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Our ability to address many key questions regarding physical oceanography, plate boundary processes and marine biodiversity, and to undertake geohazards monitoring in the New Zealand region, is greatly hampered by the lack of access to real-time, continuous offshore monitoring of a range of key observables beneath our oceans, which comprises >95% of our Exclusive Economic Zone (EEZ). Developing the ability to monitor geological, biological and oceanographic processes within our EEZ is required to better understand the hazard and risk posed to New Zealand’s citizens and our economy by our offshore tectonic plate boundaries and the impact of future climate change on fisheries, weather, marine biodiversity and ocean circulation. To discuss the possibilities for future permanent offshore monitoring, a two-day workshop on ‘Scientific and monitoring priorities for cabled infrastructure offshore New Zealand’ was held at GNS Science in Lower Hutt, New Zealand, on 23–24 February 2021. The workshop brought together the New Zealand Geoscience and Ocean Science communities, international experts and other interested stakeholders to discuss the scientific and geohazards monitoring benefits of instrumented fibre-optic cables offshore of New Zealand. Excellent presentations from both international and New Zealand invited speakers achieved the important goal of laying the framework for the current technological capabilities in offshore cabled monitoring and set the stage for discussion of the key scientific questions that can be addressed in New Zealand with such infrastructure (see Appendix 1 for workshop schedule). More than 75 participants from more than 25 institutions in eight different countries attended the workshop (see Appendix 2 for participant list). Approximately 40 participants attended in person, while other attendees (particularly those from overseas) joined the workshop online. The discussion addressed ways of leveraging the opportunities presented by a proposed fibre-optic telecommunications cable extending ~800 km from the east coast of the New Zealand mainland to the Chatham Islands. Presentations were also made by international experts on developments in seafloor monitoring technologies and offshore cabled networks, promoting extensive discussion of their advantages and disadvantages. The primary scientific questions and geohazard monitoring priorities that would benefit from permanent, offshore instrumentation were discussed, as well as hazards that could be faced by a cable transecting alternative routes. This report summarises the main findings and conclusions of the workshop and background information necessary for considering the development of permanent offshore observing capability in New Zealand. We present the pros and cons of potential routes for a cable to the Chatham Islands from a scientific and technical perspective. A primary conclusion of the workshop, and a recommendation of this report, is that a hybrid cable design incorporating both ‘in-line’ sensors and external sensors connected to branching units, plus fibre strands usable for distributed acoustic sensing (DAS), would provide the best balance between the oceanographic, geophysical and geohazards monitoring benefits of offshore scientific infrastructure. This approach to the cable design would future-proof the cable and its sensor payloads, maximising the return on investment as technology improves in decades to come, while ensuring that the scientific components did not compromise the cable’s primary telecommunications mission. Many of the scientific sensing capabilities that we discuss would also enable more comprehensive monitoring of cable health and potential risks posed to the cable. Incorporating branching units to which external instrument packages can be attached would ensure that instruments can be replaced and new sensors added as technology improves. Incorporating additional dark fibres (for DAS and related applications) would enable New Zealand to take full advantage of rapidly evolving capabilities in this frontier technique at modest additional cost. SMART instrumentation installed at repeater nodes would provide long deep-ocean temperature time series, as well as seafloor pressure and seismological sensing capability that can contribute to tsunami and earthquake early warning capabilities and provide proof-of-concept for similar projects elsewhere in the southwest Pacific region. Further discussion and research will be required among smaller working groups to finalise an optimal design for integrating science capability into a telecommunications cable that maximises scientific and monitoring benefits of such a cable in the New Zealand context. Different cable routes would offer different opportunities and pose different challenges. In light of the workshop discussions, this report identifies a route option extending south from Gisborne for ~150 km (paralleling the east coast) before turning southeastward to the Chatham Islands as providing the greatest benefit for scientific (geophysical and oceanographic aims) and geohazard monitoring purposes. The incorporation of scientific sensor payloads in a cable extending to the Chatham Islands would offer a unique opportunity for New Zealand to lead the way in establishing critical multi-disciplinary offshore observing capability by leveraging telecommunications infrastructure and investment. (auth)

Transitioning to a net-zero-emission future will require a transformation of New Zealand’s economy and society. The costs of meeting the Government’s emissions reduction targets could be large, and new technologies will be required. In coming decades, petroleum products will continue to play an important role in society, both for transportation and petrochemicals (and potentially some industrial heat applications). The dilemma we face is that our current petroleum and natural gas resources will only last for around another decade at current rates of extraction, new exploration opportunities are limited and global competition for the labour and capital to develop new resources is fierce. Without a continued supply of natural gas and other petroleum products, New Zealand may not be able to engineer and afford the transition to a net-zero carbon economy. A workshop was held in Dunedin on the 7th August 2019 to explore the role that a hypothetical, large gas discovery offshore of Te Waipounamu / South Island would have on the transition to a low-emissions economy. The goal was to provide a clearer understanding around where the experts agree, and where there is a need for more research and debate. The small-group session was based around decision trees and timelines. It identified a series of conditions whereby future natural gas development in New Zealand would be more likely to receive social licence and be publicly acceptable. These include: feasible and cost-effective carbon dioxide capture and storage; production of New Zealand natural gas reserves that would reduce overall global emissions by offsetting coal (that produces more CO2 per unit of useful energy), both internationally and locally; sufficient demand for natural gas, both internationally and locally; an economically feasible domestic distribution network (presently only on the North Island) adaptability of utilising natural gas infrastructure for hydrogen in the future; opportunities for the government to influence development through contracts and licenses; effective management of local environmental risks; social license to produce and consume, or to export, natural gas after 2030; and decision-making processes consistent with the principles of Te Tiriti o Waitangi. (auth)

As part of a wider study of the public perception of the petroleum resource sector in New Zealand, the relationship between Māori and the oil and gas industry has been reviewed in the context of cultural, economic and societal factors. Existing literature on the subject can be divided into several themes, including submissions to and reports from the Waitangi Tribunal, books and articles on the early history of the petroleum industry in New Zealand, guides to engagement with Māori in resource development and magazine articles describing individual community responses to modern oil and gas activity. The Treaty claims and the resulting reports highlight that Māori are fundamentally concerned with the loss of access to the resources from the onset of land confiscation. The loss of access to petroleum resources is viewed as a fundamental breach of the Treaty of Waitangi, for which compensation should be given. However, the economic loss is only part of the issue, and wider themes of the lack of stewardship over the resources, and the environmental and cultural damage done by exploration and exploitation, continue to be key factors in the Māori response to the sector. A review of the historical changes to Māori engagement with the oil and gas industry shows that local and international politics are also closely tied to the approaches of iwi and hapū to protect the resource. Over the last 150 years, global issues such as wars, energy crises, climate change and legislation and societal change in New Zealand have influenced attitudes to oil and gas. There are a wide range of positions taken by Māori groups that continue to grapple with the complex issues around guardianship of the natural resource and the opportunities for economic benefits for their people. While most modern exploration companies are undertaking significant engagement with Māori communities, there is insufficient recognition of the risks to the disruption of the Māori world by exploration and production activities. (auth)

In March 2019, GNS Science and Ngāti Tama, in collaboration with Ngāti Mutunga, led a Te Kura Whenua wānanga at Pukearuhe Marae, Urenui, Taranaki. Te Kura Whenua is a community engagement initiative aimed at creating dialogue and sharing knowledge between scientists and Māori communities on geoscience-related topics, such as climate change, geological hazards and geological resources, and Māori perspectives on the whenua. The two-and-a-half day wānanga involved field-based and hands-on activity-based learning. This report outlines these activities and summarises the outcomes of the wānanga. A total of 12 participants and 8 facilitators attended the wānanga. Participants ranged in age and backgrounds. The experiential learning format of the wānanga appealed to the participants who gained a ‘western science’ view on geoscience-related topics and gave positive feedback on their experiences. The facilitators gained a better understanding of iwi perspectives on whakapapa, environmental protection and natural resources. The wānanga at Pukearuhe Marae adds to the successful line of iwi-focused GNS Science engagement initiatives under the Te Kura Whenua banner. (auth)

The Alpine Fault zone in New Zealand marks a major transpressional plate boundary that is late in its typical earthquake cycle. Understanding the subsurface structures is crucial to understand the tectonic processes taking place. A unique seismic survey including 2D lines, a 3D array, and borehole recordings, has been performed in the Whataroa Valley and provides new insights into the Alpine Fault zone down to ∼2 km depth at the location of the Deep Fault Drilling Project (DFDP)‐2 drill site. Seismic images are obtained by focusing prestack depth migration approaches. Despite the challenging conditions for seismic imaging within a sediment filled glacial valley and steeply dipping valley flanks, several structures related to the valley itself as well as the tectonic fault system are imaged. A set of several reflectors dipping 40°–56° to the southeast are identified in a ∼600 m wide zone that is interpreted to be the minimum extent of the damage zone. Different approaches image one distinct reflector dipping at ∼40°, which is interpreted to be the main Alpine Fault reflector located only ∼100 m beneath the maximum drilled depth of the DFDP‐2B borehole. At shallower depths (z, Plain Language Summary: The Alpine Fault in New Zealand is a major plate boundary, where a large earthquake will likely occur in the near future. Thus, it is important to understanding the detailed processes of how and where such an earthquake occurs. Many scientists are involved in this work, particularly in the attempt of drilling through the fault zone with a ∼900 m deep borehole. We analyzed new seismic data from this area using sensors in the borehole and at the surface to record small ground movements caused by a vibrating surface source causing waves that travel through the ground. From these data, we obtained a detailed image of the structures in the subsurface, for the first time in 3D, by applying advanced analysis methods. Hence, we can better understand the shape of the glacial valley and of the fault zone, that is, the local structures of the continental plate boundary. We interpret at least 600 m wide zone of disturbed rocks and identify a potential major fractured plane down to about 1 km depth. Our studies may help to understand structures that host earthquakes in this area., Key Points: We use focusing prestack depth migration with detailed seismic data to analyze the complex subsurface environment of the Alpine Fault zone. Seismic images show Alpine Fault zone related reflectors at a depth of ∼0.2–1 km dipping ∼40°–56° around the DFDP‐2B borehole. Complex structures within the glacial Whataroa Valley are imaged showing steep valley flanks, faults, and internal sedimentary horizons., German Research Foundation (DFG), Earthquake Commission (EQC) http://dx.doi.org/10.13039/100012181, NSERC discovery and Canada Research Chairs Program, Canadian Foundation for Innovation