.

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Environmental stress and disturbance can affect the structure and functioning of marine ecosystems by altering their physical, chemical and biological features. In estuaries, benthic invertebrate communities play important roles in structuring sediments, influencing primary production and biogeochemical flux, and occupying key food web positions. Stress and disturbance can reduce species diversity, richness and abundance, with ecological theory predicting that biodiversity will be at its lowest soon after a disturbance with assemblages dominated by opportunistic species. The Avon-Heathcote Estuary in Christchurch New Zealand has provided a novel opportunity to examine the effects of stress, in the form of eutrophication, and disturbance, in the form of cataclysmic earthquake events, on the structure and functioning of an estuarine ecosystem. For more than 50 years, large quantities (up to 500,000m3/day) of treated wastewater were released into this estuary but in March 2010 this was diverted to an ocean outfall, thereby reducing the nutrient loading by around 90% to the estuary. This study was therefore initially focussed on the reversal of eutrophication and consequent effects on food web structure in the estuary as it responded to lower nutrients. In 2011, however, Christchurch was struck with a series of large earthquakes that greatly changed the estuary. Massive amounts of liquefied sediments, covering up to 65% of the estuary floor, were forced up from deep below the estuary, the estuary was tilted by up to a 50cm rise on one side and a corresponding drop on the other, and large quantities of raw sewage from broken wastewater infrastructure entered the estuary for up to nine months. This study was therefore a test of the potentially synergistic effects of nutrient reduction and earthquake disturbance on invertebrate communities, associated habitats and food web dynamics. Because there was considerable site-to-site heterogeneity in the estuary, the sites in this study were selected to represent a eutrophication gradient from relatively “clean” (where the influence of tidal flows was high) to highly impacted (near the historical discharge site). The study was structured around these sites, with components before the wastewater diversion, after the diversion but before the earthquakes, and after the earthquakes. The eutrophication gradient was reflected in the composition and isotopic chemistry of primary producer and invertebrate communities and the characteristics of sediments across the sample sites. Sites closest to the former wastewater discharge pipe were the most eutrophic and had cohesive organic -rich, fine sediments and relatively depauperate communities dominated by the opportunistic taxa Capitellidae. The less-impacted sites had coarser, sandier sediments with fewer pollutants and far less organic matter than at the eutrophic sites, relatively high diversity and lower abundances of micro- and macro-algae. Sewage-derived nitrogen had became incorporated into the estuarine food web at the eutrophic sites, starting at the base of the food chain with benthic microalgae (BMA), which were found to use mostly sediment-derived nitrogen. Stable isotopic analysis showed that δ13C and δ15N values of most food sources and consumers varied spatially, temporally and in relation to the diversion of wastewater, whereas the earthquakes did not appear to affect the overall estuarine food web structure. This was seen particularly at the most eutrophic site, where isotopic signatures became more similar to the cleaner sites over two-and-a-half years after the diversion. New sediments (liquefaction) produced by the earthquakes were found to be coarser, have lower concentrations of heavy metals and less organic matter than old (existing) sediments. They also had fewer macroinvertebrate inhabitants initially after the earthquakes but most areas recovered to pre-earthquake abundance and diversity within two years. Field experiments showed that there were higher amounts of primary production and lower amounts of nutrient efflux from new sediments at the eutrophic sites after the earthquakes. Primary production was highest in new sediments due to the increased photosynthetic efficiency of BMA resulting from the increased permeability of new sediments allowing increased light penetration, enhanced vertical migration of BMA and the enhanced transport of oxygen and nutrients. The reduced efflux of NH4-N in new sediments indicated that the capping of a large portion of eutrophic old sediments with new sediments had reduced the release of legacy nutrients (originating from the historical discharge) from the sediments to the overlying water. Laboratory experiments using an array of species and old and new sediments showed that invertebrates altered levels of primary production and nutrient flux but effects varied among species. The mud snail Amphibola crenata and mud crab Austrohelice crassa were found to reduce primary production and BMA biomass through the consumption of BMA (both species) and its burial from bioturbation and the construction of burrows (Austrohelice). In contrast, the cockle Austrovenus stutchburyi did not significantly affect primary production and BMA biomass. These results show that changes in the structure of invertebrate communities resulting from disturbances can also have consequences for the functioning of the system. The major conclusions of this study were that the wastewater diversion had a major effect on food web dynamics and that the large quantities of clean and unpolluted new sediments introduced to the estuary during the earthquakes altered the recovery trajectory of the estuary, accelerating it at least throughout the duration of this study. This was largely through the ‘capping’ effect of the new liquefied, coarser-grained sediments as they dissipated across the estuary and covered much of the old organic-rich eutrophic sediments. For all aspects of this study, the largest changes occurred at the most eutrophic sites; however, the surrounding habitats were important as they provided the context for recovery of the estuary, particularly because of the very strong influence of sediments, their biogeochemistry, microalgal and macroalgal dynamics. There have been few studies documenting system level responses to eutrophication amelioration and to the best on my knowledge there are no other published studies examining the impacts of large earthquakes on benthic communities in an estuarine ecosystem. This research gives valuable insight and advancements in the scientific understanding of the effects that eutrophication recovery and large-scale disturbances can have on the ecology of a soft-sediment ecosystem.

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Duffy, Brendan Gilbert. "The Structural and Geomorphic Development of Active Collisional Orogens, from Single Earthquake to Million Year Timescales, Timor Leste and New Zealand." Thesis, University of Canterbury. Department of Geological Sciences, 2012. http://hdl.handle.net/10092/7527.

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The structure and geomorphology of active orogens evolves on time scales ranging from a single earthquake to millions of years of tectonic deformation. Analysis of crustal deformation using new and established remote sensing techniques, and integration of these data with field mapping, geochronology and the sedimentary record, create new opportunities to understand orogenic evolution over these timescales. Timor Leste (East Timor) lies on the northern collisional boundary between continental crust from the Australian Plate and the Banda volcanic arc. GPS studies have indicated that the island of Timor is actively shortening. Field mapping and fault kinematic analysis of an emergent Pliocene marine sequence identifies gentle folding, overprinted by a predominance of NW-SE oriented dextral-normal faults and NE-SW oriented sinistral-normal faults that collectively bound large (5-20km2) bedrock massifs throughout the island. These fault systems intersect at non-Andersonian conjugate angles of approximately 120° and accommodate an estimated 20 km of orogen-parallel extension. Folding of Pliocene rocks in Timor may represent an early episode of contraction but the overall pattern of deformation is one of lateral crustal extrusion sub-parallel to the Banda Arc. Stratigraphic relationships suggest that extrusion began prior to 5.5 Ma, during and after initial uplift of the orogen. Sedimentological, geochemical and Nd isotope data indicate that the island of Timor was emergent and shedding terrigenous sediment into carbonate basins prior to 4.5 Ma. Synorogenic tectonic and sedimentary phases initiated almost synchronously across much of Timor Leste and <2 Myr before similar events in West Timor. An increase in plate coupling along this obliquely converging boundary, due to subduction of an outlying continental plateau at the Banda Trench, is proposed as a mechanism for uplift that accounts for orogen-parallel extension and early uplift of Timor Leste. Rapid bathymetric changes around Timor are likely to have played an important role in evolution of the Indonesian Seaway. The 2010 Mw 7.1 Darfield (Canterbury) earthquake in New Zealand was complex, involving multiple faults with strike-slip, reverse and normal displacements. Multi-temporal cadastral surveying and airborne light detection and ranging (LiDAR) surveys allowed surface deformation at the junction of three faults to be analyzed in this study in unprecedented detail. A nested, localized restraining stepover with contractional bulging was identified in an area with the overall fault structure of a releasing bend, highlighting the surface complexities that may develop in fault interaction zones during a single earthquake sequence. The earthquake also caused river avulsion and flooding in this area. Geomorphic investigations of these rivers prior to the earthquake identify plausible precursory patterns, including channel migration and narrowing. Comparison of the pre and post-earthquake geomorphology of the fault rupture also suggests that a subtle scarp or groove was present along much of the trace prior to the Darfield earthquake. Hydrogeology and well logs support a hypothesis of extended slip history and suggests that that the Selwyn River fan may be infilling a graben that has accumulated late Quaternary vertical slip of <30 m. Investigating fault behavior, geomorphic and sedimentary responses over a multitude of time-scales and at different study sites provides insights into fault interactions and orogenesis during single earthquakes and over millions of years of plate boundary deformation.

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Elkortbawi, Maya Roukos. "Insights into the Liquefaction Hazards in Napier and Hastings Based on the Assessment of Data from the 1931 Hawke's Bay, New Zealand, Earthquake." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78300.

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Hawke's Bay is situated on the east coast of the North Island of New Zealand and has experienced several earthquakes in the past during which liquefaction occurred. The 1931 Hawke's Bay earthquake is particularly interesting because it was the deadliest and one of the most damaging earthquakes in New Zealand's history. The study presented herein provides insights into the liquefaction hazards in Napier and Hastings based on the assessment of data from the 1931 Hawke's Bay event. Previous studies on the liquefaction hazard of the region have been performed, but the present work differs from those in that the liquefaction triggering and severity procedures are used to see if they can accurately predict observations from the 1931 event. Towards this end, the Cone Penetration Test (CPT)-based liquefaction triggering evaluations are used in liquefaction vulnerability assessment frameworks. It was found that liquefaction hazard in Napier is greater than Hastings. Additionally, Liquefaction Potential Index and Liquefaction Severity Number distributions across Napier and Hastings suggest that the analysis frameworks used are over-predicting the liquefaction hazard. This observation was reached through the comparison of predictions and 1931 post-earthquake observations. Possible causes for this over-prediction include the shortcomings in the analysis frameworks to account for the influence of non-liquefied layers in the profile on the severity of surficial liquefaction manifestations, shortcomings of the simplified liquefaction evaluation procedures to fully account for the depositional and compositional characteristics of the soil on liquefaction resistance, and the use of the assumption that the soils below the ground water table are fully saturated, which has been shown not to be the case at sites in Christchurch, New Zealand. The research community is still learning about earthquakes and liquefaction and this study demonstrates how historical earthquake accounts in a region can be used to assess the risk of the region from future earthquakes.
Master of Science

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26

Stafford, Peter James. "Engineering seismological studies and seismic design criteria for the Buller Region, South Island, New Zealand." Thesis, University of Canterbury. Civil Engineering, 2006. http://hdl.handle.net/10092/1078.

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This thesis addresses two fundamental topics in Engineering Seismology; the application of Probabilistic Seismic Hazard Analysis (PSHA) methodology, and the estimation of measures of Strong Ground Motion. These two topics, while being related, are presented as separate sections. In the first section, state-of-the-art PSHA methodologies are applied to various sites in the Buller Region, South Island, New Zealand. These sites are deemed critical to the maintenance of economic stability in the region. A fault-source based seismicity model is developed for the region that is consistent with the governing tectonic loading, and seismic moment release of the region. In attempting to ensure this consistency the apparent anomaly between the rates of activity dictated by deformation throughout the Quaternary, and rates of activity dictated by observed seismicity is addressed. Individual fault source activity is determined following the application of a Bayesian Inference procedure in which observed earthquake events are attributed to causative faults in the study region. The activity of fault sources, in general, is assumed to be governed by bounded power law behaviour. An exception is made for the Alpine Fault which is modelled as a purely characteristic source. The calculation of rates of exceedance of various ground motion indices is made using a combination of Poissonian and time-dependent earthquake occurrence models. The various ground motion indices for which rates of exceedance are determined include peak ground acceleration, ordinates of 5% damped Spectral Acceleration, and Arias Intensity. The total hazard determined for each of these ground motion measures is decomposed using a four dimensional disaggregation procedure. From this disaggregation procedure, design earthquake scenarios are specified for the sites that are considered. The second part of the thesis is concerned with the estimation of ground motion measures that are more informative than the existing scalar measures that are available for use in New Zealand. Models are developed for the prediction of Fourier Amplitude Spectra (FAS) as well as Arias Intensity for use in the New Zealand environment. The FAS model can be used to generate ground motion time histories for use in structural and geotechnical analyses. Arias Intensity has been shown to be an important strong motion measure due to its positive correlation with damage in short period structures as well as its utility in predicting the onset of liquefaction and landslides. The models are based upon the analysis of a dataset of New Zealand Strong Motion records as well as supplementary near field records from major overseas events. While the two measures of ground motion intensity are strongly related, different methods have been adopted in order to develop the models. As part of the methodology used for the FAS model, Monte Carlo simulation coupled with a simple ray tracing procedure is employed to estimate source spectra from various New Zealand earthquakes and, consequently, a magnitude - corner-frequency relationship is obtained. In general, the parameters of the predictive equations are determined using the most state-of-the-art mixed effects regression procedures.

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27

Paquet, Fabien. "Evolution morphostructurale des bassins de marge active en subduction : l'exemple du bassin avant arc de Hawke Bay en Nouvelle-Zélande = Morphostructural evolution of active subduction margin basins : the example of the Hawke Bay forearc basin, New Zealand /." Rennes : CNRS, Université de Rennes, 2008. http://library.canterbury.ac.nz/etd/adt-NZCU20080225.224857.

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Thesis (Ph. D.) -- l'Université de Rennes, 2007.
"Thése de Doctorat de l'Université de Rennes 1 réalisée en co-tutelle avec l'Université de Canterbury (Christchurch, Nouvelle-Zélande)." "Soutenue le 9 novembre 2007." Includes bibliographical references. Also available via WWW.

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28

Hill, Matthew P. "Evolution of quartz and calcite microstructures exhumed from deep brittle-ductile shear zones in the Southern Alps of New Zealand : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Geology /." ResearchArchive@Victoria e-Thesis, 2005. http://hdl.handle.net/10063/33.

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29

Mashiko, Naoto. "Comparative performance of ductile and damage protected bridge piers subjected to bi-directional earthquake attack." Thesis, University of Canterbury. Civil Engineering, 2006. http://hdl.handle.net/10092/1159.

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Incremental Dynamic Analysis (IDA) procedures are advanced and then applied to a quantitative risk assessment for bridge structures. This is achieved by combining IDA with site-dependent hazard-recurrence relations and damage outcomes. The IDA procedure is also developed as a way to select a critical earthquake motion record for a one-off destructive experiment. Three prototype bridge substructures are designed according to the loading and detailing requirements of New Zealand, Japan and Caltrans codes. From these designs 30 percent reduced scale specimens are constructed as part of an experimental investigation. The Pseudodynamic test is then to control on three specimens using the identified critical earthquake records. The results are presented in a probabilistic riskbased format. The differences in the seismic performance of the three different countries' design codes are examined. Each of these current seismic design codes strive for ductile behaviour of bridge substructures. Seismic response is expected to be resulting damage on structures, which may threaten post-earthquake serviceability. To overcome this major performance shortcoming, the seismic behaviour under bi-directional lateral loading is investigated for a bridge pier designed and constructed in accordance with Damage Avoidance principles. Due to the presence of steel armoured rocking interface at the base, it is demonstrated that damage can be avoided, but due to the lack of hysteresis it is necessary to add some supplemental damping. Experimental results of the armoured rocking pier under bi-directional loading are compared with a companion ductile design specimen.

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30

Paquet, Fabien. "Morphostructural evolution of active margin basins : the example of the Hawke Bay forearc basin, New Zealand : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Geology at the University of Canterbury /." Thesis, University of Canterbury. Geological Sciences, 2007. http://hdl.handle.net/10092/1474.

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Topography growth and sediment fluxes in active subduction margin settings are poorly understood. Geological record is often scarce or hardly accessible as a result of intensive deformation. The Hawke Bay forearc basin of the Hikurangi margin in New Zealand is well suited for studying morphstructural evolution. It is well preserved, partly emerged and affected by active tectonic deformation during Pleistocene stage for which we have well dated series and well-known climate and eustasy. The multidisciplinary approach, integrating offshore and onshore seismic interpretations, well and core data, geological mapping and sedimentological sections, results in the establishment of a detailed stratigraphic scheme for the last 1.1 Ma forearc basin fill. The stratigraphy shows a complex stack of 11 eustasy-driven depositional sequences of 20, 40 and 100 ka periodicity. These sequences are preserved in sub-basins that are bounded by active thrust structures. Each sequence is characterized by important changes of the paleoenvironment that evolves between the two extremes of the glacial maximum and the interglacial optimum. Thus, the Hawke Bay forearc domain shows segmentation in sub-basins separated by tectonic ridges during sea level lows that become submerged during sea level highs. Over 100 ka timescale, deformation along active structures together with isostasy are responsible of a progressive migration of sequence depocenters towards the arc within the sub-basins. Calculation of sediment volumes preserved for each of the 11 sequences allows the estimation of the sediment fluxes that transit throughout the forearc domain during the last 1.1 Ma. Fluxes vary from c. 3 to c. 6 Mt.a⁻¹. These long-term variations with 100 ka to 1 Ma timescale ranges are attributed to changes in the forearc domain tectonic configuration (strain rates and active structure distribution). They reflect the ability of sub-basin to retain sediments. Short-term variations of fluxes (<100 ka) observed within the last 150 ka are correlated to drastic Pleistocene climate changes that modified erosion rates in the drainage area. This implies a high sensitiveness and reactivity of the upstream area to environmental changes in terms of erosion and sediment transport. Such behaviour of the drainage basin is also illustrated by the important increase of sediment fluxes since the European settlement during the 18th century and the following deforestation.

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Chandratilake, (nee Weerasekara) Sonali Evanjali. "Spatial Modelling of Gastroenteritis Prevalence Following the February 22, 2011 Earthquake and Identification of Successful Factors Preventing Outbreaks at Emergency Centres." Thesis, University of Canterbury. Department of Geological Sciences, 2013. http://hdl.handle.net/10092/9185.

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The potential for a gastroenteritis outbreak in a post-earthquake environment may increase because of compromised infrastructure services, contaminated liquefaction (lateral spreading and surface ejecta), and the presence of gastroenteritis agents in the drinking water network. A population in a post-earthquake environment might be seriously affected by gastroenteritis because it has a short incubation period (about 10 hours). The potential for a gastroenteritis outbreak in a post-earthquake environment may increase because of compromised infrastructure services, contaminated liquefaction (lateral spreading and surface ejecta), and the presence of gastroenteritis agents in the drinking water network. A population in a post-earthquake environment might be seriously affected by gastroenteritis because it has a short incubation period (about 10 hours). The aim of this multidisciplinary research was to retrospectively analyse the gastroenteritis prevalence following the February 22, 2011 earthquake in Christchurch. The first focus was to assess whether earthquake-induced infrastructure damage, liquefaction, and gastroenteritis agents spatially explained the recorded gastroenteritis cases over the period of 35 days following the February 22, 2011 earthquake in Christchurch. The gastroenteritis agents considered in this study were Escherichia coli found in the drinking water supply (MPN/100mL) and Non-Compliant Free Associated Chlorine (FAC-NC) (less than <0.02mg/L). The second focus was the protocols that averted a gastroenteritis outbreak at three Emergency Centres (ECs): Burnside High School Emergency Centre (BEC); Cowles Stadium Emergency Centre (CEC); and Linwood High School Emergency Centre (LEC). Using a mixed-method approach, gastroenteritis point prevalence and the considered factors were quantitatively analysed. The qualitative analysis involved interviewing 30 EC staff members. The data was evaluated by adopting the Grounded Theory (GT) approach. Spatial analysis of considered factors showed that highly damaged CAUs were statistically clustered as demonstrated by Moran’s I statistic and hot spot analysis. Further modelling showed that gastroenteritis point prevalence clustering could not be fully explained by infrastructure damage alone, and other factors influenced the recorded gastroenteritis point prevalence. However, the results of this research suggest that there was a tenuous, indirect relationship between recorded gastroenteritis point prevalence and the considered factors: earthquake-induced infrastructure damage, liquefaction and FAC-NC. Two ECs were opened as part of the post-earthquake response in areas with severe infrastructure damage and liquefaction (BEC and CEC). The third EC (CEC) provided important lessons that were learnt from the previous September 4, 2010 earthquake, and implemented after the February 22, 2011 earthquake. Two types of interwoven themes identified: direct and indirect. The direct themes were preventive protocols and indirect themes included type of EC building (school or a sports stadium), and EC staff. The main limitations of the research were Modifiable Areal Units (MAUP), data detection, and memory loss. This research provides a practical method that can be adapted to assess gastroenteritis risk in a post-earthquake environment. Thus, this mixed method approach can be used in other disaster contexts to study gastroenteritis prevalence, and can serve as an appendage to the existing framework for assessing infectious diseases. Furthermore, the lessons learnt from qualitative analysis can inform the current infectious disease management plans, designed for a post-disaster response in New Zealand and internationally Using a mixed-method approach, gastroenteritis point prevalence and the considered factors were quantitatively analysed. A damage profile was created by amalgamating different types of damage for the considered factors for each Census Area Unit (CAU) in Christchurch. The damage profile enabled the application of a variety of statistical methods which included Moran’s I , Hot Spot (HS) analysis, Spearman’s Rho, and Besag–York–Mollié Model using a range of software. The qualitative analysis involved interviewing 30 EC staff members. The data was evaluated by adopting the Grounded Theory (GT) approach. Spatial analysis of considered factors showed that highly damaged CAUs were statistically clustered as demonstrated by Moran’s I statistic and hot spot analysis. Further modelling showed that gastroenteritis point prevalence clustering could not be fully explained by infrastructure damage alone, and other factors influenced the recorded gastroenteritis point prevalence. However, the results of this research suggest that there was a tenuous, indirect relationship between recorded gastroenteritis point prevalence and the considered factors: earthquake-induced infrastructure damage, liquefaction and FAC-NC. Two ECs were opened as part of the post-earthquake response in areas with severe infrastructure damage and liquefaction (BEC and CEC). The third EC (CEC) provided important lessons that were learnt from the previous September 4, 2010 earthquake, and implemented after the February 22, 2011 earthquake. The ECs were selected to represent the Christchurch area, and were situated where potential for gastroenteritis was high. BEC represented the western side of Christchurch; whilst, CEC and LEC represented the eastern side, where the potential for gastroenteritis was high according to the outputs of the quantitative spatial modelling. Qualitative analysis from the interviews at the ECs revealed that evacuees were arriving at the ECs with gastroenteritis-like symptoms. Participants believed that those symptoms did not originate at the ECs. Two types of interwoven themes identified: direct and indirect. The direct themes were preventive protocols that included prolific use of hand sanitisers; surveillance; and the services offered. Indirect themes included the EC layout, type of EC building (school or a sports stadium), and EC staff. Indirect themes governed the quality and sustainability of the direct themes implemented, which in turn averted gastroenteritis outbreaks at the ECs. The main limitations of the research were Modifiable Areal Units (MAUP), data detection, and memory loss. It was concluded that gastroenteritis point prevalence following the February 22, 2011 earthquake could not be solely explained by earthquake-induced infrastructure damage, liquefaction, and gastroenteritis causative agents alone. However, this research provides a practical method that can be adapted to assess gastroenteritis risk in a post-earthquake environment. Creating a damage profile for each CAU and using spatial data analysis can isolate vulnerable areas, and qualitative data analysis provides localised information. Thus, this mixed method approach can be used in other disaster contexts to study gastroenteritis prevalence, and can serve as an appendage to the existing framework for assessing infectious diseases. Furthermore, the lessons learnt from qualitative analysis can inform the current infectious disease management plans, designed for a post-disaster response in New Zealand and internationally.

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32

Russell, Frances Marion. "Semi-permanent zones of radar radial shear within the planetary boundary layer : observations and effects on high intensity precipitation in the wider Auckland region, New Zealand : a thesis submitted to the Victoria University of Wellington in partial fulfilment of the requirements for the degree of Master of Science in Geophysics /." ResearchArchive@Victoria e-Thesis, 2009. http://hdl.handle.net/10063/1215.

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33

Connolly, Maria Josephine. "The impacts of the Canterbury earthquakes on educational inequalities and achievement in Christchurch secondary schools." Thesis, University of Canterbury. Geography, 2013. http://hdl.handle.net/10092/7903.

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During 2010 and 2011, major earthquakes caused widespread damage and the deaths of 185 people in the city of Christchurch. Damaged school buildings resulted in state intervention which required amendment of the Education Act of 1989, and the development of ‘site sharing agreements’ in undamaged schools to cater for the needs of students whose schools had closed. An effective plan was also developed for student assessment through establishing an earthquake impaired derived grade process. Previous research into traditional explanations of educational inequalities in the United Kingdom, the United States of America, and New Zealand were reviewed through various processes within three educational inputs: the student, the school and the state. Research into the impacts of urban natural disasters on education and education inequalities found literature on post disaster education systems but nothing could be found that included performance data. The impacts of the Canterbury earthquakes on educational inequalities and achievement were analysed over 2009-2012. The baseline year was 2009, the year before the first earthquake, while 2012 is seen as the recovery year as no schools closed due to seismic events and there was no state intervention into the education of the region. National Certificate of Educational Achievement (NCEA) results levels 1-3 from thirty-four secondary schools in the greater Christchurch region were graphed and analysed. Regression analysis indicates; in 2009, educational inequalities existed with a strong positive relationship between a school’s decile rating and NCEA achievement. When schools were grouped into decile rankings (1-10) and their 2010 NCEA levels 1-3 results were compared with the previous year, the percentage of change indicates an overall lower NCEA achievement in 2010 across all deciles, but particularly in lower decile schools. By contrast, when 2011 NCEA results were compared with those of 2009, as a percentage of change, lower decile schools fared better. Non site sharing schools also achieved higher results than site sharing schools. State interventions, had however contributed towards student’s achieving national examinations and entry to university in 2011. When NCEA results for 2012 were compared to 2009 educational inequalities still exist, however in 2012 the positive relationship between decile rating and achievement is marginally weaker than in 2009. Human ethics approval was required to survey one Christchurch secondary school community of students (aged between 12 and 18), teachers and staff, parents and caregivers during October 2011. Participation was voluntary and without incentives, 154 completed questionnaires were received. The Canterbury earthquakes and aftershocks changed the lives of the research participants. This school community was displaced to another school due to the Christchurch earthquake on 22 February 2011. Research results are grouped under four geographical perspectives; spatial impacts, socio-economic impacts, displacement, and health and wellbeing. Further research possibilities include researching the lag effects from the Canterbury earthquakes on school age children.

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34

Villemure, Marlene. "Fine grained sediment clean-up in a modern urban environment." Thesis, University of Canterbury. Geological Sciences, 2013. http://hdl.handle.net/10092/8356.

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Fine grained sediment deposition in urban environments during natural hazard events can impact critical infrastructure and properties (urban terrain) leading to reduced social and economic function and potentially adverse public health effects. Therefore, clean-up of the sediments is required to minimise impacts and restore social and economic functionality as soon as possible. The strategies employed to manage and coordinate the clean-up significantly influence the speed, cost and quality of the clean-up operation. Additionally, the physical properties of the fine grained sediment affects the clean-up, transport, storage and future usage of the sediment. The goals of the research are to assess the resources, time and cost required for fine grained sediment clean-up in an urban environment following a disaster and to determine how the geotechnical properties of sediment will affect urban clean-up strategies. The thesis focuses on the impact of fine grained sediment (<1 mm) deposition from three liquefaction events during the Canterbury earthquake sequence (2010-2011) on residential suburbs and transport networks in Christchurch. It also presents how geotechnical properties of the material may affect clean-up strategies and methods by presenting geotechnical analysis of tephra material from the North Island of New Zealand. Finally, lessons for disaster response planning and decision making for clean-up of sediment in urban environments are presented. A series of semi-structured interviews of key stakeholders supported by relevant academic literature and media reports were used to record the clean-up operation coordination and management and to make a preliminary qualification of the Christchurch liquefaction ejecta clean-up (costs breakdown, time, volume, resources, coordination, planning and priorities). Further analysis of the costs and resources involved for better accuracy was required and so the analysis of Christchurch City Council road management database (RAMM) was done. In order to make a transition from general fine sediment clean-up to specific types of fine disaster sediment clean-up, adequate information about the material properties is required as they will define how the material will be handled, transported and stored. Laboratory analysis of young volcanic tephra from the New Zealand’s North Island was performed to identify their geotechnical properties (density, granulometry, plasticity, composition and angle of repose). The major findings of this research were that emergency planning and the use of the coordinated incident management system (CIMS) system during the emergency were important to facilitate rapid clean-up tasking, management of resources and ultimately recovery from widespread and voluminous liquefaction ejecta deposition in eastern Christchurch. A total estimated cost of approximately $NZ 40 million was calculated for the Christchurch City clean-up following the 2010-2011 Canterbury earthquake sequence with a partial cost of $NZ 12 million for the Southern part of the city, where up to 33% (418 km) of the road network was impacted by liquefaction ejecta and required clearing of the material following the 22 February 2011 earthquake. Over 500,000 tonnes of ejecta has been stockpiled at Burwood landfill for all three liquefaction inducing earthquake events. The average cost per kilometre for the event clean-up was $NZ 5,500/km (4 September 2010), $NZ 11,650/km (22 February 2011) and $NZ 11,185/km (13 June 2011). The duration of clean-up time of residential properties and the road network was approximately two to three months for each of the three liquefaction ejecta events; despite events volumes and spatial distribution of ejecta. Interviews and quantitative analysis of RAMM data revealed that the experience and knowledge gained from the Darfield earthquake (4 September 2010) clean-up increased the efficiency of the following Christchurch earthquake induced liquefaction ejecta clean-up events. Density, particle size, particle shape, clay content and moisture content, are the important geotechnical properties that need to be considered when planning for a clean-up method that incorporates collection, transport and disposal or storage. The geotechnical properties for the tephra samples were analysed to increase preparedness and reaction response of potentially affected North Island cities from possible product from the active volcanoes in their region. The geotechnical results from this study show that volcanic tephra could be used in road or construction material but the properties would have to be further investigated for a New Zealand context. Using fresh volcanic material in road, building or flood control construction requires good understanding of the material properties and precaution during design and construction to extra care, but if well planned, it can be economically beneficial.

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Gowan, Monica Elizabeth. "Self-Management of Disaster Risk and Uncertainty: The Role of Preventive Health in Building Disaster Resilience." Thesis, University of Canterbury. Health Sciences Centre, 2011. http://hdl.handle.net/10092/7605.

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One of the great challenges facing human systems today is how to prepare for, manage, and adapt successfully to the profound and rapid changes wreaked by disasters. Wellington, New Zealand, is a capital city at significant risk of devastating earthquake and tsunami, potentially requiring mass evacuations with little or short notice. Subsequent hardship and suffering due to widespread property damage and infrastructure failure could cause large areas of the Wellington Region to become uninhabitable for weeks to months. Previous research has shown that positive health and well-being are associated with disaster-resilient outcomes. Preventing adverse outcomes before disaster strikes, through developing strengths-based skill sets in health-protective attitudes and behaviours, is increasingly advocated in disaster research, practise, and management. This study hypothesised that well-being constructs involving an affective heuristic play vital roles in pathways to resilience as proximal determinants of health-protective behaviours. Specifically, this study examined the importance of health-related quality of life and subjective well-being in motivating evacuation preparedness, measured in a community sample (n=695) drawn from the general adult population of Wellington’s isolated eastern suburbs. Using a quantitative epidemiological approach, the study measured the prevalence of key quality of life indicators (physical and mental health, emotional well-being or “Sense of Coherence”, spiritual well-being, social well-being, and life satisfaction) using validated psychometric scales; analysed the strengths of association between these indicators and the level of evacuation preparedness at categorical and continuous levels of measurement; and tested the predictive power of the model to explain the variance in evacuation preparedness activity. This is the first study known to examine multi-dimensional positive health and global well-being as resilient processes for engaging in evacuation preparedness behaviour. A cross-sectional study design and quantitative survey were used to collect self-report data on the study variables; a postal questionnaire was fielded between November 2008 and March 2009 to a sampling frame developed through multi-stage cluster randomisation. The survey response rate was 28.5%, yielding a margin of error of +/- 3.8% with 95% confidence and 80% statistical power to detect a true correlation coefficient of 0.11 or greater. In addition to the primary study variables, data were collected on demographic and ancillary variables relating to contextual factors in the physical environment (risk perception of physical and personal vulnerability to disaster) and the social environment (through the construct of self-determination), and other measures of disaster preparedness. These data are reserved for future analyses. Results of correlational and regression analyses for the primary study variables show that Wellingtonians are highly individualistic in how their well-being influences their preparedness, and a majority are taking inadequate action to build their resilience to future disaster from earthquake- or tsunami-triggered evacuation. At a population level, the conceptual multi-dimensional model of health-related quality of life and global well-being tested in this study shows a positive association with evacuation preparedness at statistically significant levels. However, it must be emphasised that the strength of this relationship is weak, accounting for only 5-7% of the variability in evacuation preparedness. No single dimension of health-related quality of life or well-being stands out as a strong predictor of preparedness. The strongest associations for preparedness are in a positive direction for spiritual well-being, emotional well-being, and life satisfaction; all involve a sense of existential meaningfulness. Spiritual well-being is the only quality of life variable making a statistically significant unique contribution to explaining the variance observed in the regression models. Physical health status is weakly associated with preparedness in a negative direction at a continuous level of measurement. No association was found at statistically significant levels for mental health status and social well-being. These findings indicate that engaging in evacuation preparedness is a very complex, holistic, yet individualised decision-making process, and likely involves highly subjective considerations for what is personally relevant. Gender is not a factor. Those 18-24 years of age are least likely to prepare and evacuation preparedness increases with age. Multidimensional health and global well-being are important constructs to consider in disaster resilience for both pre-event and post-event timeframes. This work indicates a need for promoting self-management of risk and building resilience by incorporating a sense of personal meaning and importance into preparedness actions, and for future research into further understanding preparedness motivations.

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Silva, Luís Carlos Martins da. "Analysis of Christchurch Catholic Basilica, New Zealand." Master's thesis, 2013. http://hdl.handle.net/1822/30809.

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Dissertação de mestrado integrado em Engenharia Civil (área de especialização em Perfil de Estruturas e Geotecnia)
Cultural heritage buildings are structures that enclose a set of particular values which symbolically allow to become part of a given culture identity and continuity. Nowadays, the conservation interventions on these particular structures aim to retain its historic integrity, identity and symbolism by taking into account centuries of ideological evolution, related to aesthetic and technical issues. The interventions in cultural heritage buildings should only be taken after a careful analysis, which includes a diagnosis, safety assessment and the design of possible solutions. Despite the need for some conservation interventions due to lack of maintenance and progressive deterioration, situations of sudden destruction of cultural heritage buildings deserves a special reflection. A numerical model is invariably a valuable tool to assess the structural behavior of these buildings and to influence the final act decision. The present study case is the Christchurch Catholic Basilica, also known as Cathedral of the Blessed Sacrament. It is located in New Zealand and is listed as category I heritage in New Zealand – International or National significance. The four earthquakes events in an approximate period of nine months (September 2010 to June 2011) led to a progressive damage and local collapses. In order to study its structural behavior, a seismic analysis was carried out. The seismic assessment of the Cathedral involved the preparation and calibration of a tri-dimensional numerical model based on the Finite Element Method. Two models were prepared, an undamaged and a damaged one once the structure was already damaged at the time of the dynamic identification tests. The calibration process was not accomplished once the dynamic properties obtained from the dynamic identification tests do not fit well with the numerical results. The main cause is the interior damage that was not inserted (it is unknown). In order to evaluate the dynamic behavior of the Cathedral were carried out pushover analyses proportional to the mass in each direction. These analyses allowed collecting the damage patterns, the vulnerable elements and the ductile behavior using capacity curves. Having in account this information a comparison between the numerical and real behavior was affordable and a reasonable agreement was obtained.
Edifícios pertencentes ao Património cultural são estruturas que integram um grupo particular de valores intangíveis que simbolicamente possibilitam que estas façam parte da identidade e continuidade de uma dada cultura. As intervenções de conservação têm em conta, atualmente, séculos de evolução ideológica relacionada com aspetos estéticos e técnicos que procuram reter a sua integridade histórica, identidade e simbolismo. A intervenção sobre este tipo de estruturas deve ser realizada após um estudo criterioso, que inclui um diagnóstico, avaliação da segurança estrutural e desenvolvimento de possíveis soluções. Apesar da necessidade de conservação de estruturas pertences ao património cultural devido à falta de manutenção e consequente progressiva deterioração, situações em que ocorre o seu colapso súbito merecem uma reflexão especial. Um modelo numérico é invariavelmente uma ferramenta valiosa para avaliar o seu comportamento estrutural e influenciar a tomada de decisão final. O presente estudo trata do caso da Basílica Católica de Christchurch, também conhecida como Catedral do Sagrado Sacramento. Está localizada na Nova Zelândia e consta na categoria I da lista do património da Nova Zelândia – importância Nacional e Internacional. Os quatro eventos sísmicos num período aproximado de nove meses (Setembro de 2010 até Junho de 2011) levou a um dano progressivo e colapsos locais. Objetivando o estudo do comportamento estrutural foi realizada uma análise sísmica. A avaliação sísmica da Catedral envolveu a preparação de um modelo numérico tridimensional através do método de elementos finitos. Uma vez que a estrutura já se apresentava danificada, aquando os ensaios de identificação dinâmica, dois modelos foram preparados: um com dano e outro sem dano inserido. A calibração do modelo não foi conseguida uma vez que o dano interior, não inserido por não ser conhecido, impossibilitou um ajuste correto das propriedades dinâmicas obtidas nos testes de identificação dinâmica. Para avaliar o comportamento dinâmico da Catedral foram realizadas análises pushover proporcionais à sua massa em cada direção. Estas análises permitiram coletar o dano, os elementos vulneráveis e a ductilidade da estrutura através de curvas de capacidade. Tendo em conta esta informação, uma comparação entre o comportamento real e numérico foi possível, tendo sido obtido uma concordância razoável entre os mesmos.

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Martin, Jonathan Grant. "Measuring liquefaction-induced deformation from optical satellite imagery." Thesis, 2014. http://hdl.handle.net/2152/25858.

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Liquefaction-induced deformations associated with lateral spreading represent a significant hazard that can cause substantial damage during earthquakes. The ability to accurately predict lateral-spreading displacement is hampered by a lack of field data from previous earthquakes. Remote sensing via optical image correlation can fill this gap and provide data regarding liquefaction-induced lateral spreading displacements. In this thesis, deformations from three earthquakes (2010 Darfield, February 2011 Christchurch, and 2011 Tohoku Earthquakes) are measured using optical image correlation applied to 0.5-m resolution satellite imagery. The resulting deformations from optical image correlation are compared to the geologic conditions, as well as field observations and measurements of liquefaction. Measurements from optical image correlation are found to have a precision within 0.40 m in all three cases, and results agree well with field measurements.
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