2,868 research outputs found
P-T-X conditions of fluids in the Sunrise Dam Gold Deposit, Western Australia: implications for the interplay between deformation and fluids in the orogenic gold systems
[Extract] The formation of orogenic gold deposits is generally described as a complex interplay between deformation, permeability, rock strength and hydrothermal fluid pressure. Despite it being widely known that orogenic gold deposits form from low salinity, carbon dioxide-bearing fluids, the importance of this fluid composition in the context of the physical processes of deformation and fluid behaviour is commonly overlooked. In this study we combined fluid inclusion research with structural and numerical modeling in order to link these processes in the world class (10Moz.) Late Archean Sunrise Dam gold deposit
Requirements for minerals and metals for 100% renewable scenarios
© The Author(s) 2019. This chapter explores the magnitude of the changes in patterns of material use that will be associated with the increasing deployment of renewable energy and discusses the implications for sustainable development. In particular, this chapter focuses on the increased use of lithium and cobalt, metals which are used extensively in battery technologies, and silver used in solar cells. Consistent with the strong growth in renewable energy and electrification of the transport system required in a 1.5°C scenario, the material requirements also rise dramatically, particularly for cobalt and lithium. Scenarios developed for this study show that increasing recycling rates and material efficiency can significantly reduce primary demand for metals
Recruiting and retaining community researchers for a historical research project
This article explores how we recruited and retained a diverse group of community researchers from groups who faced barriers to engaging with research. All were mothers of preschool or primary age children, and fitted one or more of the following criteria: single parent, English as an additional language, first-generation migrant, inner-city resident. We explore the process of recruitment, and making the project accessible, as well as describing the factors that allowed researchers to remain engaged with the project over the course of a year. A dedicated community support worker played a crucial role in resolving barriers to participation, and supporting researchers’ well-being and personal development once they were in the group. The article identifies five key challenges encountered across the lifetime of the project, and the strategies we used to address them. We hope our reflections and practical suggestions will make a contribution to the understanding of how people with multiple accessibility challenges can be supported to take part in, and make an essential contribution to, community–university research projects
Policy options to streamline the carbon market for agricultural nitrous oxide emissions
The majority of emissions of nitrous oxide – a potent greenhouse gas (GHG) – are from agricultural sources, particularly nitrogen fertilizer applications. A growing focus on these emission sources has led to the development in the United States of GHG offset protocols that could enable payment to farmers for reducing fertilizer use or implementing other nitrogen management strategies. Despite the development of several protocols, the current regional scope is narrow, adoption by farmers is low, and policy implementation of protocols has a significant time lag. Here we utilize existing research and policy structures to propose an ‘umbrella’ approach for nitrogen management GHG emissions protocols that has the potential to streamline the policy implementation and acceptance of such protocols. We suggest that the umbrella protocol could set forth standard definitions common across multiple protocol options, and then modules could be further developed as scientific evidence advances. Modules could be developed for specific crops, regions, and practices. We identify a policy process that could facilitate this development in concert with emerging scientific research and conclude by acknowledging potential benefits and limitations of the approach. Key policy insights Agricultural greenhouse gas market options are growing, but are still underutilized Streamlining protocol development through an umbrella process could enable quicker development of protocols across new crops, regions, and practices Effective protocol development must not compromise best available science and should follow a rigorous pathway to ensure appropriate implementation
Global Metal Use Targets in Line with Climate Goals.
Metals underpin essential functions in modern society, yet their production currently intensifies climate change. This paper develops global targets for metal flows, stocks, and use intensity in the global economy out to 2100. These targets are consistent with emissions pathways to achieve a 2 °C climate goal and cover six major metals (iron, aluminum, copper, zinc, lead, and nickel). Results indicate that despite advances in low-carbon metal production, a transformative system change to meet the society's needs with less metal is required to remain within a 2 °C pathway. Globally, demand for goods and services over the 21st century needs to be met with approximately 7 t/capita of metal stock-roughly half the current level in high-income countries. This systemic change will require a peak in global metal production by 2030 and deep decoupling of economic growth from both metal flows and stocks. Importantly, the identified science-based targets are theoretically achievable through such measures as efficient design, more intensive use, and longer product lifetime, but immediate action is crucial before middle- and low-income countries complete full-scale urbanization
Decentralised energy futures: The changing emissions reduction landscape
© 2015 The Authors. Published by Elsevier B.V. The world is witnessing an energy revolution as renewables become more competitive and energy security becomes a high priority for an increasing number of countries. This development is changing the point along the supply chain ripe for reducing emissions. Whereas carbon capture and storage (CCS) coupled to coal or gas power production offers the potential to decarbonise the current centralised power systems, this relies on a significant increase in electrification to achieve deep emission reductions beyond the power sector, including industrial emissions and transportation. At the same time there is a trend towards decentralised industrial processes, e.g., driven by cost reductions in decentralised production systems and miniature processing plant. New strategies for reducing emissions from decentralised industrial and energy emission point sources will be increasingly important. This paper evaluates different emission reduction strategies that may be relevant to a decentralised energy and manufacturing future, including increased electrification, energy storage, renewable energy and renewable feedstock. Systemic opportunities or barriers and considerations of policy and decentralised decision-making are examined
Total material requirement for the global energy transition to 2050: A focus on transport and electricity
© 2019 The Author(s) Global energy transitions could fundamentally change flows of both minerals and energy resources over time. It is, therefore, increasingly important to holistically and dynamically capture the impacts of large-scale energy transitions on resource flows including hidden flows such as mine waste, as well as direct flows. Here we demonstrate a systematic model that can quantify resource flows of both minerals and energy resources under the energy transition by using stock-flow dynamics and the concept of Total Material Requirement (TMR). The proposed model was applied to the International Energy Agency's scenarios up to 2050, targeting 15 electricity generation and 5 transport technologies. Results indicate that the global energy transition could increase TMR flows associated with mineral production by around 200–900% in the electricity sector and 350–700% in the transport sector respectively from 2015 to 2050, depending on the scenarios. Such a drastic increase in TMR flows is largely associated with an increased demand for copper, silver, nickel, lithium and cobalt, as well as steel. Our results highlight that the decarbonization of the electricity sector can reduce energy resource flows and support the hypothesis that the expansion of low-carbon technologies could reduce total resource flows expressed as TMR. In the transport sector, on the other hand, the dissemination of Electric Vehicles could cause a sharp increase in TMR flows associated with mineral production, which could offset a decrease in energy resource flows. Findings in this study emphasize that a sustainable transition would be unachievable without designing resource cycles with a nexus approach
Critical minerals and energy-impacts and limitations of moving to unconventional resources
© 2016 by the authors. The nexus of minerals and energy becomes ever more important as the economic growth and development of countries in the global South accelerates and the needs of new energy technologies expand, while at the same time various important minerals are declining in grade and available reserves from conventional mining. Unconventional resources in the form of deep ocean deposits and urban ores are being widely examined, although exploitation is still limited. This paper examines some of the implications of the transition towards cleaner energy futures in parallel with the shifts through conventional ore decline and the uptake of unconventional mineral resources. Three energy scenarios, each with three levels of uptake of renewable energy, are assessed for the potential of critical minerals to restrict growth under 12 alternative mineral supply patterns. Under steady material intensities per unit of capacity, the study indicates that selenium, indium and tellurium could be barriers in the expansion of thin-film photovoltaics, while neodymium and dysprosium may delay the propagation of wind power. For fuel cells, no restrictions are observed
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Lake Roosevelt Fisheries Evaluation Program : Lake Whatcom Kokanee Salmon (Oncorhynchus nerka kennerlyi) : Investigations in Lake Roosevelt Annual Report 1999-2000.
Lake Whatcom stock kokanee have been planted in Lake Roosevelt since 1988 with the primary goal of establishing a self-sustaining fishery. Returns of hatchery kokanee to egg collection facilities and recruitment to the creel have been minimal. Therefore, four experiments were conducted to determine the most appropriate release strategy that would increase kokanee returns. The first experiment compared morpholine and non-morpholine imprinted kokanee return rates, the second experiment compared early and middle run Whatcom kokanee, the third experiment compared early and late release dates, and the fourth experiment compared three net pen release strategies: Sherman Creek hatchery vs. Sherman Creek net pens, Colville River net pens vs. Sherman Creek net pens, and upper vs. lower reservoir net pen releases. Each experiment was tested in three ways: (1) returns to Sherman Creek, (2) returns to other tributaries throughout the reservoir, and (3) returns to the creel. Chi-square analysis of hatchery and tributary returns indicated no significant difference between morpholine imprinted and non-imprinted fish, early run fish outperformed middle run fish, early release date outperformed late release fish, and the hatchery outperformed all net pen releases. Hatchery kokanee harvest was estimated at 3,323 fish, which was 33% of the total harvest. Return rates (1998 = 0.52%) of Whatcom kokanee were low indicating an overall low performance that could be caused by high entrainment, predation, and precocity. A kokanee stock native to the upper Columbia, as opposed to the coastal Whatcom stock, may perform better in Lake Roosevelt
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