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This paper investigates the impact of an earthquake on households' perception of the seismic risks associated with residential locations—and, consequently, the impact of this change in perceptions on real estate prices—by performing revealed preference analysis on a unique data set of house prices and damage claims after the 2010/2011 Canterbury earthquake in New Zealand. We show that both informational and heuristic obstacles could have caused households to underestimate location earthquake risk before the quake and overreact to it after the quake. Our findings highlight the importance of quake-related information for seismic risk management and are robust to households' risk preferences in neighborhood propensity score matching. [ABSTRACT FROM AUTHOR]

Glazing damage reported following recent New Zealand earthquakes, i.e. the 2011 (Mw 6.2) Christchurch and 2016 (Mw 7.8) Kaikōura earthquakes, exceeded what would be expected from glazing designed or tested to council's compliance pathways, which indicates improvements are required to the existing pathways. Two series of proof-of-concept tests were conducted to induce simulated seismic actions on glazing specimens to better understand the failure mechanisms of gasket dislodgement, cracks in the glazing, and dislodgement of the glass to improve existing compliance tests and engineering design. The Series 1 tests consisted of 6 mm annealed window glass clamped in a steel frame with the load applied to the glazing with hydraulic jacks positioned in three distinct positions. The Series 2 tests consisted of a reverse cyclic loading on a commercial window located near the bottom of a direct-fixed rainscreen specimen. The test results were used to formulate a method that could predict the likelihood of seismic damage to glazing systems, improve compliance pathways, and is useful as a forensic predictive tool. [ABSTRACT FROM AUTHOR]

Earthquakes are insured in high‐risk high‐income countries only if the public sector is involved. Prototypical examples are the insurance schemes in California (United States), Japan, and New Zealand, but each is structured differently. This paper examines these variations using a concrete case study: the sequence of earthquakes in Christchurch, New Zealand, in 2010–11—the most heavily insured seismic event in history. It assesses what would have been the outcome had the Christchurch insurance system been different, focusing on the California Earthquake Authority (CEA) programme and Japan Earthquake Reinsurance (JER). Overall, the aggregate cost of the earthquake to the New Zealand public insurer (Earthquake Commission) was USD 6.2 billion. If a similar‐sized disaster had occurred in Japan and California, homeowners would have received around USD 1.6 billion and USD 0.7 billion, respectively. This paper describes the distributive and spatial patterns of these scenarios and discusses some key policy questions that emerge from this comparison. [ABSTRACT FROM AUTHOR]

Controlled and natural source seismic data are used to build a 3‐D P wave model for southern North Island, New Zealand, where the Pacific Plate subducts beneath the Australian Plate at a rate of ~41 mm/year. Our analysis reveals an abrupt along‐strike transition in overthrusting plate structure within Cook Strait. Contrasts in properties (Vp, Vp/Vs, and Qs) likely reflects the degree of deformation in the Australian Plate, where the Alpine‐Wairau and Awatere Faults mark the northern boundary of a terrane that has undergone >50° of clockwise vertical‐axis rotation since the early Miocene. Heterogeneity of the crustal transition is likely associated with changes in frictional and elastic properties that may impact elastic stress accumulation and inhibit southward propagation of megathrust earthquakes. Low connectivity of faults in Cook Strait is consistent with the heterogeneity we observe and may promote complex earthquake triggering by lateral stress loading during earthquakes or slow slip events. Plain Language Summary: Subduction zones produce the largest earthquakes and tsunami on Earth and knowledge of structures and physical rock properties at subducting margins will inform how and where strain is accumulated, as well as how stress is relieved. Combined information from earthquakes, seismic data, gravity observations, and geological mapping constrain a new 3‐D subduction zone image at the southern Hikurangi margin, central New Zealand, where the Pacific Plate dives beneath the Australian Plate. The image reveals an abrupt inherited along‐strike transition in the upper Australian Plate structure through Cook Strait. The region is notable because the 2016 magnitude 7.8 Kaikōura earthquake ruptured more than a dozen faults in northern South Island, south of Cook Strait, and triggered large afterslip on the subduction interface. However, the Kaikōura earthquake afterslip did not extend across the Cook Strait transition, into the southern North Island, where the subduction interface is currently strongly coupled or locked. Our work offers new insights suggesting that structure and frictional properties of the overthrusting upper plate might also limit the lateral extent of rupture in future earthquakes on the southern Hikurangi subduction zone. Key Points: The 3‐D velocity images and residual gravity anomalies reveal along‐strike transition in upper plate structure along southern Hikurangi marginTransition marks the northern boundary of a tectonic terrane that has undergone clockwise vertical‐axis rotation since early MioceneThe structure and frictional properties of the upper plate may control megathrust coupling and seismogenic behavior in southern Hikurangi [ABSTRACT FROM AUTHOR]

An earthquake with Richter magnitude 6.3 struck in the vicinity of Christchurch in New Zealand. It was the second largest seismic event to strike the area within a short time interval. Although of relatively small magnitude, the quake was extremely destructive as it struck much closer to the city than the previous earthquake of 4 September 2010. More than 180 people lost their lives. The earthquake occurred onshore, so there was no tsunami generated. Loss of power at the tide gauge of Lyttelton Port of Christchurch failed to record any wave activity. The GeoNet site at Sumner Head, which is located on the open coast, registered some longer period waves, but these were the result of weather related generation and not of seismic origin. According to eyewitnesses, the earthquake's motions were mild in Aoraki Mt. Cook National Park on the western side of New Zealand's South Island, but the shaking triggered an icefall off the end of the Tasman Glacier's lake and generated significant tsunami waves with an initial wall of water that was 50 or 60 meters high, but up to 3.5 meters high along its shores. The present study assesses the tectonic stresses and seismicity of the Marlborough fault system along the northern part of South Island, and briefly evaluates the potential of future tsunami generation from earthquakes that may be generated near New Zealand's Hikurangi Trough, that may also impact the coasts of South Island as well as the coastlines near the City of Wellington on North Island. [ABSTRACT FROM AUTHOR]

The post-earthquake damage assessment represents the first step after an emergency to support not only the safety of people, but also the preservation of buildings through the realization of prompt and effective provisional interventions. The issue is of particular relevance in case of monumental assets such as churches that are the focus of the paper. In Italy, since 1997 the post-earthquake damage assessment of churches has been carried out using a specific form, which was formally approved in 2001 by the Italian Civil Protection. Being the most advanced tool available in the literature within this specific field, the Italian form has been widely used also internationally. It follows the approach based on the decomposition of the church into macroelements. Although the latter has found wide confirmation through the interpretation of real damage, some critical issues were raised in relation to the versatility of the form and the reliability of the damage index that the approach provides. The post-earthquake damage assessment of 48 unreinforced masonry churches located in New Zealand, hit by the Canterbury earthquake sequence 2010–2011, represented an unprecedented opportunity, at international level, to investigate and to address the aforementioned issues. Starting from some weaknesses of the actual form, a new proposal (named CAF-D) for the damage assessment of unreinforced masonry churches has been developed and presented in the paper. The new form is still based on the macroelement approach, but it considers, in a separate way, the macroelements and the seismic damage modes they might develop, thus overcoming the limitation of the fixed number of damage mechanisms identified a priori by the current Italian form. The more reliable damage assessment approach that such form aims to achieve is the prelude to the development of a specific vulnerability model, derived by combining an empirical and an expert elicitation approach. A specific vulnerability model developed for New Zealand churches, derived by implementing the proposed CAF-D form and the related damage assessment procedure, is presented in the last part of the paper. [ABSTRACT FROM AUTHOR]

Learning after a disaster is crucial in creating more resilient places. However, many societies are repeatedly overwhelmed by disasters. This can be because of missed opportunities to learn in post‐disaster settings or because of actions implemented that seem to be highly relevant to recovery in the short term, but potentially constrain aspirations in the longer term. This paper assesses learning processes among state and non‐state actors and the ways in which these are bridged and scaled up to wider improvements in governance. Aiming to enrich understanding of post‐disaster learning, it explores different actors' response actions after the earthquakes in Christchurch, New Zealand, in 2010 and 2011. On the one hand, 'learning by doing' is occurring, yet, on the other hand, systemic learning is hindered by mismatches between top‐down steering and bottom‐up initiatives. The study concludes that better linking and synergising of learning processes among different levels is vital for enhancing resilience in post‐disaster societies. [ABSTRACT FROM AUTHOR]

Whenever fellow humans suffer due to natural catastrophes, we have a duty to help them. This duty is not only acknowledged in moral theory but also expressed in ordinary people's reactions to phenomena such as tsunamis, hurricanes, and earthquakes. Despite being widely acknowledged, this duty is also widely disputed: some believe it is a matter of justice, others a matter of charity. Although central to debates in international political theory, the distinction between justice and charity is hardly ever systematically drawn. To fill this gap in the literature, I consider three accounts of this distinction- the 'agent-based,' the 'recipient-based,' and the 'mixed' view-and argue that they are all unsatisfactory. I then offer a fourth alternative, the 'autonomy' view, which successfully overcomes the difficulties affecting its rivals. I conclude by considering the implications of this view for the moral grounds of disaster relief in earthquake-stricken Haiti, New Zealand, and Japan. [ABSTRACT FROM AUTHOR]

The article presents the author's reflections on the challenges facing city and town planning officials in regard to natural disaster reconstruction. The author outlines several conceptual issues involved with pre-disaster planning and post-disaster emergency management. The author's experiences working in Japan after the 2011 earthquake are cited as a case example along with mention of the 2011 New Zealand quake.

The article discusses the factors that contribute to the downward trend of the International Security Index (iSi) from November 2010 to April 2011. It states that iSi has declined from 2,945 points in January 2011 to 2,809 in April 2011. It notes that the turmoil in the Middle East and North America had implications for regional and global security. It notes that the earthquakes in New Zealand and Japan and the destruction of Japan's nuclear power plant pushed the iSi index down.

Disaster related research has its own interdisciplinary perspectives connected to the disaster cycle (response, recovery, prevention, and preparedness). This special issue focuses on interdisciplinary geosciences perspectives of tsunami that cover the whole process of tsunami disasters (generation, propagation, impact assessment, psychological perspectives, and planning). This special issue collects tsunami research papers not only as lessons from the 2011 Great East Japan tsunami, but also from other areas in Japan (coastal defense structures, tsunami fires, economic loss assessment, and emergency planning) as well as other countries (morphological changes in Indonesia and building risk assessment in New Zealand. The order of the paper follows the tsunami disaster process and the connections between each paper show the interdisciplinary perspectives of tsunami research, which can also be used as a framework for other types of disaster research. [ABSTRACT FROM AUTHOR]

Slow Slip Events (SSEs) are episodic slip events that play a significant role in the moment budget along subduction megathrust. They share many similarities with regular earthquakes, and have been observed in major subduction regions like, for example, Cascadia, Japan, Mexico, New Zealand. They show striking regularity, suggesting that it might be possible to forecast their size and timing, but the prediction of their extension and exact timing is still yet to come. They certainly are a great natural system to study how friction works at scale of the order of hundreds or thousands of km, and their recurrence time being much shorter than that of regular earthquakes, they give us the possibility to study multiple cycles and test their predictability. Here we focus on the Cascadia region, where SSEs recur every about 1 or 2 years, depending on the latitude. We use a catalog containing dozens of SSEs derived from the study of GPS position time series during the time span ranging from 2007 to 2017. The data show a clear segmentation with a few major patches interacting with one another, a behavior that recalls that of a discrete body system. We use both classical embedding theory and Extreme Value Theory applied to the study of dynamical systems to show that, where the Signal to Noise Ratio is sufficiently high, a low-dimensional (< 5) non-linear chaotic system is more appropriate to describe the dynamics than a stochastic system. We calculate major properties of the strange attractor like its correlation and instantaneous dimension, its instantaneous extremal index and a possible range for the metric entropy of the system. This knowledge is important for the determination of the predictability of the system, since it is related to the rate at which two trajectories in the phase space diverge. We further validate our results with a fuzzy inference system model to check the predictability of the slip and slip rate. In conclusion, SSEs in Cascadia can be described as a deterministic, albeit chaotic, system rather than as a random process. As SSEs might be regarded as earthquakes in slow motion, regular earthquakes might be similarly chaotic and predictable. [ABSTRACT FROM AUTHOR]

On 14 November 2016, the Northern part of New Zealand's South Island was struck by the Mw7.8 Kaikōura earthquake, an event of unprecedented geometric complexity rupturing at least 21 segments of the contractional North Canterbury and of the Marlborough fault systems. Geological, geodetic, tsunami and seismic data reveal puzzling features as well as observational difficulties of the event leading to competing views on its key features, such as the role played by the Hikurangi subduction interface, the exact rupture sequence, and the higher than expected local tsunami. We present a dynamic rupture model of the 2016 Mw 7.8 Kaikōura earthquake to unravel the event's riddles in a physics-based manner and provide insights on the mechanical viability of competing hypotheses proposed to explain them. The event is modeled using the open-source software SeisSol (www.seissol.org), based on a arbitrary high-order accurate DERivative Discontinuous Galerkin method (ADER-DG). We verify our model with strong ground-motions, high rate GPS, long-period teleseismic and tsunami data. Our model reproduces key characteristics of the event and constraints puzzling features inferred from high-quality observations including a large gap separating surface rupture traces, the possibility of significant slip on the subduction interface, the non-rupture of the Hope fault, and slow apparent rupture speed. We show that a rupture cascade sequentially breaking the Papatea and Kekerengu faults is dynamically consistent with regional stress estimates and a crustal fault network geometry inferred from seismic and geodetic data. A coseismically triggered tsunami caused by the rare occurrence of an earthquake starting on-land and crossing to two faults off-shore matches local tide gauge data.We find, that such complex rupture cascade links the crustal fault system when operating at low apparent friction thanks to the combined effects of overpressurized fluids, low dynamic friction and stress concentrations induced by deep fault creep. Understanding the physical conditions that allow rupture cascades on complex fault systems advances our ability to quantify earthquake hazard, especially to evaluate the possibility of extreme events on real fault networks. [ABSTRACT FROM AUTHOR]

The author reflects on the New Zealand government's response to the February 2011 Christchurch earthquake. He compares the disaster to the 2011 Japanese tsunami, discussing how the wealth of each nation affected the severity of human casualties and buildings destroyed. The author is critical of the Recovery Authority, stating that it has the same powers as the Minister for Earthquake Recovery. The article suggests that the Authority should make rules to promote private sector growth.