A photograph of University of Canterbury Geology student Matt Cockcroft using ground penetrating radar (GPR) to survey land on the Greendale fault line.
Photograph captioned by Fairfax, "Murray Rowlands and Carly Sluys from Federated Farmers look at the fault line west of Burnham after Saturday's earthquake".
This paper provides a photographic tour of the ground-surface rupture features of the Greendale Fault, formed during the 4th September 2010 Darfield Earthquake. The fault, previously unknown, produced at least 29.5 km of strike-slip surface deformation of right-lateral (dextral) sense. Deformation, spread over a zone between 30 and 300 m wide, consisted mostly of horizontal flexure with subsidiary discrete shears, the latter only prominent where overall displacement across the zone exceeded about 1.5 m. A remarkable feature of this event was its location in an intensively farmed landscape, where a multitude of straight markers, such as fences, roads and ditches, allowed precise measurements of offsets, and permitted well-defined limits to be placed on the length and widths of the surface rupture deformation.
Photograph captioned by Fairfax, "Aerial shot of the fault line that ruptured causing Saturday's 7.1 earthquake. A deer fenceline destroyed by the quake".
Photograph captioned by Fairfax, "Aerial shot of the fault line that ruptured, causing Saturday's 7.1 earthquake. Track, fence and hedge showing horizontal displacement".
PDF slides from a presentation given by Dr. Thomas Wilson from the UC Geology department on 27 October 2010.
A photograph of University of Canterbury Geology students Zach Whitman and Dewiyani Bealing using ground penetrating radar equipment to survey land on the Greendale fault line.
Photograph captioned by Fairfax, "Visiting professor Kevin Furlong from Penn State University in the USA looks at the fault line west of Burnham after Saturday's earthquake".
Photograph captioned by Fairfax, "Visiting professor Kevin Furlong from Penn State University in the USA looks at the fault line west of Burnham after Saturday's earthquake".
The 2010–2011 Canterbury earthquakes and their aftermath have been described by the Human Rights Commission as one of New Zealand's greatest contemporary human rights challenges. This article documents the shortcomings in the realisation of the right to housing in post-quake Canterbury for homeowners, tenants and the homeless. The article then considers what these shortcomings tell us about New Zealand's overall human rights framework, suggesting that the ongoing and seemingly intractable nature of these issues and the apparent inability to resolve them indicate an underlying fragility implicit in New Zealand's framework for dealing with the consequences of a large-scale natural disaster. The article concludes that there is a need for a comprehensive human rights-based approach to disaster preparedness, response and recovery in New Zealand.
A photograph of University of Canterbury Geology staff and students using a dynamic cone penetrometer to measure soil strength of a paddock on the Greendale fault line.
A photograph of a sign in Sophie's Café on Papanui Road. The first line of the sign reads, "Yes toilet is outside and yes its not our fault".
A photograph of University of Canterbury Geology students using ground penetrating radar equipment to survey land on the Greendale fault line. From left: Matt Cockcroft, Zach Whitman and Dewiyani Bealing.
A photograph of University of Canterbury Geology students using ground penetrating radar equipment to survey land on the Greendale fault line. From left: Matt Cockcroft, Zach Whitman and Dewiyani Bealing.
A photograph of University of Canterbury Geology students using ground penetrating radar equipment to survey land on the Greendale fault line. From left: Matt Cockcroft, Zach Whitman and Dewiyani Bealing.
Our poster will present on-going QuakeCoRE-founded work on strong motion seismology for Dunedin-Mosgiel area, focusing on ground motion simulations for Dunedin Central Business District (CBD). Source modelling and ground motion simulations are being carried out using the SCEC (Southern California Earthquakes Center) Broad Band simulation Platform (BBP). The platform computes broadband (0-10 Hz) seismograms for earthquakes and was first implemented at the University of Otago in 2016. As large earthquakes has not been experienced in Dunedin in the time of period of instrumental recording, user-specified scenario simulations are of great value. The Akatore Fault, the most active fault in Otago and closest major fault to Dunedin, is the source focused on in the present study. Simulations for various Akatore Fault source scenarios are run and presented. Path and site effects are key components considered in the simulation process. A 1D shear wave velocity profile is required by SCEC BBP, and this is being generated to represent the Akatore-to-CBD path and site within the BBP. A 3D shear velocity model, with high resolution within Dunedin CBD, is being developed in parallel with this study (see Sangster et al. poster). This model will be the basis for developing a 3D shear wave velocity model for greater Dunedin-Mosgiel area for future ground motion simulations, using Canterbury software (currently under development).
Photograph captioned by Fairfax, "Pilar Villamor, an earthquake scientist with GNS, near the end of the earthquake fault, which has caused a dip in this paddock, leading to flooding".
A photograph of University of Canterbury Geology staff and students using ground penetrating radar (GPR) to survey land on the Greendale fault line. From left: Thomas Wilson, Zach Whitman and Matt Cockcroft.
© 2017 The Royal Society of New Zealand. This paper discusses simulated ground motion intensity, and its underlying modelling assumptions, for great earthquakes on the Alpine Fault. The simulations utilise the latest understanding of wave propagation physics, kinematic earthquake rupture descriptions and the three-dimensional nature of the Earth's crust in the South Island of New Zealand. The effect of hypocentre location is explicitly examined, which is found to lead to significant differences in ground motion intensities (quantified in the form of peak ground velocity, PGV) over the northern half and southwest of the South Island. Comparison with previously adopted empirical ground motion models also illustrates that the simulations, which explicitly model rupture directivity and basin-generated surface waves, lead to notably larger PGV amplitudes than the empirical predictions in the northern half of the South Island and Canterbury. The simulations performed in this paper have been adopted, as one possible ground motion prediction, in the ‘Project AF8’ Civil Defence Emergency Management exercise scenario. The similarity of the modelled ground motion features with those observed in recent worldwide earthquakes as well as similar simulations in other regions, and the notably higher simulated amplitudes than those from empirical predictions, may warrant a re-examination of regional impact assessments for major Alpine Fault earthquakes.
Surface rupture of the previously unrecognised Greendale Fault extended west-east for ~30 km across alluvial plains west of Christchurch, New Zealand, during the Mw 7.1 Darfield (Canterbury) earthquake of September 2010. Surface rupture displacement was predominantly dextral strike-slip, averaging ~2.5 m, with maxima of ~5 m. Vertical displacement was generally less than 0.75 m. The surface rupture deformation zone ranged in width from ~30 to 300 m, and comprised discrete shears, localised bulges and, primarily, horizontal dextral flexure. About a dozen buildings, mainly single-storey houses and farm sheds, were affected by surface rupture, but none collapsed, largely because most of the buildings were relatively flexible and resilient timber-framed structures and also because deformation was distributed over a relatively wide zone. There were, however, notable differences in the respective performances of the buildings. Houses with only lightly-reinforced concrete slab foundations suffered moderate to severe structural and non-structural damage. Three other buildings performed more favourably: one had a robust concrete slab foundation, another had a shallow-seated pile foundation that isolated ground deformation from the superstructure, and the third had a structural system that enabled the house to tilt and rotate as a rigid body. Roads, power lines, underground pipes, and fences were also deformed by surface fault rupture and suffered damage commensurate with the type of feature, its orientation to the fault, and the amount, sense and width of surface rupture deformation.
Text at top left reads 'Daft things our forefathers did The cartoon shows several nineteenth century gentlemen observing 'volcanic cones', a 'swamp' and 'faultlines underneath' and deciding to build a city. Context - Specifically the Christchurch earthquakes of 4 September 2010 and 22 February 2011 but generally the way many New Zealand cities are built on or near volcanoes, faultlines and swamps. Quantity: 1 digital cartoon(s).
Structures of the Lowry Peaks Range - Waikari Valley district are complex. The majority comprise three members of a predominantly WSW -ENE striking major northwards-directed, leading edge imbricate thrust system, with associated angular, asymmetric fault-propagation folds. This system forms anomalously within a large NESW trending belt of structures characterising the entire east coast of north Canterbury, both onshore and offshore and terminates westwards against N-S striking, east facing fold-fault zone. The objectives of this study address the origin, geometry and kinematics of the interaction between these diversely trending systems. Stratigraphy and small-scale structures denote three periods of deformation, namely: i) Middle Cretaceous deformation of the basement rocks, ii) weak Middle Oligocene deformation associated with the inception of the plate boundary through the South Island, and iii) major Pliocene - Recent deformation that formed the majority of the above-mentioned structures. Stress tensor analyses within competent basement and limestone cover rocks suggest two sets of sub-horizontal compression, NE-SW and NW-SE, the former likely to relate to a localised earlier period of deformation, now overprinted by the latter. NW-SE oriented sub-horizontal compression correlates well with results from other parts of north Canterbury. The result of NW-SE compression on the W-E to WSW-ENE striking structures is a large component of oblique motion, which is manifest in four ways: i) movement on two, differently oriented splays rather than a single fault strand, ii) the development of a sinuous trace for a number of the major folds, whereby the ends are oriented normal to the compression direction, the centres parallel to the strike of the faults, iii) the development of a number of cross-folds, striking NNE-SSW and iv) the apparently recent development of a strike-slip component on at least one of the major thrust faults. The origin of the W-E, or WSW-ENE striking structures may be reactivation of Late Cretaceous faults, stratigraphic evidence for the existence of a "structural high" (the Hurunui High) over the majority of the area in the Late Cretaceous to Early Eocene times suggests the formation of a W-E trending horst structure, with a corresponding asymmetric graben to the south. The junction of WSW-ENE trending structures with N-S trending structures to the west centres on an alluvial-filled depression, Waikari Flat, into which the structures of the WSW-ENE trending imbricate thrust system plunge, locally curling to the SW at their ends to link with N-S trending structures to the south. Roof thrusting on two orientations, W-E and N-S, towards to SE is currently occurring above these structures. Currently the area is not highly seismically active, although a magnitude ~6.4 Ms earthquake in historic times has been recorded. The effects of tectonics on the drainage of the area does suggest that the majority of the systems, are still potentially active, albeit moving at a comparatively slow rate. The majority of the recent motion appears to be concentrated on the roof-thrusting occurring in Waikari Flat, and uplift along the Lowry Peaks Fault System. Increasing amounts of secondary movement on back-thrusts and cross fractures is also implied for western ends of the major imbricate thrust system. In contrast, the southern-most fault system appears to be largely sustaining dextral strike-slip motion, with some local folding in central portions.
Ground heaving on the faultline from which the Saturday 4 September 2010 earthquake originated.
On 4 September 2010, a 7.1 magnitude earthquake struck near Darfield, 40 kilometres west of Christchurch, New Zealand. The quake caused significant damage to land and buildings nearby, with damage extending to Christchurch city. On 22 February 2011, a 6.3 magnitude earthquake struck Christchurch, causing extensive and significant damage across the city and with the loss of 185 lives. Years on from these events, occasional large aftershocks continue to shake the region. Two main entomological collections were situated within close proximity to the 2010/11 Canterbury earthquakes. The Lincoln University Entomology Research Collection, which is housed on the 5th floor of a 7 storey building, was 27.5 km from the 2010 Darfield earthquake epicentre. The Canterbury Museum Entomology Collection, which is housed in the basement of a multi-storeyed heritage building, was 10 km from the 2011 Christchurch earthquake epicentre. We discuss the impacts of the earthquakes on these collections, the causes of the damage to the specimens and facilities, and subsequent efforts that were made to prevent further damage in the event of future seismic events. We also discuss the wider need for preparedness against the risks posed by natural disasters and other catastrophic events.
We have a leaked report which details critical earthquake faults in a new high rise building in Christchurch. A review finds bullies in Parliament but doesn't say who they are. And a Muslim community advocate welcomes the laying of terrorism charges against the Christchurch gunman.
The ground literally opened up! On the previously unknown faultline along which the Saturday 4 September 2010 earthquake originated.
The ground literally opened up! On the previously unknown faultline along which the Saturday 4 September 2010 earthquake originated.
The ground literally opened up! On the previously unknown faultline along which the Saturday 4 September 2010 earthquake originated.
The ground literally opened up! On the previously unknown faultline along which the Saturday 4 September 2010 earthquake originated.
If you look very closely, running from the nearest right desk to the second desk on the left hand side, you can see my 'fault-line', - the crack that runs the length of the classroom under the lino.