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  1. The evolution of calcite-bearing kimberlites by melt-rock reaction: evidence from polymineralic inclusions within clinopyroxene and garnet megacrysts from Lac de Gras kimberlites, Canada [Download]

    Title: The evolution of calcite-bearing kimberlites by melt-rock reaction: evidence from polymineralic inclusions within clinopyroxene and garnet megacrysts from Lac de Gras kimberlites, Canada
    Creator: Stachel, Thomas
    Description: Megacrystic (>1 cm) clinopyroxene (Cr-diopside) and garnet (Cr-pyrope) xenocrysts within kimberlites from Lac de Gras (Northwest Territories, Canada) contain fully crystallized melt inclusions. These ‘polymineralic inclusions’ have previously been interpreted to form by necking down of melts at mantle depths. We present a detailed petrographical and geochemical investigation of polymineralic inclusions and their host crystals to better understand how they form and what they reveal about the evolution of kimberlite melt. Genetically, the megacrysts are mantle xenocrysts with peridotitic chemical signatures indicating an origin within the lithospheric mantle (for the Cr-diopsides studied here ~4.6 GPa, 1015 °C). Textural evidence for disequilibrium between the host crystals and their polymineralic inclusions (spongy rims in Cr-diopside, kelyphite in Cr-pyrope) is consistent with measured Sr isotopic disequilibrium. The preservation of disequilibrium establishes a temporal link to kimberlite eruption. In Cr-diopsides, polymineralic inclusions contain phlogopite, olivine, chromite, serpentine, and calcite. Abundant fluid inclusion trails surround the inclusions. In Cr-pyropes, the inclusions additionally contain Al-spinel, clinopyroxene, and dolomite. The major and trace element compositions of the inclusion phases are generally consistent with the early stages of kimberlite differentiation trends. Extensive chemical exchange between the host phases and the inclusions is indicated by enrichment of the inclusions in major components of the host crystals, such as Cr2O3 and Al2O3. This chemical evidence, along with phase equilibria constraints, supports the proposal that the inclusions within Cr-diopside record the decarbonation reaction: dolomitic melt + diopside → forsterite + calcite + CO2, yielding the observed inclusion mineralogy and producing associated (CO2-rich) fluid inclusions. Our study of polymineralic inclusions in megacrysts provides clear mineralogical and chemical evidence for an origin of kimberlite that involves the reaction of high-pressure dolomitic melt with diopside-bearing mantle assemblages producing a lower-pressure melt that crystallizes a calcite-dominated assemblage in the crust.
    Subjects: Kimberlite, Cr-rich megacrysts, Polymineralic inclusions, Melt inclusions, Decarbonation reaction, Kimberlite evolution
    Date Created: 2016/07
  2. One tree hill/Maungakiekie: Contesting the iconography of an Auckland landscape.

    Title: One tree hill/Maungakiekie: Contesting the iconography of an Auckland landscape.
    Creator: Kearns, R. A.
    Subjects: race relations, auckland, European, politics, Maori, one tree hill
    Date Created: 2000
  3. Carbon management in New Zealand local government: Co-benefits of action and organizational resolve in the absence of government support [Download]

    Title: Carbon management in New Zealand local government: Co-benefits of action and organizational resolve in the absence of government support
    Creator: Birchall, S. Jeff
    Description: In an effort to promote public sector carbon management, in 2004, New Zealand’s (NZ) Labour-led government funded local government membership in the Communities for Climate Protection - New Zealand (CCP-NZ) program, the NZ arm of ICLEI’s Cities for Climate Protection campaign. In late 2008 the Government transitioned from a Labour-led to a National-led government, and this resulted in a shift to its climate change agenda, including the abandonment of the CCP-NZ program. This paper examines the experiences of managers from the councils involved in the CCP-NZ program to determine the cobenefits of participation in the initiative, and to assess whether councils will continue activities to mitigate their carbon footprint in the absence of Government support. The research approach consists of a series of semistructured interviews with managers responsible for the delivery of the CCPNZ program within member-councils, as well as program architects from Local Government New Zealand and ICLEI. Findings suggest that while the scheme delivered considerable co-benefits, including improved management awareness around organizational carbon management and broadened inter-council networking on carbon reduction related objectives, without Government support, overall, carbon management activities will only continue in a scaledback manner.
    Subjects: Greenhouse gas emissions, Public sector organizations, Climate change mitigation, Managers, Communities for Climate Protection
    Date Created: 2014
  4. Evolution of the New Zealand voluntary carbon market: An analysis of CarboNZero client disclosures [Download]

    Title: Evolution of the New Zealand voluntary carbon market: An analysis of CarboNZero client disclosures
    Creator: Birchall, S. Jeff
    Description: Climate change has the potential to dramatically change the world as we know, both in terms of the environment and the way in which societies operate. Public policy responses to climate change continue to evolve, with many western economies proposing mechanisms for emission reductions, for example through a tax on carbon or emissions trading schemes. In the absence of finalised regulation, organisations choosing to offset their carbon emissions are engaging in the voluntary carbon market (VCM). Through an empirical description and analysis of organizations comprising the VCM field in New Zealand, this paper provides evidence of the evolution of the carbon market as well as the level of success of CarboNZero’s certification programmes (CarboNZeroCert and CEMARSCert) in reducing organizational emissions. Examination of disclosure documents of clients of CarboNZero indicate that the growth of VCM in New Zealand is slowing down. Further, CarboNZero’s programmes were found to be only modestly effective. This research thus finds that incorporation of carbon accounting is not necessarily evidence of organizational action or improvement on climate change abatement.
    Subjects: Carbon management, Disclosures, Climate change, Greenhouse gas emissions, New Zealand, Organizations
    Date Created: 2015
  5. New Zealand's abandonment of the Carbon Neutral Public Service program [Download]

    Title: New Zealand's abandonment of the Carbon Neutral Public Service program
    Creator: Birchall, S. Jeff
    Description: In 2009, New Zealand’s (NZ) new National-led government abandoned the Carbon Neutral Public Service (CNPS) program, a Labour-led government initiative intended to help Government achieve carbon neutrality within its core agencies. This short analysis article provides an overview and brief assessment of the CNPS initiative. Drawing on relevant scholarly literature and public documents relating to NZ’s climate change agenda, this paper finds that while the CNPS program suffered from a range of challenges, it nonetheless was demonstrating results. This paper also highlights that while the Labour-led government was keen to act on climate change mitigation, under the National-led government, NZ is no longer aiming to lead on carbon neutrality. Policy relevance: As climate change mitigation policy continues to feature prominently on government agendas, it is important to understand the ethos and ambition of national programs designed to lead in thisarea. This is particularly relevant during times of political change, as demonstrated in NZ, where public sector carbon neutrality vanished with the out-going Labour-led government. This paper provides a brief analysis of the CNPS program, and highlights the National-led government’s direction on climate change mitigation.
    Subjects: Climate change policy, New Zealand, Government organizations, Carbon neutral
    Date Created: 2014
  6. Termination theory and national climate change mitigation programs [Download]

    Title: Termination theory and national climate change mitigation programs
    Creator: Birchall, S. Jeff
    Description: In 2008 New Zealand (NZ) changed from a Labour-led to a National-led Government, and this resulted in a shift to Government’s carbon emission mitigation strategy, including the abandonment of the Communities for Climate Protection and the Carbon Neutral Public Service programs. Using deLeon’s (1982) seminal model for program termination, the objective of this research is to determine why NZ’s newly elected Government discontinued these initiatives. This empirical research is investigative and probing, and comprises a series of semi-structured interviews with senior managers responsible for the delivery of the respective program within their organization. The architects of each program are also investigated. In the end, this study finds that while economic constraints and programmatic inefficiencies may have played a contributing role, political ideology is the primary rationale for the termination of the CNPS and the CCP-NZ programs.
    Subjects: Climate change policy, Carbon management, Government organizations, Carbon Neutral, Termination theory, Public sector, New Zealand
    Date Created: 2014
  7. Structural challenges that contributed to the decline of the Communities for Climate Protection program [Download]

    Title: Structural challenges that contributed to the decline of the Communities for Climate Protection program
    Creator: Birchall, S. Jeff
    Description: In 2004 New Zealand’s (NZ) Labour-led government launched the Communities for Climate Protection - NZ (CCP-NZ) programme. Following a shift in Government leadership in 2008, from Clark’s Labour-led to Key’s National-led government, the CCP-NZ programme was discontinued. Through the narratives of managers charged with the implementation and delivery of the CCP-NZ programme, this paper explores the structural challenges that contributed to the initiative's decline in NZ local government. This research contributes to the academic literature by shedding light on the outworking of a local government carbon management strategy. Additionally, this study provides policy makers and managers seeking to embark on organizational carbon mitigation the opportunity to glean insight from the experience of public sector managers responsible for the CCP-NZ programme.
    Subjects: New Zealand, Local government, Carbon management, Managers
    Date Created: 2014
  8. Late Paleozoic strike-slip faults in Maritime Canada and their role in the reconfiguration of the northern Appalachian orogen [Download]

    Title: Late Paleozoic strike-slip faults in Maritime Canada and their role in the reconfiguration of the northern Appalachian orogen
    Creator: Waldron, JWF
    Description: Major late Paleozoic faults, many with documented strike-slip motion, have dissected the Ordovician-Devonian Appalachian orogen in the Maritime Provinces of Atlantic Canada. Activity alternated between east-west faults (Minas trend) and NE-SW faults (Appalachian trend). NW-SE faults (Canso trend) were probably conjugate to Minas-trend faults. Major dextral movement, on faults with Appalachian trend, in total between 200 and 300 km, began in the Late Devonian. This movement initiated the Maritimes Basin in a transtensional environment at a releasing bend formed around a promontory in the Laurentian margin and thinned the crust, accounting for the major subsidence of the basin. Appalachian-trend strike slip continued in the Mississippian but was accompanied by major movement on E-W Minas-trend faults culminating around the Mississippian-Pennsylvanian boundary, juxtaposing the Meguma and Avalon terranes of the Appalachians close to their present-day configuration. However, strike slip continued during the Pennsylvanian-Permian interval resulting in transpressional deformation that reactivated and inverted earlier extensional faults. A final major episode of transtension, mainly sinistral, occurred during the Mesozoic opening of the Atlantic Ocean. Restoration of movements on these faults, amounting to several hundred kilometers of slip, explains anomalies in the present-day distribution of terranes amalgamated during early Paleozoic Appalachian tectonism. In the restored geometry, the Nashoba and Ellsworth terranes of Ganderia are adjacent to one another, and the Meguma terrane lies clearly outboard of Avalonia. A restored post-Acadian paleogeography, not the present-day geometry of the orogen, should be used as a basis for reconstructions of its earlier Paleozoic history.
    Subjects: Tectonics
    Date Created: 2015/11/26
  9. Smoking environments in transition: The experiences of recent Chinese migrants to Canada [Download]

    Title: Smoking environments in transition: The experiences of recent Chinese migrants to Canada
    Creator: Li, J.
    Description: International migrants experience first-hand differences between countries in terms of the social meanings, spatial regulation and prevalence of smoking. This research centred on the smoking-related perceptions, experiences and behaviours of recent migrants from China to Canada. Eight focus groups were held in Edmonton, Alberta, in July–October 2013 to explore migrants' understandings of the practices and meanings of smoking in both countries. There were 58 participants (37 non-smokers and 21 smokers), most of whom were international students. Qualitative content analysis of focus group transcripts was undertaken to identify key themes. Participants observed that smoking remains almost ubiquitous in China due to ineffective spatial restrictions and the social importance of smoking among men. By contrast, smoking bans in Canada were perceived as effective due to widespread compliance and expectations of enforcement. They were conscious that male smoking was both less prevalent and less socially valued in Canada; conversely, female smoking was perceived as more accepted in Canada than in China. There was broad agreement that smoking was tolerated in Canada, provided it occurred in appropriate places. Complying with widespread spatial restrictions brought about changes in smokers' behaviours: they smoked less often, and consumed fewer cigarettes. Because smoking was more difficult to perform, participants thought the Canadian context supported quitting. Non-smokers were enthusiastic about smoke-free environments in Canada, and had become acculturated to air that did not smell of smoke. These findings affirm the importance of comprehensive smoking bans, backed by enforcement, in contributing to the denormalisation of smoking and the protection of non-smokers.
    Subjects: second-hand smoke, migration, Canada, tobacco control, smoking, China
    Date Created: 2015
  10. Managing carbon in times of political change: The rise and fall of the New Zealand Carbon Neutral Public Service program [Download]

    Title: Managing carbon in times of political change: The rise and fall of the New Zealand Carbon Neutral Public Service program
    Creator: Birchall, S. Jeff
    Description: The New Zealand (NZ) government, under Prime Minister Helen Clark’s Labour-led administration, sought in 2007 to move government core organisa- tions towards carbon neutrality. In late 2008, the NZ government changed from a Labour-led to a National-led (traditionally more conservative) government, and this saw a shift in its carbon neutrality agenda, including the dismantling of the NZ Carbon Neutral Public Service (CNPS) program. In this paper, we explore the experiences of public servants from the lead core agencies involved in the CNPS program to investigate the rise and fall of the program in a time of political change, and to assess the evidence for Cabinet Minister Dr Nick Smith’s rationale for program termination. Our research approach comprises a series of semi- structured interviews with the lead core agencies involved in the CNPS program, as well as the program champion, former Prime Minister, Helen Clark. We find that, in spite of initial challenges, the CNPS program appeared to deliver emission reductions, financial cost savings and a range of non-financial benefits. Whilst program costs would have likely outweighed the financial savings, due to high set- up and offsetting costs, we conclude that Nick Smith’s case is unsupported by the evidence.
    Subjects: Carbon management, Policy, Public sector, Government
    Date Created: 2013