Questions to Ministers 1. Hon PHIL GOFF to the Prime Minister: Is he satisfied that actions to address the Christchurch earthquake are an adequate response; if not, what are his areas of concern? 2. AMY ADAMS to the Minister of Finance: What reports has he received on the economic impact of the earthquake in Christchurch on 22 February 2011? 3. Hon CLAYTON COSGROVE to the Minister for Canterbury Earthquake Recovery: Is he satisfied with the level of support being offered to the people of Christchurch in the wake of the earthquake on 22 February 2011? 4. NICKY WAGNER to the Minister for Social Development and Employment: What is the Government doing to support Canterbury businesses and employees through the earthquake recovery? 5. Hon ANNETTE KING to the Minister for Social Development and Employment: Is she confident that the Ministry of Social Development has responded adequately to the Christchurch earthquake? 6. METIRIA TUREI to the Minister of Finance: Has he considered raising a temporary levy on income to help fund the rebuilding of Christchurch; if so, how much could it raise? 7. AARON GILMORE to the Minister for Tertiary Education: What work has been done to help the families of tertiary students and tertiary institutions affected by the 22 February 2011 earthquake in Christchurch? 8. Hon JIM ANDERTON to the Minister for Canterbury Earthquake Recovery: Will he ensure that Christchurch homeowners and businesses are able to access insurance cover from existing policies or new cover they require since the 22 February 2011 earthquake? 9. Hon JOHN BOSCAWEN to the Attorney-General: Has he asked the Māori Party to agree to amendments to the Marine and Coastal Area (Takutai Moana) Bill that would make it explicitly clear that customary title holders would not be able to charge individuals for accessing a beach, and require any negotiated settlements to be referred back to Parliament for validation; if so, what response did he receive? 10. Hon DAVID PARKER to the Attorney-General: Does the Government intend to proceed this week with its legislation to replace the existing Foreshore and Seabed Act 2004? 11. RAHUI KATENE to the Minister for Canterbury Earthquake Recovery: Did he agree with his spokesman's response to the situation for residents in Christchurch East following the earthquake of 22 February 2011, that, "It is apparent, given the scale out there, that there just wasn't sufficient hardware out there, loos and the like", and what urgent actions have been taken to give priority to communities in the eastern suburbs? 12. COLIN KING to the Minister of Civil Defence: Why was a state of national emergency declared on 23 February 2011?
1. Hon PHIL GOFF to the Prime Minister: Does he have confidence in his Minister of Finance? 2. CRAIG FOSS to the Minister of Finance: How much does the Government expect to spend over the next few years to help rebuild Christchurch in the aftermath of the two earthquakes? 3. Hon ANNETTE KING to the Minister for Social Development and Employment: Does she stand by her statement in regard to hardship assistance that "…I think it proves that the help is there when people need it,"; if so, why? 4. RAHUI KATENE to the Minister of Health: What action, if any, has been taken in light of the study Ethnicity and Management of Colon Cancer in New Zealand: Do Indigenous Patients Get a Worse Deal?, which concluded that Māori New Zealanders with colon cancer were less likely to receive adjuvant chemotherapy and experienced a lower quality of care compared with non-Māori patients? 5. CHRIS AUCHINVOLE to the Minister for the Environment: What steps is the Government taking to increase renewable electricity generation in light of reports that greenhouse gas emissions from this sector have increased by 120 percent, which is more than any other sector since 1990? 6. Hon CLAYTON COSGROVE to the Minister of Finance: Excluding the banks and non-bank financial institutions covered by the deposit guarantee scheme, are there any other companies that might be provided with a government guarantee while the Rt Hon John Key is Prime Minister? 7. JONATHAN YOUNG to the Acting Minister of Energy and Resources: What is Petrobras able to do under the permit granted to it in the Raukumara Basin? 8. DAVID CLENDON to the Acting Minister of Energy and Resources: What environmental protection provisions, if any, did the Government include in the permit granted to Petrobras to explore for oil and drill off the East Cape? 9. Hon TREVOR MALLARD to the Prime Minister: Does he have confidence in all Ministers involved in the Mediaworks frequency payment arrangement? 10. AARON GILMORE to the Minister of Revenue: What has Inland Revenue done to assist the people in Christchurch after the February earthquake? 11. GRANT ROBERTSON to the Minister responsible for Ministerial Services: Does he stand by his statements in relation to the purchase of 34 BMWs by Ministerial Services, including one with heated seats, that "Yeah I don't know what's in Dunedin" and "It's beyond me, it's not my car anyway"? 12. SHANE ARDERN to the Minister of Fisheries and Aquaculture: What has been the result of enforcement action taken by the Ministry of Fisheries under Operation Paid and Taskforce Webb?
The Porters Pass fault (PPF) is a prominent element of the Porters Pass-Amberley Fault Zone (PPAFZ) which forms a broad zone of active earth deformation ca 100 km long, 60-90 km west and north of Christchurch. For a distance of ca 40 km the PPF is defined by a series of discontinuous Holocene active traces between the Rakaia and Waimakariri Rivers. The amount of slip/event and the timing of paleoearthquakes are crucial components needed to estimate the earthquake potential of a fault. Movement was assumed to be, coseismic and was quantified by measuring displaced geomorphic features using either tape measure or surveying equipment. Clustering of offset data suggests that four to five earthquakes occurred on the PPF during the Holocene and these range between ca 5-7 m/event. Timing information was obtained from four trenches excavated across the fault and an auger adjacent to the fault. Organic samples from these sites were radiocarbon dated and used in conjunction with data from previous studies to identify the occurrence of at least four earthquakes at 8500 ± 200, 5300 ± 700, 2500 ± 200 and 1000 ± 100 years B.P. Evidence suggests that an additional event is also possible at 6200 ± 500 years B.P. The ~1000, 5300 and 6200 years B.P. paleoearthquakes were previously unrecognised, while the 500 year event previously inferred from rock-avalanche data has been discarded. The present data set produces recurrence intervals of ~2000-2500 years for the Holocene. The identification of only one Holocene PPF rupture to the west of Red Lakes indicates the presence of a segment boundary that prevents the propagation of rupture beyond this point. This is consistent with displacement data and results in slip rates of 0.5-0.7 mm/yr and 2.5-3.4 mm/yr to the west and east of Red Lakes respectively. It is possible that the nearby extensional Red Hill Fault influences PPF rupture propagation. The combination of geometric, slip rate and timing data has enabled the magnitude of prehistoric earthquakes on the PPF to be estimated. These magnitudes range from an average of between 6.9 for a fault rupture from Waimakariri River to Red Lakes, to a maximum of 7.4 that ruptures the entire length of the PPAFZ, including the full length of the PPF. These estimates are approximately consistent with previous magnitude estimates along the full length of the PPAFZ of between 7.0 and 7.5.
METIRIA TUREI to the Minister for the Environment: Ki Te Minita mō Te Taiao: Ka tukua e ngā paerewa e whakaarohia akehia nei mō te pai ake o te wai i roto i te pūhera Wai Mā, te kaha kē atu, te iti kē iho rānei o te uru atu o te tūkinotanga ki roto i ō tātou awa wai, e ngā mea whakakapi? Translation: Do the proposed standards for water quality in the Clean Water package allow more pollution or less to enter our waterways than the ones they will replace? BRETT HUDSON to the Minister of Finance: How much is the Government committing to spend on infrastructure over the next 4 years? ANDREW LITTLE to the Prime Minister: Given his predecessor told the Pike River families, “I’m here to give you absolute reassurance we’re committed to getting the boys out, and nothing’s going to change that”, when, if ever, will he be announcing the re-entry of the drift? STUART SMITH to the Minister of Transport: What announcements has he made recently regarding the Government’s commitment to reinstate key transport links following the Kaikōura earthquake? JACINDA ARDERN to the Minister for Children: When was she first notified that the Ministry for Vulnerable Children Oranga Tamariki, or its predecessor CYF, were placing children and younger persons in a hotel or motel for short-term care without a supervisor, and what was her first action, if any? MELISSA LEE to the Minister of Health: Can he confirm that 55,000 care and support workers will share in the $2 billion pay equity settlement announced on 18 April 2017? GRANT ROBERTSON to the Minister of Finance: Does he agree with the Dominion Post editorial that his Government has “singularly failed to answer the pressures of Auckland”; if not, why does he think they would write this? ANDREW BAYLY to the Minister for Building and Construction: How do the latest reports on the level of building activity in Auckland and nationwide for the month, quarter, and year compare with 2016? Rt Hon WINSTON PETERS to the Prime Minister: Does he stand by all his statements; if so, how? PHIL TWYFORD to the Minister of Transport: Why has the completion of the $2.4 billion Western Ring Route been delayed, and when can Aucklanders expect the new motorway to be open? EUGENIE SAGE to the Minister of Conservation: Is it Government policy to increase the logging of native forests on West Coast conservation land? Dr MEGAN WOODS to the Minister supporting Greater Christchurch Regeneration: Does she agree that the first homes in the East Frame will be completed 5 months ahead of schedule? Questions to Members CLARE CURRAN to the Chairperson of the Commerce Committee: Does she intend to call for further submissions on the petition of Dame Fiona Kidman before it is reported back to the House, in light of the recently released footage shot inside the drift of the Pike River mine?
The last seven years have seen southern New Zealand a ected by several large and damaging earthquakes: the moment magnitude (MW) 7.8 Dusky Sound earthquake on 15 July 2009, the MW 7.1 Dar eld (Canterbury) earthquake on 4 September 2010, and most notably the MW 6.2 Christchurch earthquake on 22 February 2011 and the protracted aftershock sequence. In this thesis, we address the postseismic displacement produced by these earthquakes using methods of satellite-based geodetic measurement, known as Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS), and computational modelling. We observe several ground displacement features in the Canterbury and Fiordland regions during three periods: 1) Following the Dusky Sound earthquake; 2) Following the Dar eld earthquake and prior to the Christchurch earthquake; and 3) Following the Christchurch earthquake until February 2015. The ground displacement associated with postseismic motion following the Dusky Sound earthquake has been measured by continuous and campaign GPS data acquired in August 2009, in conjunction with Di erential Interferometric Synthetic Aperture Radar (DInSAR) observations. We use an afterslip model, estimated by temporal inversion of geodetic data, with combined viscoelastic rebound model to account for the observed spatio-temporal patterns of displacement. The two postseismic processes together induce a signi cant displacement corresponding to principal extensional and contractual strain rates of the order of 10⁻⁷ and 10⁻⁸ yr⁻¹ respectively, across most of the southern South Island. We also analyse observed postseismic displacement following the Dusky Sound earthquake using a new inversion approach in order to describe afterslip in an elasticviscoelastic medium. We develop a mathematical framework, namely the "Iterative Decoupling of Afterslip and Viscoelastic rebound (IDAV)" method, with which to invert temporally dense and spatially sparse geodetic observations. We examine the IDAV method using both numerical and analytical simulations of Green's functions. For the post-Dar eld time interval, postseismic signals are measured within approximately one month of the mainshock. The dataset used for the post-Dar eld displacement spans the region surrounding previously unrecognised faults that ruptured during the mainshock. Poroelastic rebound in a multi-layered half-space and dilatancy recovery at shallow depths provide a satisfactory t with the observations. For the post-Christchurch interval, campaign GPS data acquired in February 2012 to February 2015 in four successive epochs and 66 TerraSAR-X (TSX) SAR acquisitions in descending orbits between March 2011 and May 2014 reveal approximately three years of postseismic displacement. We detect movement away from the satellite of ~ 3 mm/yr in Christchurch and a gradient of displacement of ~ 4 mm/yr across a lineament extending from the westernmost end of the Western Christchurch Fault towards the eastern end of the Greendale East Fault. The postseismic signals following the Christchurch earthquake are mainly accounted for by afterslip models on the subsurface lineament and nearby faults.
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.
Landslides are significant hazards, especially in seismically-active mountainous regions, where shaking amplified by steep topography can result in widespread landsliding. These landslides present not only an acute hazard, but a chronic hazard that can last years-to-decades after the initial earthquake, causing recurring impacts. The Mw 7.8 Kaikōura earthquake caused more than 20,000 landslides throughout North Canterbury and resulted in significant damage to nationally significant infrastructure in the coastal transport corridor (CTC), isolating Kaikōura from the rest of New Zealand. In the years following, ongoing landsliding triggered by intense rainfall exacerbated the impacts and slowed the recovery process. However, while there is significant research on co-seismic landslides and their initial impacts in New Zealand, little research has explored the evolution of co-seismic landslides and how this hazard changes over time. This research maps landslides annually between 2013 and 2021 to evaluate the changes in pre-earthquake, co-seismic and post-earthquake rates of landsliding to determine how landslide hazard has changed over this time. In particular, the research explores how the number, area, and spatial distribution of landslides has changed since the earthquake, and whether post-earthquake mitigation works have in any way affected the long-term landslide hazard. Mapping of landslides was undertaken using open-source, medium resolution Landsat-8 and Sentinel-2 satellite imagery, with landslides identified visually and mapped as single polygons that capture both the source zone and deposit. Three study areas with differing levels of post-earthquake mitigation are compared: (i) the northern CTC, where the majority of mitigation was in the form of active debris removal; (ii) the southern CTC, where mitigation was primarily via passive protection measures; and (iii) Mount Fyffe, which has had no mitigation works since the earthquake. The results show that despite similar initial impacts during the earthquake, the rate of recovery in terms of landslide rates varies substantially across the three study areas. In Mount Fyffe, the number and area of landslides could take 45 and 22 years from 2021 respectively to return to pre-earthquake levels at the current rate. Comparatively, in the CTC, it could take just 5 years and 3-4 years from 2021 respectively. Notably, the fastest recovery in terms of landslide rates in the CTC was primarily located directly along the transport network, whereas what little recovery did occur in Mount Fyffe appeared to follow no particular pattern. Importantly, recovery rates in the northern CTC were notably higher than in the southern CTC, despite greater co-seismic impacts in the former. Combined, these results suggest the active, debris removal mitigation undertaken in the northern CTC may have had the effect of dramatically reducing the time for landslide rates to return to pre-earthquake levels. The role of slope angle and slope aspect were explored to evaluate if these observations could be driven by local differences in topography. The Mount Fyffe study area has higher slope angles than the CTC as a whole and landslides predominantly occurred on slightly steeper slopes than in the CTC. This may have contributed to the longer recovery times for landsliding in Mount Fyffe due to greater gravitational instability, however the observed variations are minor compared to the differences in recovery rates. In terms of slope aspect, landslides in Mount Fyffe preferentially occurred on north- and south-facing slopes whereas landslides in the CTC preferred the east- and south-facing slopes. The potential role of these differences in landslide recovery remains unclear but may be related to the propagation direction of the earthquake and the tracking direction of post-earthquake ex-tropical cyclones. Finally, landslides in the CTC are observed to be moving further away from the transport network and the number of landslides impacting the CTC decreased significantly since the earthquake. Nevertheless, the potential for further landslide reactivation remains. Therefore, despite the recovery in the CTC, it is clear that there is still risk of the transport network being impacted by further landsliding, at least for the next 3-5 yrs.
Sea level rise is one consequence of Earth’s changing climate. Century-long tide gauge records show that global-mean sea-level rise reached 11-16 cm during the twentieth century at a mean rate of 1.2 mm/y. Today, the average rate of global-mean sea-level rise is higher at 3-4 mm/y and is expected to increase in the future. This represents a hazard to low elevation coastal zones worldwide. Yet, before global sea level projections can be used to characterise future coastal flood hazard at a local scale, the effects of tectonics (and other processes) that drive vertical land motion (VLM) must be considered. VLM is defined as the vertical velocity (uplift or subsidence) of the solid surface with respect to the centre of Earth. In this study, new VLM maps are generated over coastal strips in New Zealand, using Sentinel-1 InSAR and GNSS data. In New Zealand, measuring VLM using InSAR on naturally vegetated or agricultural land is difficult due to signal decorrelation. Along the rural Bay of Plenty coastal strip, I use a persistent-scatterer approach to generate a VLM map from both east-looking ascending and west-looking descending Sentinel-1 data between 2015-2021. Using time-series data over the same time period from a dense network of 20 GNSS sensors, I tie InSAR-derived line-of-sight velocity to the 2014 ITRF reference frame. I test two different methods for measuring VLM and compare the results against GNSS vertical velocity along the Bay of Plenty coast. Best results are achieved by first removing the interpolated horizontal GNSS velocity field from each of the InSAR datasets, before averaging the two VLM estimates. Measured VLM is between -3 and 3 mm/y, with negative values (subsidence) occurring within the low-lying Rangitāiki Plain and Ōpōtiki valley, and uplift across the elevated region west of Matatā. This thesis integrates geomorphological, geological, and historical levelling VLM records with modern satellite datasets to assess VLM across timescales ranging from 10 to 100,000 years at Matatā. Uplift rate has been variable through time, with average uplift over the last 300,000 years of 1 mm/y, 4.5 mm/y since 1720 years, 2 mm/y between 1950-1978, and 10 mm/y between 2004-2011. Previous modelling has shown that the best fit to the 2004-2011 rapid uplift rates is an inflating magmatic source at ~10 km depth beneath Matatā. To reconcile all data, I present a VLM model that consists of short-lived periods (7 years) of rapid uplift (10 mm/y), separated by longer periods (30 years) of lower background uplift (3 mm/y). The episodic nature of VLM at Matatā likely reflects short-lived periods of magmatic intrusion. Episodic VLM characterised by large rates of uplift (10 mm/y) has been seen at Taupō volcano, and other volcanic centers globally. It has been 12 years since the end of the last intrusion episode; this modelling suggest one may expect to observe increased uplift rates at Matatā in the coming decades. Densely populated urban coastal strips are most at risk from the effects of relative sea-level rise. At the same time, anthropogenic activities associated with urbanization, such as groundwater withdrawal, and land reclamation can lead to local land subsidence (LLS), further exacerbating the risk to urban infrastructure. LLS refers to subsidence relative to nearby land area assumed to be stable. In this thesis, I create the first high-resolution (10 m) maps of LLS at six urban coastal strips in New Zealand, with a combined length of 285 km, using Sentinel-1 InSAR data between 2018-2021. This analysis reveals 89% of urban coastal strips are subsiding at rates of -0.5 mm/y or greater, and 11% is subsiding at higher rates of -3.0 mm/y or greater. On average, subsidence is -0.6 to -2.9 mm/y higher at the coastal strip, compared to inland areas occupied by GNSS stations. This analysis also documents highly-localised hotspots of LLS, with subsidence rates of up to -15 mm/y. In Christchurch, rapid and localised subsidence (-8 mm/y) is observed within coastal suburbs New Brighton and Southshore. In most cities, the highest subsidence rates occur on land reclaimed in the early-late twentieth century, and in areas built on Holocene sediment. Time-series analysis of LLS at sites of reclaimed land shows both linear and non-linear rates of deformation over time periods of up to 6-8 years. This thesis highlights the variable exposure to relative sea-level rise of New Zealand coastal strips, and demonstrates that in many cases current rates of VLM should be expected to continue for the next few decades.