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The magnitude 7.8 earthquake that struck North Canterbury, on the east coast of New Zealand's South Island on 14 November 2016 had significant impacts and implications for the community of Kaikōura and surrounding settlements. The magnitude and scope of this event has resulted in extensive and ongoing geological and geophysical research into the event. The current paper complements this research by providing a review of existing social science research and offering new analysis of the impact of the earthquake and its aftermath on community resilience in Kaikōura over the past five years. Results demonstrate the significant economic implications for tourism, and primary industries. Recovery has been slow, and largely dependent on restoring transportation networks, which helped catalyse cooperation among local hospitality providers. Challenges remain, however, and not all sectors or households have benefited equally from post-quake opportunities, and long-term recovery trajectories continue to be hampered by COVID-19 pandemic. The multiple ongoing and future stressors faced by Kaikōura require integrated and equitable approaches in order to build capability and capacity for locally based development pathways to ensure long-term community resilience. [ABSTRACT FROM AUTHOR]

This is the first of a two-part New Zealand Journal of Geology and Geophysics Special Issue that focuses on improving our understanding of sedimentary systems of the Hikurangi Subduction Margin, Aotearoa-New Zealand. It is amongst the world's youngest and most accessible active subduction margins and its sedimentary basins preserve a rich history of inception and ongoing evolution, spanning trench to back-arc positions. These sediments and sedimentary rocks provide a record of surface processes from the latest Paleogene to today, and reflect the spatio-temporal variability of the effects of subduction, seismicity, volcanism, evolving sediment sources, routing systems and processes, all imprinted upon by glacio-eustatic sea-level changes. The papers in this volume focus on the interplay between controlling mechanisms and the dynamics of these systems, from both onshore and offshore sedimentary environments. This issue is divided into two themes, distinguished by geological age: 1. Miocene Sedimentary Systems and intra-slope basin evolution, and 2. Insights from Quaternary Sedimentary Systems from the trench to the inner margin. Collectively, these papers represent significant advances into our understanding of sedimentary systems within the Hikurangi Subduction Margin, with innovative results that may find applications to other convergent settings. [ABSTRACT FROM AUTHOR]

Launched in 2015, the New Zealand volcano supersite provides regular radar acquisitions covering all the major calderas and cone volcanoes which form the Taupō Volcanic Zone (TVZ). This paper documents new InSAR (Interferometric Synthetic Aperture Radar) observation of deformation over the cone volcanoes within the TVZ including the Tongariro Volcanic complex (TVC) and White Island. Observations over White Island support earlier observations indicating that the stability of the crater wall is controlled, at least in part, by the water level in the crater lake with downslope motion of ∼50 mm/yr observed during the latest period of lake drop in early 2019. Deformation over the TVC is dominated by the continued subsidence above the 2012 Te Maari eruption site at rates of ∼30 mm/yr with no evidence of deformation elsewhere. Synthetic models, used to test the potential detectability of magma movement beneath Ruapehu and White Island, suggest that for small volumes (<0.005–0.02 km3), intruded over short periods of time, it would be difficult for InSAR data alone to identify their accumulation. These challenges are not unique to New Zealand's volcanoes and are likely to be faced at other volcanic systems globally. [ABSTRACT FROM AUTHOR]

Numerous igneous bodies within the Deepwater Taranaki Basin are recognised mainly from seismic data and range from Early Cretaceous to Pliocene in age. They were all emplaced within an intra-plate setting but are scattered apparently at random in time and space. This paper describes the occurrences of igneous rocks within the basin as interpreted from seismic data, and discusses their possible origin. There are no indications of hotspot tracks within the Zealandia micro-continent so an alternative origin is sought. Previous authors see the main cause of volcanism as decompression melting due to localised lithospheric detachment and the movement of the Zealandia plate across the mantle as incidental. It is suggested that the movement of the Zealandia lithosphere, in the order of 4000 km to the north-northwest since the Cretaceous, may have caused drag across the asthenosphere, which in turn created transient small-scale convection cells that assisted the process of decompression melting as a modification to the accepted theory. [ABSTRACT FROM AUTHOR]

This paper presents a generalised velocity model construction methodology, its computational implementation, and application in the construction of a New Zealand Velocity Model (NZVM2.0) for use in physics-based broadband ground motion simulation. The methodology utilises multiple datasets spanning different length scales, which is enabled via the use of modular subregions, geologic surfaces, and parametric representations of crustal velocity. A number of efficiency-related workflows to decrease the overall computational construction time are employed, while maintaining the flexibility and extensibility to incorporate additional datasets and refined velocity parameterisations as they become available. The methodology and computational implementation processes are then applied for development of a New Zealand Velocity Model (NZVM2.0) for use in broadband ground motion simulation. The model comprises explicit representations of the Canterbury, Wellington, Nelson-Tasman, Kaikōura, Marlborough, Waiau, Hanmer and Cheviot sedimentary basins embedded within an existing regional travel-time tomography-based velocity model for the shallow crust. [ABSTRACT FROM AUTHOR]

This paper provides new maps of the surficial sediment distribution on the continental shelf (0∼150 m water depth) of New Zealand based on a new database - nzSEABED. The maps of percent mud, sand, gravel and carbonate, are compared with previous research to provide a comprehensive update of the surficial sediment distributions on the continental shelf, together with a review of the main environmental (oceanographic and climatic), geomorphological and geological processes and human activities that have influenced sediment deposition. Continental shelves are dynamic regions that are in a constant state of flux from floods, storms, tides, waves, earthquakes and volcanic activity. While some of these events may be captured by individual samples, the compilation of >23,000 samples collected and analysed over 60 years provides a long-term average distribution of sediments on the continental shelf that can inform future research and coastal management. [ABSTRACT FROM AUTHOR]

For many decades, there has been speculation about when the Alpine Fault first became a major regional structure. This paper presents a summary of recently published data, especially U-Pb ages, that supports the existence of a Late Cretaceous to Paleogene proto-Alpine Fault in the form of a thermotectonic corridor between North and South Zealandia. The evidence takes the form of fault-controlled sedimentary basins, ductile shear zones, Alpine Schist regional metamorphism and igneous rocks. Much critical evidence has been removed or strongly modified by Neogene shortening and the total lateral displacement history of the proto-Alpine Fault cannot yet be unambiguously determined. [ABSTRACT FROM AUTHOR]

New Zealand has a network of approximately 190 Continuously Operating Reference Stations (CORS) operated by GeoNet, is a project housed within GNS Science. The GeoNet continuous GNSS network (cGNSS) includes the 37 stations that make up the Land Information New Zealand (LINZ) PositioNZ network. These stations are run in partnership by the two agencies. The New Zealand CORS stations make a significant contribution to New Zealand's geospatial infrastructure and to international geodesy. Further, the CORS stations have been used to identify more than 25 slow-slip events (SSEs) associated with the Hikurangi subduction zone, play an important role in volcano monitoring and have the potential to identify tsunamigenic earthquakes. This paper will discuss how the two networks were established, how they have evolved since the first stations were established in 1995 and the significant contribution of the late John Beavan. [ABSTRACT FROM PUBLISHER]

The Repongaere Fault is one of a series of active normal faults within the Raukumara Peninsula, eastern North island, New Zealand. These faults appear to form in response to rapid uplift of the Raukumara Range and related extensional strain. however, the activity of these normal faults is poorly constrained. This paper presents new mapping of the active surface trace of the Repongaere Fault, c. 18 km northwest of Gisborne, and the results of two paleoseismic trenches. These results are then used to assess the seismic hazard posed by this fault and impacts on the Waipaoa Sedimentary System in which the fault is situated. active traces can be mapped for c. 4.5 km, but we infer the surface rupture length to be at least 9 km. Tephras within the trenches constrain the timing of the most recent surface rupture event to have occurred during deposition of the Waimihia Tephra (c. 3400 cal. yr BP), and at least one event in the period c. 13 800-5470 cal. yr BP, with single-event displacements of ≥ 0.4-1.1 m. From these data a mean dip-slip rate of c. 0.1 mm/yr and a maximum recurrence interval of 4490-6900 yr, can be calculated. if the Repongaere Fault is representative of other Raukumara Peninsula normal faults, then this relatively low rate of activity supports the interpretation that these faults are not contributing significantly to the deformation of the Raukumara Peninsula. The low rate of activity is also consistent with the very localised evidence for landscape impacts, a calculated moderate Mw of 6.3-6.7, and the fault's location within the lower part of the Waipaoa River catchment. Together, these observations suggest that Repongaere Fault earthquakes have minimal, localised impact on the Waipaoa Sedimentary System. [ABSTRACT FROM AUTHOR]