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Sub‐seabed fluid flow, gas hydrate accumulation and seafloor methane seepage are tightly interwoven processes with implications for marine biodiversity, ocean chemistry and seafloor stability. We combine long‐offset seismic reflection data with high‐resolution seismic data to investigate shallow structural deformation and its relationship to focused gas migration and hydrate accumulation in the southern Hikurangi subduction wedge. Anticlines, effective traps for focusing free gas, are characterized by both normal faults and vertical zones of hydraulic fracturing within the hydrate stability zone. The normal faults form as a result of sediment layer folding and gravitational collapse of ridges during uplift. We document both longitudinal (ridge‐parallel) and transverse (ridge‐perpendicular) extensional structures (normal faults and elongated hydraulic fracture zones) in the sub‐seafloor of anticlinal ridges. Intriguingly, gas flow through ridges close to the deformation front of the wedge exploits longitudinal structures, while ridges further inboard are characterized by gas flow along transverse structures. This highlights pronounced changes in the shallow deformation of ridges in different parts of the wedge, associated with a switching of the least and intermediate principal stress directions. It is critical to understand these shallow stress fields because they control fluid flow patterns and methane seepage out of the seafloor. Plain Language Summary: Methane gas is released naturally from the seafloor at locations known as "gas seeps." Gas seeps often occur on seafloor ridges, because gas tends to flow into folded sediments beneath ridges. In this study, we explored how geological structures (faults and fractures) beneath seafloor ridges control the flow of gas toward the seafloor. We observed that gas flow beneath ridges is aligned along one of two main orientations: either approximately parallel or perpendicular to the long‐axis of the ridge. Structures aligned parallel with a ridge axis occur beneath ridges near the toe of the accretionary wedge—that is, at the seaward end of the large wedge of deformed sediments that has formed as a result of one tectonic plate sliding beneath another. Structures aligned perpendicular to the ridge occur further landward within the accretionary wedge. The change in the orientation of structures was unexpected, and shows us there are significant differences in the way ridges deform as they develop through geological time. The results are important because geological structures control how and where gas migrates to the seafloor, where it then acts as a food source for diverse biological communities, while also influencing the chemistry of the ocean. Key Points: Gas migration through ridges occurs along both longitudinal (ridge‐parallel) and transverse (ridge‐perpendicular) zones of fracturingShallow stress fields differ significantly between ridges, reflecting differences in ridge evolution and deformationSeismic reflection images of the base of gas hydrate stability and gas‐water contacts are strongly affected by seismic frequency content [ABSTRACT FROM AUTHOR]

This paper is devoted to the brilliant Czech logician and philosopher of language Pavel Tichý (1936-1994) who, after emigrating to New Zealand in 1970 and spending half his life there as a political refugee, committed suicide shortly before returning to his alma mater, Charles University in Prague, as Chair of the Department of Logic in the Faculty of Arts. After tracing a biographical profile of the Czech logician, the paper explains some of the central ideas of Tichý's highly original theory, called Transparent Intensional Logic, while locating it in the wider context of the analytic philosophy of language. The paper concludes by highlighting the role played by Tichý's intensional theory in advancing various disciplines, including artificial intelligence, with the aim of shedding light on the significant contributions of the Czech logician, who has yet to gain due recognition. [ABSTRACT FROM AUTHOR]

The complexity of farming and rural communities poses challenges to research and extension initiatives seeking industry-wide change. The effectiveness of these initiatives depends on factors ranging from individual psychology to the science of effects. Tools like intervention logic models, which visualise the causal chain of an intervention through to its impact, are useful for programme planning but are of limited usefulness for comparing the relative benefits of initiatives. Benefit-cost analysis can quantify relative benefits, but applications often oversimplify the causal chain and leave key impacts unquantified. This paper aims to develop a benefit-cost analysis modelling framework that both captures the important causal logic from intervention to impact as well as quantifying and monetising key benefit categories. We apply the framework to value the impacts of 'Hill Country Futures', a programme of research and extension designed to assist in future-proofing the environmental sustainability, profitability, and well-being of New Zealand's hill country farmers, their farm systems, and communities. The QUICK (Quantifying and Understanding the Impact of Capability and Knowledge) model uses an agent-based simulation to represent processes of skill development and practice improvement that result from both extension activities for management and research tools as well as the use of those tools. We calibrate the model using a combination of an external predictive adoption model, an expert workshop, and researcher judgment. We use a choice experiment to value simulated changes in financial, environmental, community, and well-being outcomes. We explore how optimising the programme of extension interventions through targeting could increase impact. Our results suggest that the benefits of the 'Hill Country Futures' programme outweigh the costs by a factor of 13.5. We find that targeting extension efforts towards building awareness could be slightly more beneficial than targeting both awareness and skill development. We find no evidence that targeting extension efforts towards the best resource would be beneficial. This paper combines desirable features from intervention logic models, benefit-cost analysis, choice modelling, and agent-based models to value the benefits of a large programme of research and extension. It highlights that such modelling can be useful for evaluating both planned and complete programmes. [Display omitted] • Programme evaluation is dominated by qualitative research and would often benefit from more quantitative analysis. • We evaluate Hill Country Futures, designed to improve the sustainability and profitability of hill country farmers. • We combine intervention logic models with benefit-cost analysis using an agent-based approach informed by choice modelling. • Our results suggest that the programme will deliver substantial benefits compared to costs, with a benefit-cost ratio of 13.5. • We show the potential of using intervention logic with benefit-cost analysis to value agricultural research and extension. [ABSTRACT FROM AUTHOR]

Although the link between agriculture and diffuse water pollution has been understood for decades, there is still a need to implement effective measures to address this issue. In countries with light-touch regulation, such as New Zealand and Australia, most efforts to promote environmental management practices have relied on voluntary initiatives such as participatory research and extension programmes; the success of which is largely dependent on farmers' willingness and ability to adopt these practices. Increased understanding of the factors influencing farmer decision-making in this area would aid the promotion of effective advisory services. This study provides insights from 52 qualitative interviews with farmers and from observations of nine farmer meetings and field days. We qualitatively identify factors that influence farmer decision-making regarding the voluntary uptake of water quality practices and develop a typology for categorising farmers according to the factors that influence their decision-making. We find that in light-touch regulated countries certainty around policy and also around the effectiveness of practices is essential, particularly for farmers who delay action until compelled to act due to succession or regulation. The contribution of this paper is threefold: (i) it identifies factors influencing decision-making around the uptake of water quality practices in a light-touch regulated country; (ii) it develops a typology of different farmer types; and (iii) it provides recommendations on policy approaches for countries with light-touch regulation, which has potential relevance for any countries facing changes regarding their agricultural policy, such as post-Brexit policy in the UK. [ABSTRACT FROM AUTHOR]

A group-based reproductive management extension programme has been designed to help managers of dairy herds improve herd reproductive performance. The aims of this study were, firstly, to assess effects of participation by key decision makers (KDMs) in a farmer action group programme in 2009 and 2010 on six key management outcomes (KMOs) that affect reproductive performance over 2 years (20092010 and 2010-2011), and secondly, to describe KDM intentions to change management behaviour(s) affecting each management outcome after participation in the programme. Seasonal calving dairy herds from four regions of New Zealand were enrolled in the study. Intentions to modify management behaviour were recorded using the formal written action plans developed during the extension programme. KMOs assessed were calving pattern of the herd, pre-calving heifer liveweight, pre-calving and premating body condition score (BCS), oestrus detection, anoestrus cow management and bull management. Participation was associated with improvements in heifer liveweight, more heifers calving in the first 6 weeks of the seasonal calving period, premating BCS and oestrus detection. No significant effects were observed on anoestrus cow management or bull management. KDMs with greater numbers of proposed actions had lower 6 week in-calf rates in the second study year than KDMs who proposed fewer actions. A more effective strategy to ensure more appropriate objectives is proposed. Strategies to help KDMs to implement proposed actions more successfully should be investigated to improve the programme further. [ABSTRACT FROM AUTHOR]

Abstract: The marine magnetic anomaly record and plate kinematics derived from that data provide evidence of numerous cases of significant changes in plate motions and plate interactions. However, in most cases the temporal resolution provided by the marine record does not discriminate between punctuated (abrupt) or smooth variations in plate motions. During a 10million year period (~30Ma to 20Ma), the Euler poles (stage poles) describing Australia–Pacific relative plate motion migrated more than 20° in latitude. The New Zealand segment of the plate boundary is close to the location of the Euler poles and their migration making the tectonics of its plate boundary structures particularly sensitive to the history of plate kinematics. Based on the rapid southward migration of the Euler (stage) poles from north of New Zealand to south of the landmass, there is an expected rapid, migrating transition from an extensional (stage pole north of the site) to transpressional (stage pole south of the site) plate boundary system. The geologic signature of this rapid change in plate boundary kinematics is preserved in the stratigraphic record of a suite of basin deposits that span the latitudinal sweep of the migrating Euler poles. Analyses of these deposits indicate that the timing of the transition from extensional to transpressional tectonics shows a continuous and systematic southward sweep, indicating that the changes in Australia–Pacific plate motions during the 30Ma–20Ma interval were smoothly continuous and not punctuated. [Copyright &y& Elsevier]

The Horse Range Formation is a structurally controlled late early cretaceous to early late cretaceous nonmarine unit in east Otago, South island, New Zealand, containing immature lithic debris. clasts are generally rounded, with only minor subangular material. The formation contains clasts derived from two principal basement sources: schist and greywacke. Schist debris is most abundant at the base of the described section, and this material is dominated (>60%) by quartz from the greenschist facies core of the Otago Schist belt. conglomerates with >70% greywacke clasts constitute most of the upper part of the Horse Range Formation. These greywacke conglomerates have a matrix of sand derived mainly from schist. a 60 m thick wedge of quartz-rich, locally carbonaceous sand occurs interlayered with greywacke conglomerates. The Horse Range Formation rests on sub-greenschist facies semischist, which forms only a small proportion (<10%) of conglomerate clasts, and most sediment underwent considerable transport (tens of kilometres). Paleocurrent indicators suggest that sediment was derived mainly from the northwest, and drainage was probably controlled by the ongoing development of the northwest-striking waihemo Fault System, which had normal sense of motion at that time. The formation is developed from the remnants of a braided axial river flowing southwest from active uplift of greywacke ridges along the waihemo Fault System at least 50 km inland. Some lateral input occurred from the adjacent schist belt that was being exhumed by the extensional tectonics. Post-depositional diagenesis of the sediments has resulted in widespread replacement of silicate minerals, particularly albite, by calcite that forms up to 40% of the rock locally. The calcite has δ18OSMOW near +24‰ and δ13cPDBPDB near -2‰, and was partly dissolved and redeposited from the immature basement debris (metamorphic calcite) and partly introduced from overlying late cretaceous and Teriary marine sediments by groundwater. [ABSTRACT FROM AUTHOR]

A set of more than 50 mineralised normal faults cuts lower greenschist facies rocks at the northeastern margin of the Otago Schist belt near Oturehua, central Otago. The faults strike northwest and dip steeply (>60°) northeast, and individual mineralised zones are traceable for up to 700 m along strike. The mineralised faults are closely associated with, and are generally parallel to, a swarm of northwest striking, steeply dipping extensional quartz ± ankerite veins (centimetre scale) that occur over an area of at least 25 km² in the host schist. Mineralised faults contain 10-100 cm thick quartz veins that are traceable as interlinked structures for tens of metres along strike. Where faults cut massive quartz-feldspar-rich schist, the veins are planar, contain scattered sulfide minerals and visible gold, and there has been little alteration of essentially undeformed adjacent wall rock (centimetre scale). In contrast, muscovite-rich laminated schist host rock is extensively deformed and altered adjacent to mineralised faults (metre scale), with addition of quartz (silicification) and ankeritic replacement of metamorphic chlorite by kaolinite and/or sericitic muscovite. Veins adjacent to laminated (micaceous) schist contain abundant breccias with variably altered clasts. Widespread addition of auriferous sulfide minerals, mainly arsenopyrite, has occurred in the laminated schist alteration zones and breccias. The mineralised faults formed in the hinge of a northwest-trending post-metamorphic antiform, and the faults may have been localised by zones of weakness associated with kink folding in the hinge of the antiform. Hydrothermal fluids responsible for mineralisation were channelled by the normal faults. These faults developed by coalescence of extensional fractures in the schist rock mass during middle Cretaceous regional extensional unroofing of the Otago Schist belt. The location of these mineralised faults near the margin of the Otago Schist belt suggests a genetic relationship between mineralisation and the regional northwest-striking normal fault systems that cut and define the schist margin. [ABSTRACT FROM AUTHOR]

This review identifies factors that influence the development of integrated pest management (IPM) programmes and contribute to reducing risks from pesticide use. It examines how these factors may alter decisions concerning pesticide use as well as influence the choice of pesticide. The review focuses on IPM programmes in New Zealand in processing tomatoes, sweetcorn, vegetable brassicas, and potatoes, and compares these programmes with IPM in pipfruit. Factors examined include regulatory issues, markets and consumers, environment and sustainability, industry associations, the plant protection industry, growers, economic factors, science and technology, and implementation. Aalthough requirements for export markets have been a key factor driving IPM in pipfruit, this has not been the situation in most vegetable crops, but this may change as quality standards become more important across all horticultural sectors. Sustainability problems, recognised as increased reliance on pesticides, lack of natural controls, and pesticide resistance, have contributed to crisis responses but have also helped to promote industry support of IPM programmes. Underpinning science, cohesive industry associations and the availability of selective pesticides were key requirements for IPM development, but the continuation and improvement of IPM in specific crops relies on ongoing, planned extension services. [ABSTRACT FROM AUTHOR]

The Sisters shear zone is a newly discovered Late Cretaceous detachment fault system exposed for 40 km along the southeast coast of Stewart Island, southernmost New Zealand. Footwall rocks consist of variably deformed ca. 310 and 105 Ma granites that range from undeformed to protomylonite, mylonite, and ultramylonite. The hanging wall includes non- marine conglomerate and brittley deformed granite. K-feldspar thermochronometry of the footwall indicates moderately rapid cooling (20-30 C°/m.y.) due to tectonic denudation over the interval Ca. 89-82 Ma. Return to slow cooling at 82 Ma coincides with the age of the oldest seafloor adjacent to the Campbell Plateau and reflects the mechanical transition from continental extension to lithospheric rupture and formation of the Pacific-Antarctic Ridge. Our findings support a two-stage rift model for continental breakup of this part of the Gondwana margin. Stage one (ca. 101-88 Ma) is the northward propagation of continental extension and the Tasman Ridge as recorded in mylonite dredged from the Ross Sea and the Paparoa core complex. Stage two (ca. 89-82 Ma) is extension between the Campbell Plateau and West Antarctica leading to formation of the Pacific-Antarctic Ridge. [ABSTRACT FROM AUTHOR]

Abstract: In policy and innovation systems characterized by fragmented institutional arrangements, communication between system participants can be problematic. Understanding the perspectives of system participants, and sources of agreement and disagreement between them, is critical for the development strategies for change requiring collective action. The policy systems analysis and mediation (PSAM) template has been developed as an analytical approach that facilitates a shared understanding between policy and innovation system participants and better enables collaborative strategies to be developed. The PSAM template was applied in the on-farm sector of the New Zealand dairy industry in 2002–2003 in the context of industry on-farm productivity policy. It enabled key institutional interplay issues to be isolated, areas of alignment and misalignment between system participants to be identified, and it highlighted opportunities for change. The PSAM template, in augmenting existing analytical techniques, has particular value in facilitating the development of strategies for change in functionally differentiated and organizationally fragmented policy and innovation systems. [Copyright &y& Elsevier]

To understand the tectonic evolution of the southern termination of the Taupo Volcanic Zone (TVZ), New Zealand, we compare the late Quaternary structure and kinematics of the southern part of the Taupo Rift or Taupo Fault Belt (Mt Ruapehu Graben) with central parts of the rift (Ngakuru Graben), and with the South Wanganui Basin. We also investigate the differences between displacements of Pliocene and late Quaternary markers within the southern Taupo Rift. Comparison of fault displacement rates derived from displacements of late Quaternary and Pliocene markers yields a preliminary estimate of <400 000 yr for fault initiation of the majority of faults in the southern Taupo Rift. The timing of the onset of faulting in the southern TVZ appears to be younger than central parts of the TVZ and may indicate a step-wise southward propagation of the rift. Faulting also appears to be less evolved in the south than in the central parts of the Taupo Rift (thicker seismogenic crust and hence wider fault spacing), reinforcing the impression of a recent incremental propagation of the Taupo Rift to the south. The onset of faulting coincides with independent observations of the initiation of volcanism in the southern TVZ. We propose that the termination of the TVZ, geographically short of the limit of the Hikurangi margin, may only be temporary, and it is most likely to propagate southward in association with future major perturbations in the subduction margin, such as the occurrence of large ignimbrite volcanism. [ABSTRACT FROM AUTHOR]

Late Quaternary structure and kinematics at the southern termination of the Taupo Rift are investigated by means of active fault mapping and estimates of fault displacement and extension rates. Active faults in the southern Taupo Rift are normal in sense and include three major structures: the NNE-trending Mt Ruapehu Graben; the E-W to ESE-WNW-trending Ohakune-Raetihi fault set; and the NE-trending Karioi fault set. Displacements of young geomorphic features, fault plane exposures in roadcuts, and trenches across faults show that all faults are active contemporaneously. The Mt Ruapehu Graben is the southern extension of the modern (i.e., <26 ka) Taupo Rift (or Taupo Fault Belt, TFB), and has developed as a result of backarc extension related to the Hikurangi subduction margin. Geologic extension rate for the Mt Ruapehu Graben is estimated here at 2.3 ± 1.2 mm/yr. The other two structures strike almost perpendicular to the Taupo Rift terminating the Mt Ruapehu Graben to the south. The co-existence of three normal fault sets in mutual crosscutting relations and with no significant strike-slip on any of them may be related to local reorientation of the minimum principal stress axis (σ3) or to a stress tensor where |σ3| ≈ |σ2|. Complicated strains at the southern termination of the Taupo Rift are related to block rotations in the Hikurangi subduction margin. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes lessons learned from a more than 20-year involvement in formal, remunerated farmer extension and advisory work by individuals from a large commercial veterinary practice in the North Island of New Zealand. The additional skills required by veterinarians interested in undertaking extension delivery work are highlighted, as are upcoming opportunities within the New Zealand sheep industry to be involved in such work. [Copyright &y& Elsevier]