Alumina to Zirconia

2001 ◽  
Author(s):  
IJ Bear ◽  
T Biegler ◽  
TR Scott
Keyword(s):  
Close Association ◽  
Mineral Chemistry ◽  
Support Staff ◽  
Technological Research ◽  
History Of ◽  
World Class ◽  
Australian Science ◽  
Utilization Section ◽  
Technological Achievement ◽  
Csiro Division

Alumina to Zirconia is a history of the CSIRO Division of Mineral Chemistry, and tells the story of a significant part of Australia's mineral heritage. This history draws on the authors' long associations with the Division, anecdotal material, scattered records and photographs. What unfolds is a fascinating history of the Division of Mineral Chemistry, from its war-time origins as the Minerals Utilization Section in 1940, through several organisational changes under the guidance of four chiefs, until the end of 1987, when the name of the Division was changed to Mineral Products. In telling the story, Dr Joy Bear and her co-authors outline many of the main projects undertaken, highlight the achievements as well as the difficulties encountered in both the scientific and technological research itself, and in the commercialisation of newly developed processes. They also acknowledge the vital contributions of support staff, and acknowledge the close association of the Division with, and the contribution to research by, the Australian minerals industry. This is a story of scientific and technological achievement of the highest order. Alumina to Zirconia is essential reading for all those interested in the history of Australian science and its role in supporting the development of Australia's world class minerals industry.

U-Pb DATING OF HYDROTHERMAL TITANITE RESOLVES MULTIPLE PHASES OF PROPYLITIC ALTERATION IN THE OYU TOLGOI PORPHYRY DISTRICT, MONGOLIA

2020 ◽  
Vol 115 (8) ◽  
pp. 1605-1618
Author(s):  
Lisa Hart-Madigan ◽  
Jamie J. Wilkinson ◽  
Stephanie Lasalle ◽  
Robin N. Armstrong
Keyword(s):  
Inductively Coupled Plasma ◽  
Mineral Chemistry ◽  
Geodynamic Setting ◽  
Porphyry Deposits ◽  
Inductively Coupled ◽  
Close Proximity ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Propylitic Alteration ◽  
World Class

Abstract Oyu Tolgoi is a world-class, Late Devonian porphyry district in southern Mongolia. Because of its age and geodynamic setting, it has undergone a complex geological history that includes major postmineralization magmatic-hydrothermal events in close proximity to the porphyry deposits. The propylitic alteration halos that surround the Cu-Au deposits contain widespread hydrothermal titanite, as do the younger altered volcanic and intrusive rocks. Here, we present a comprehensive laser ablation-inductively coupled plasma-mass spectrometry U-Pb study on in situ, propylitic titanite from the Oyu Tolgoi district. The results identify district-wide hydrothermal alteration episodes that coincide with known magmatic events: Devonian porphyry mineralization (~372 Ma); the intrusion of granodiorite plutons and andesite dikes in the Carboniferous (~320–310 Ma); and the emplacement of the Permian Khanbogd Granite alkaline batholith (~290 Ma). Both Carboniferous and Permian alteration events variably overprint the earlier porphyry alteration halo. Overdispersion in the U-Pb data from some samples, due to Pb and/or U mobility, makes interpretation of some titanite ages more difficult, but further exemplifies the complex alteration history of the district. We conclude that U-Pb dating of propylitic titanite is a viable means by which explorers can identify alteration within a prospect that is synchronous with potentially fertile intrusions of known age. The extent of the coeval propylitic alteration and its mineral chemistry can then be used to assess the likelihood of a major porphyry center being present.

Northeast India as an Indigenous Centre for the Domestication of Plants and Animals

2017 ◽  
Author(s):  
Manjil Hazarika
Keyword(s):  
South Asian ◽  
Close Association ◽  
Northeast India ◽  
Indian Culture ◽  
Rice Agriculture ◽  
Animal Domestication ◽  
History Of ◽  
The Relationship ◽  
Diverse Cultures

Northeast India is situated at the nexus of the South Asian, Southeast Asian, and East Asian biogeographical realms and harbours diverse biota, providing a unique opportunity to archaeologists and anthropologists for the study of the relationship between humans and their environment over the ages. Moreover, this region, the abode of diverse ethnic groups with diverse cultures and customs, hints at a long history of continuous and close association between humans and nature, which is important in the understanding of plant and animal domestication. Genetic analysis of present-day domesticates with their wild counterparts provides valuable insights into their differentiation, time of domestication, and changes in their morphological traits through control by humans. The chapter also elucidates the role played by rice in Northeast Indian culture and highlights the long-term history of rice agriculture in the region.

The Metasomatized Mantle beneath the North Atlantic Craton: Insights from Peridotite Xenoliths of the Chidliak Kimberlite Province (NE Canada)

2019 ◽  
Vol 60 (10) ◽  
pp. 1991-2024 ◽  
Author(s):  
M G Kopylova ◽  
E Tso ◽  
F Ma ◽  
J Liu ◽  
D G Pearson
Keyword(s):  
North Atlantic ◽  
Thermal State ◽  
Mineral Chemistry ◽  
Mantle Metasomatism ◽  
Labrador Sea ◽  
The North ◽  
Rock Types ◽  
History Of ◽  
The North Atlantic ◽  
North Atlantic Craton

Abstract We studied the petrography, mineralogy, thermobarometry and whole-rock chemistry of 120 peridotite and pyroxenite xenoliths collected from the 156–138 Ma Chidliak kimberlite province (Southern Baffin Island). Xenoliths from pipes CH-1, -6, -7 and -44 are divided into two garnet-bearing series, dunites–harzburgites–lherzolites and wehrlites–olivine pyroxenites. Both series show widely varying textures, from coarse to sheared, and textures of late formation of garnet and clinopyroxene. Some samples from the lherzolite series may contain spinel, whereas wehrlites may contain ilmenite. In CH-6, rare coarse samples of the lherzolite and wehrlite series were derived from P = 2·8 to 5·6 GPa, whereas predominant sheared and coarse samples of the lherzolite series coexist at P = 5·6–7·5 GPa. Kimberlites CH-1, -7, -44 sample mainly the deeper mantle, at P = 5·0–7·5 GPa, represented by coarse and sheared lherzolite and wehrlite series. The bulk of the pressure–temperature arrays defines a thermal state compatible with 35–39 mW m–2 surface heat flow, but a significant thermal disequilibrium was evident in the large isobaric thermal scatter, especially at depth, and in the low thermal gradients uncharacteristic of conduction. The whole-rock Si and Mg contents of the Chidliak xenoliths and their mineral chemistry reflect initial high levels of melt depletion typical of cratonic mantle and subsequent refertilization in Ca and Al. Unlike the more orthopyroxene-rich mantle of many other cratons, the Chidliak mantle is rich (∼83 vol%) in forsteritic olivine. We assign this to silicate–carbonate metasomatism, which triggered wehrlitization of the mantle. The Chidliak mantle resembles the Greenlandic part of the North Atlantic Craton, suggesting the former contiguous nature of their lithosphere before subsequent rifting into separate continental fragments. Another, more recent type of mantle metasomatism, which affected the Chidliak mantle, is characterized by elevated Ti in pyroxenes and garnet typical of all rock types from CH-1, -7 and -44. These metasomatic samples are largely absent from the CH-6 xenolith suite. The Ti imprint is most intense in xenoliths derived from depths equivalent to 5·5–6·5 GPa where it is associated with higher strain, the presence of sheared samples of the lherzolite series and higher temperatures varying isobarically by up to 200 °C. The horizontal scale of the thermal-metasomatic imprint is more ambiguous and could be as regional as tens of kilometers or as local as <1 km. The time-scale of this metasomatism relates to a conductive length-scale and could be as short as <1 Myr, shortly predating kimberlite formation. A complex protracted metasomatic history of the North Atlantic Craton reconstructed from Chidliak xenoliths matches emplacement patterns of deep CO2-rich and Ti-rich magmatism around the Labrador Sea prior to the craton rifting. The metasomatism may have played a pivotal role in thinning the North Atlantic Craton lithosphere adjacent to the Labrador Sea from ∼240 km in the Jurassic to ∼65 km in the Paleogene.

Showcasing Science

2019 ◽  
Author(s):  
Martin Weiss
Keyword(s):  
Nineteenth Century ◽  
Art Museum ◽  
Scientific Instrument ◽  
The Public ◽  
Public Role ◽  
Electrostatic Generator ◽  
History Of ◽  
World Class ◽  
Hendrik Antoon Lorentz ◽  
Set Up

Teylers Museum was founded in 1784 and soon thereafter became one of the most important centres of Dutch science. The Museum’s first director, Martinus van Marum, famously had the world’s largest electrostatic generator built and set up in Haarlem. This subsequently became the most prominent item in the Museum’s world-class, publicly accessible, and constantly growing collections. These comprised scientific instruments, mineralogical and palaeontological specimens, prints, drawings, paintings, and coins. Van Marum’s successors continued to uphold the institution’s prestige and use the collections for research purposes, while it was increasingly perceived as an art museum by the public. In the early twentieth century, the Nobel Prize laureate Hendrik Antoon Lorentz was appointed head of the scientific instrument collection and conducted experiments on the Museum’s premises. Showcasing Science: A History of Teylers Museum in the Nineteenth Century charts the history of Teylers Museum from its inception until Lorentz’ tenure. From the vantage point of the Museum’s scientific instrument collection, this book gives an analysis of the changing public role of Teylers Museum over the course of the nineteenth century.

scholarly journals Different Tectonic Evolution of Fast Cooling Ophiolite Mantles Recorded by Olivine-Spinel Geothermometry: Case Studies from Iballe (Albania) and Nea Roda (Greece)

Minerals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 64
Author(s):  
Micol Bussolesi ◽  
Giovanni Grieco ◽  
Alessandro Cavallo ◽  
Federica Zaccarini
Keyword(s):  
Tectonic Evolution ◽  
Early Stage ◽  
Mineral Chemistry ◽  
Northern Greece ◽  
Present Contribution ◽  
Cooling Rates ◽  
History Of ◽  
Ferrian Chromite ◽  
Fast Cooling ◽  
Subduction Setting

Mg-Fe2+ diffusion patterns in olivine and chromite are useful tools for the study of the thermal history of ultramafic massifs. In the present contribution, we applied the exponential modeling of diffusion patterns to geothermometry and geospeedometry of chromitite ores from two different ophiolite contexts. The Iballe ophiolite (Northern Albania) hosts several chromitite pods within dunites. Primary and re-equilibrated Mg#, estimated by using an exponential function, provided re-equilibration and primary temperatures ranging between 677 and 996 °C for chromitites and between 527 and 806 °C for dunites. Cooling rates for chromitites are higher than for dunites, suggesting a different genesis for the two lithologies, confirmed also by spinel mineral chemistry. Chromitites with MORB affinity formed in a SSZ setting at a proto-forearc early stage, explaining the higher cooling rates, while dunites, with boninitic affinity, were formed deeper in the mantle in a more mature subduction setting. At the Nea Roda ophiolite (Northern Greece) olivine in chromitites do not show Mg-Fe variations, and transformation into ferrian chromite produced “fake” diffusion patterns within chromite. The absence of diffusion patterns and the low estimated temperatures (550–656 °C) suggest that Nea Roda chromitites were completely re-equilibrated during an amphibolite-facies metamorphic event that obliterated all primary features.

scholarly journals A world class academy in professional football:

2020 ◽  
Vol 2 ◽  
pp. 33-43
Author(s):  
Carsten Hvid Larsen ◽  
Louise Kamuk Storm ◽  
Stig Arve Sæther ◽  
Nicklas Pyrdol ◽  
Kristoffer Henriksen
Keyword(s):  
Talent Development ◽  
Individual Development ◽  
Ecological Approach ◽  
Football Players ◽  
Development Environment ◽  
History Of ◽  
World Class ◽  
Dual Careers ◽  
The Individual ◽  
Athletic Development

The holistic ecological approach puts an emphasis on the environment in which prospective elite athletes develop. Applying the holistic ecological approach, this article examines talent development among male under-19 football players at Ajax Amsterdam which has a history of successfully developing several of its juniors to top-level international players. Principal methods of data collection include interviews, participant observations of daily life in the environment, and analysis of documents. The environment was centred around the relationship between players and a clubhouse community consisting of a team of coaches, teachers, experts, and managers that helped the players to focus on: Handling dual careers (sport and school), developing mental toughness, social skills and work ethic. Furthermore, the environment was characterised by a strong, open, and cohesive organisational culture based on each player as an investment, social responsibility and individual development before winning matches. We argue that the holistic ecological approach holds the potential to inspire coaches and practitioners to be sensitive to and analyse not only the individual player’s athletic development but also the overall strategies and organisational settings, in the talent development environment.

scholarly journals Petrology, mineral chemistry, and geochemistry of Late Triassic Ni–Cu ore-bearing mafic–ultramafic intrusions, Hongqiling, northeastern China: petrogenesis and tectonic implications

2019 ◽  
Vol 56 (2) ◽  
pp. 111-128
Author(s):  
Ai Li ◽  
Jian Wang ◽  
Yue Song
Keyword(s):  
Crustal Contamination ◽  
Parental Magma ◽  
Mineral Chemistry ◽  
Late Triassic ◽  
Sulfide Deposit ◽  
Chemical Compositions ◽  
Tholeiitic Magma ◽  
Average Value ◽  
Central Asian ◽  
History Of

The Hongqiling magmatic Ni–Cu sulfide deposit, situated on the southern margin of the eastern Central Asian Orogenic Belt (CAOB), is composed of over 30 mafic–ultramafic intrusions. These ore-bearing intrusions are composed mainly of harzburgite, lherzolite, websterite, orthopyroxenite, and norite (gabbro). The constituent minerals are olivine, diopside, bronzite, calcic-hornblende, plagioclase, and spinel with orthopyroxene as a dominant mineral in these intrusions. These ore-bearing intrusions are not Alaskan-type complexes. Spinel and clinopyroxene both exhibit different chemical compositions from those in the Alaskan-type complexes. The rocks that make up the intrusions have high contents of MgO (average value = 25.20 wt.%) and low TiO2 (average value = 0.58 wt.%). The high MgO contents of the minerals and the high Mg# (71) of the calculated melt in equilibrium with olivine demonstrate that the parental magma of the Hongqiling mafic–ultramafic intrusions was a high-Mg tholeiitic magma. The Hongqiling ore-bearing mafic–ultramafic intrusions and the calculated “trapped liquids” for the olivine-orthopyroxene cumulate rocks are all enriched in large-ion lithophile elements and depleted in high field strength elements. The Ce/Pb, Ta/La, Th/Yb, and (La/Sm)PM values and the depletion of Nb and Ta suggest that the magma experienced crustal contamination. The Hongqiling ore-bearing intrusions display many similarities with mafic–ultramafic intrusions that formed in a post-collisional extensional environment in the western CAOB (e.g., Huangshanxi). Common features include their whole-rock compositions and mineral chemistry. Combined with the evolutionary history of the eastern segment of the CAOB, we believe that the Late Triassic Hongqiling mafic–ultramafic intrusions formed in a post-collisional extensional environment.

scholarly journals The International 
General Game Playing Competition

AI Magazine ◽  
2013 ◽  
Vol 34 (2) ◽  
pp. 107 ◽  
Author(s):  
Michael Genesereth ◽  
Yngvi Björnsson
Keyword(s):  
Artificial Intelligence ◽  
Problem Solving ◽  
General Problem ◽  
Game Playing ◽  
Test Bed ◽  
General Game Playing ◽  
Research Challenges ◽  
History Of ◽  
World Class ◽  
General Game

Games have played a prominent role as a test-bed for advancements in the field of Artificial Intelligence ever since its foundation over half a century ago, resulting in highly specialized world-class game-playing systems being developed for various games. The establishment of the International General Game Playing Competition in 2005, however, resulted in a renewed interest in more general problem solving approaches to game playing. In general game playing (GGP) the goal is to create game-playing systems that autonomously learn how to skillfully play a wide variety of games, given only the descriptions of the game rules. In this paper we review the history of the competition, discuss progress made so far, and list outstanding research challenges.

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