Old churches and earthquakes do not mix well.
GNS seismologists explain why the Darfield and Christchurch earthquakes were so damaging and 'punchy'
Rodger Bates is a farmer from near Darfield.
A video of interviews with Kaiapoi residents about their the 4 September 2010 earthquake. Kaiapoi was one of the worst-affected areas following the earthquake which was centred in Darfield.
Photograph captioned by Fairfax, "Earthquake damage to roads near Darfield".
Photograph captioned by Fairfax, "Earthquake damage to roads near Darfield".
Photograph captioned by Fairfax, "Earthquake damage to roads near Darfield".
Photograph captioned by Fairfax, "Earthquake damage to roads near Darfield".
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
Toppled grain silos on the outskirts of Darfield near the epicentre of the magnitude 7,1 earthquake that struck on Saturday 4 September 2010.
On the way to Darfield to locate the faultline where the tectonic plates slipped, causing the magnitude 7.1 earthquake on Saturday 4 September 2010.
On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Unreinforced masonry buildings also suffered extensive damage throughout the region. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, an intensive geotechnical reconnaissance was conducted to capture evidence and perishable data from this event. This paper summarizes the observations and preliminary findings from this early reconnaissance work.
Three seismologists from GeoNet reflect on the decade of big earthquakes that began 10 years ago with the Darfield earthquake in Canterbury.
A video about the 4 September 2010 earthquake, produced for the anniversary of the earthquake. The video includes footage of the earthquake damage to the Christchurch city centre, Darfield, Rolleston, and Hororata. It also includes footage of diggers clearing stock in the Canterbury Brewery on St Asaph Street, engineers checking buildings in town, and a fire on Worcester Street.
Photograph captioned by Fairfax, "Darfield man Craig Smith with earthquake damage to farm paddocks near Christchurch".
This paper presents the preliminary findings of a study on the resilience and recovery of organisations following the Darfield earthquake in New Zealand on 4 September 2010. Sampling included organisations proximal and distal to the fault trace, organisations located within central business districts, and organisations from seven diverse industry sectors. The research captured information on the challenges to, the impacts on, and the reflections of the organisations in the first months of recovery. Organisations in central business districts and in the hospitality sector were most likely to close while organisations that had perishable stock and livestock were more heavily reliant on critical services. Staff well-being, cash flow, and customer loss were major concerns for organisations across all sectors. For all organisations, the most helpful factors in mitigating the effects of the earthquake to be their relationship with staff, the design and type of buildings, and critical service continuity or swift reinstatement of services.
The objective of this study is to examine the influence of near-fault motions on liquefaction triggering in Christchurch and neighboring towns during the 2010-2011 Canterbury earthquake sequence (CES). The CES began with the 4 September 2010, Mw7.1 Darfield earthquake and included up to ten events that triggered liquefaction. However, most notably, widespread liquefaction was induced by the Darfield earthquake and the Mw6.2, 22 February 2011 Christchurch earthquake. Of particular relevance to this study is the forward directivity effects that were prevalent in the motions recorded during the Darfield earthquake, and to a much lesser extent, during the Christchurch earthquake. A 2D variant of the Richart-Newmark fatigue theory was used to compute the equivalent number of cycles (neq) for the ground motions, where volumetric strain was used as the damage metric. This study is unique because it considers the contribution and phasing of both the fault-normal and fault-parallel components of motion on neq and the magnitude scaling factor (MSF). It was found that when the fault-normal and fault-parallel motions were treated individually, the former yielded a lower neq than the latter. Additionally, when the combined effects of fault-normal and fault-parallel components were considered, it was found that the MSF were higher than those commonly used. This implies that motions containing near-fault effects are less demanding on the soil than motions that do not. This may be one of several factors that resulted in less severe liquefaction occurring during the Darfield earthquake than the Christchurch earthquake.
Photograph captioned by Fairfax, "Di and Craig Roberts refuse to look at their earthquake-damaged house near Darfield".
A team of earthquake geologists, seismologists and engineering seismologists from GNS Science, NIWA, University of Canterbury, and Victoria University of Wellington have collectively produced an update of the 2002 national probabilistic seismic hazard (PSH) model for New Zealand. The new model incorporates over 200 new onshore and offshore fault sources, and utilises newly developed New Zealand-based scaling relationships and methods for the parameterisation of the fault and subduction interface sources. The background seismicity model has also been updated to include new seismicity data, a new seismicity regionalisation, and improved methodology for calculation of the seismicity parameters. Background seismicity models allow for the occurrence of earthquakes away from the known fault sources, and are typically modelled as a grid of earthquake sources with rate parameters assigned from the historical seismicity catalogue. The Greendale Fault, which ruptured during the M7.1, 4 September 2010 Darfield earthquake, was unknown prior to the earthquake. However, the earthquake was to some extent accounted for in the PSH model. The maximum magnitude assumed in the background seismicity model for the area of the earthquake is 7.2 (larger than the Darfield event), but the location and geometry of the fault are not represented. Deaggregations of the PSH model for Christchurch at return periods of 500 years and above show that M7-7.5 fault and background source-derived earthquakes at distances less than 40 km are important contributors to the hazard. Therefore, earthquakes similar to the Darfield event feature prominently in the PSH model, even though the Greendale Fault was not an explicit model input.
On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage occurred to unreinforced masonry buildings throughout the region during the mainshock and subsequent large aftershocks. Particularly extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, a geotechnical reconnaissance was conducted over a period of six days (10–15 September 2010) by a team of geotechnical/earthquake engineers and geologists from New Zealand and USA (GEER team: Geo-engineering Extreme Event Reconnaissance). JGS (Japanese Geotechnical Society) members from Japan also participated in the reconnaissance team from 13 to 15 September 2010. The NZ, GEER and JGS members worked as one team and shared resources, information and logistics in order to conduct thorough and most efficient reconnaissance covering a large area over a very limited time period. This report summarises the key evidence and findings from the reconnaissance.
Photograph captioned by Fairfax, "Canterbury earthquake. Amy Taylor from Darfield photographs the damage to St Johns church in Hororata".
A video of an interview with Tania and Paddy McKay from Darfield about how their lives have changed a year after the 4 September 2010 earthquake. This video is part of The Press's 'One Year On: September 4, 2010' series.