Oceanic lithosphere carries volatiles, notably water, into the mantle through subduction at convergent plate boundaries. This subducted water exercises control on the production of magma, ...earthquakes, formation of continental crust and mineral resources. Identifying different potential fluid sources (sediments, crust and mantle lithosphere) and tracing fluids from their release to the surface has proved challenging
. Atlantic subduction zones are a valuable endmember when studying this deep water cycle because hydration in Atlantic lithosphere, produced by slow spreading, is expected to be highly non-uniform
. Here, as part of a multi-disciplinary project in the Lesser Antilles volcanic arc
, we studied boron trace element and isotopic fingerprints of melt inclusions. These reveal that serpentine-that is, hydrated mantle rather than crust or sediments-is a dominant supplier of subducted water to the central arc. This serpentine is most likely to reside in a set of major fracture zones subducted beneath the central arc over approximately the past ten million years. The current dehydration of these fracture zones coincides with the current locations of the highest rates of earthquakes and prominent low shear velocities, whereas the preceding history of dehydration is consistent with the locations of higher volcanic productivity and thicker arc crust. These combined geochemical and geophysical data indicate that the structure and hydration of the subducted plate are directly connected to the evolution of the arc and its associated seismic and volcanic hazards.
Purpose
Assessing impacts of abiotic resource use has been a topic of persistent debate among life cycle impact assessment (LCIA) method developers and a source of confusion for life cycle assessment ...(LCA) practitioners considering the different interpretations of the safeguard subject for mineral resources and the resulting variety of LCIA methods to choose from. Based on the review and assessment of 27 existing LCIA methods, accomplished in the first part of this paper series (Sonderegger et al.
2020
), this paper provides recommendations regarding the application-dependent use of existing methods and areas for future method development.
Method
Within the “global guidance for LCIA indicators and methods” project of the Life Cycle Initiative hosted by UN Environment, 62 members of the “task force mineral resources” representing different stakeholders discussed the strengths and limitations of existing LCIA methods and developed initial conclusions. These were used by a subgroup of eight members at the Pellston Workshop® held in Valencia, Spain, to derive recommendations on the application-dependent use and future development of impact assessment methods.
Results and discussion
First, the safeguard subject for mineral resources within the area of protection (AoP) natural resources was defined. Subsequently, seven key questions regarding the consequences of mineral resource use were formulated, grouped into “inside-out” related questions (i.e., current resource use leading to changes in opportunities for future users to use resources) and “outside-in” related questions (i.e., potential restrictions of resource availability for current resource users). Existing LCIA methods were assigned to these questions, and seven methods (ADP
ultimate reserves
, SOP
URR
, LIME2
endpoint
, CEENE, ADP
economic reserves
, ESSENZ, and GeoPolRisk) are recommended for use in current LCA studies at different levels of recommendation. All 27 identified LCIA methods were tested on an LCA case study of an electric vehicle, and yielded divergent results due to their modeling of impact mechanisms that address different questions related to mineral resource use. Besides method-specific recommendations, we recommend that all methods increase the number of minerals covered, regularly update their characterization factors, and consider the inclusion of secondary resources and anthropogenic stocks. Furthermore, the concept of dissipative resource use should be defined and integrated in future method developments.
Conclusion
In an international consensus-finding process, the current challenges of assessing impacts of resource use in LCA have been addressed by defining the safeguard subject for mineral resources, formulating key questions related to this safeguard subject, recommending existing LCIA methods in relation to these questions, and highlighting areas for future method development.
Consumption of seawater is rare among mammals. Following a local report of Arabian tahr drinking seawater, we collected camera trapping data to confirm and measure the frequency of seawater ...consumption by Arabian tahr. Based on herbivores’ seasonal deficiencies in sodium and other minerals and the infrequency of seawater consumption by Arabian tahr, we postulate the species uses seawater as a mineral supplement, similar to a terrestrial salt lick. As some countries protect salt licks as critical habitat features, we believe these areas where Arabian tahr can access the seashore should be similarly protected to help maintain behaviours that may contribute towards the fitness of this Endangered species.
•A local fisherman's observation of an Arabian tahr drinking seawater was confirmed using camera trapping.•Photographs of male, female and young Arabian tahr drinking seawater were obtained.•The low frequency of seawater drinking suggested that seawater may be used by Arabian tahr as a mineral resource, particularly for sodium.
This paper describes mineral resources and the demand for them, taking into account the dynamics and global trends in the economy of raw materials. It presents the importance of mineral resources in ...the development of the world economy, and the importance of mineral resources that are critical for economic development. The main assumptions presented in this paper are the main assumptions that relate to the sustainable development of the mining sector, the ones that will significantly shape the development of mining in the future.
O sensoriamento remoto tem sido cada vez mais utilizado para interpretação e caracterização de alvos na superfície da Terra, como na prospecção mineral por meio da espectrorradiometria, que visa a ...discriminação espectral de alvos específicos, a partir da sua curva espectral de reflectância. A coleção das diferentes assinaturas espectrais organiza uma biblioteca espectral, que funciona como um catálogo digital de alvos, para ser estudada e consultada para fins ambientais. Assim, foi objetivo desta pesquisa elaborar uma biblioteca de padrões espectrais como suporte a inventários de ocorrências minerais visando a caracterização da geodiversidade na Sub-Bacia de Campinas, no estado da Bahia, onde compreende as sucessões sedimentares neoproterozóicas, com ocorrência de unidades essencialmente carbonáticas do grupo Una. Foram utilizadas neste estudo uma coleção de 27 dados espectrais, com 22 amostras de rochas carbonáticas e 5 de solos, coletadas nos municípios de Morro do Chapéu, Várzea Nova e Jacobina, por meio de um espectrorradiômetro VIS-NIR-SWIR. Nos espectros das amostras de rochas, todas apresentam as bandas diagnósticas do CO32− na faixa entre 2300 nm e 2350 nm, característico dos minerais carbonáticos (calcita e/ou dolomita), além de outras absorções resultantes das impurezas comuns de se encontrar na composição desses litotipos. Os espectros de solos apresentam feições de absorção decorrentes de oxi-hidroxidos de ferro na faixa VIS-NIR e absorções de argilominerais no SWIR.
Gambling on Ore examines the development of the western mining industry from the tumultuous and violent Gold Rush to the elevation of large-scale copper mining in the early twentieth century, using ...Montana as representative of mining developments in the broader US mining west. Employing abundant new historical evidence in key primary and secondary sources, Curtis tells the story of the inescapable relationship of mining to nature in the modern world as the United States moved from a primarily agricultural society to a mining nation in the second half of the nineteenth century. In Montana, legal issues and politics-such as unexpected consequences of federal mining law and the electrification of the United States-further complicated the mining industry's already complex relationship to geology, while government policy, legal frameworks, dominant understandings of nature, and the exigencies of profit and production drove the industry in momentous and surprising directions. Despite its many uncertainties, mining became an important part of American culture and daily life. Gambling on Ore unpacks the tangled relationships between mining and the natural world that gave material possibility to the age of electricity. Metal mining has had a profound influence on the human ecology and the social relationships of North America through the twentieth century and throughout the world after World War II. Understanding how we forged these relationships is central to understanding the environmental history of the United States after 1850.
Abstract
The pipeline hydraulic transport is an important component of the deep-sea mineral resources. The characteristics of particle dynamics with coarse particles is investigated by using the ...CFD-DEM method in the vertical and inclined pipeline. The normal pipeline and abnormal pipeline mentioned in this paper refer to vertical pipeline and inclined pipeline, respectively. The particles of the normal pipeline mainly move in the middle of the pipeline, while the particles mainly concentrate on the pipeline wall in the abnormal pipeline. The velocity difference of the abnormal pipeline between liquid and particle is much greater, which can be prone to cause particle aggregation. Finally, the pipeline to be blocked can be easy to be caused by the particle aggregation in the wall of abnormal pipeline. An appropriate increase in liquid velocity can improve the phenomenon.
Soil to Foil tells the extraordinary story of aluminum. Saleem H. Ali reveals its pivotal role in the histories of scientific inquiry and technological innovation as well as its importance to ...sustainability.
PDF
