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Boron isotope variations in tourmaline from hydrothermal ore deposits: A review of controlling factors and insights for mineralizing systems
No full textTourmaline group minerals are typically the predominant host of boron in hydrothermal mineral deposits. Boron is a fluid-mobile element whose isotopic composition reflects many factors that are relevant to understanding mineralizing processes, including fluid source(s), fluid-rock interaction, and formational temperature. A new compilation of 2622 published δ
11B values for tourmaline from diverse types of hydrothermal ore deposits is presented here, with the focus (2215 analyses) on seven main types: porphyry Cu-Mo-Au deposits, granite-related Sn-W deposits, IOCG deposits, orogenic Au deposits, stratabound VMS and SEDEX deposits, and sediment-hosted U deposits. The total range of δ
11B values for the seven types is −26.8 to +35.0‰. Four (granite Sn-W, orogenic Au, stratabound VMS and SEDEX) have median δ
11B values close to the continental crustal average of about −10‰. The median values for IOCG and porphyry Cu-Mo-Au deposits are higher (−3.9‰ and −2.1‰, respectively), whereas sediment-hosted U deposits have distinctly high δ
11B (median = +25.3‰). Importantly, a considerable range of δ
11B values exists for tourmaline within each deposit type, the smallest (17.8‰) for granite Sn-W deposits and the largest (48.0‰) for IOCG deposits. The boron isotope variations in tourmaline from different deposits are suggested to reflect three levels of controlling factors and how these factors operated is illustrated with a selected number of case studies. The primary factor is the composition of the boron source; secondary effects relate to fluid-tourmaline fractionation (equilibrium or Rayleigh). There are commonly also tertiary factors that depend on evolution of the specific deposit. These include fluid mixing, changing water–rock ratio and/or depositional temperature, influences of other boron-bearing minerals, and where relevant, post-ore metamorphism. Separating the effects of these factors is rarely possible from boron isotopes alone. However, the growth of multi-isotope studies of tourmaline and coexisting phases such as mica, as well as developments in modelling/experimentation of boron isotopes and element partitioning, suggest that this limitation will be overcome.
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Boron isotopes in tourmaline from hydrothermal ore systems
No full textA new compilation of published data on the boron isotope composition of hydrothermal tourmaline is presented here. The database is provided in the excel file (Trumbull_etal_B-isotopes_Tourmaline_OreDeposits.xlsx) and contains ca. 4000 boron isotope analyses of tourmaline gathered from 57 publications (see References.docx), as well as additional information about the deposit, host rocks, age and temperature of the mineralization, particulars of tourmaline occurrence, etc. The file permits filtering based on the data and all other attributes. Some filter options that may be useful are: “Publication”, “Deposit category”, “Country”, “Tourmaline host category”, “Tourmaline origin”, “Fluid source”, “Zoning”, “Mineralization”. It is important to note that the article linked to this database (“Application of boron isotopes in tourmaline to understanding hydrothermal ore systems” by Trumbull et al.; doi: https://doi.org/10.1016/j.oregeorev.2020.103682) discusses only tourmaline designated as “Hydrothermal” or “Hydrothermal?” in the database and reported in ISI-listed, English-language publications. This selection resulted in a total of 2622 d11B values reported in 49 publications.
Cite this dataset
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotopes in tourmaline from hydrothermal ore systems”, Mendeley Data, V4, doi: 10.17632/tv5y7xt9fb.4
Cite the article:
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotope variations in tourmaline from hydrothermal ore deposits: A review of controlling factors and insights for mineralizing systems”, Ore Geology Reviews, 125: 103682, doi: https://doi.org/10.1016/j.oregeorev.2020.103682
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Boron isotopes in tourmaline from hydrothermal ore systems
No full textA new compilation of published data on the boron isotope composition of hydrothermal tourmaline is presented here. The database is provided in the excel file (Trumbull_etal_B-isotopes_Tourmaline_OreDeposits.xlsx) and contains ca. 4000 boron isotope analyses of tourmaline gathered from 57 publications (see References.docx), as well as additional information about the deposit, host rocks, age and temperature of the mineralization, particulars of tourmaline occurrence, etc. The file permits filtering based on the data and all other attributes. Some filter options that may be useful are: “Publication”, “Deposit category”, “Country”, “Tourmaline host category”, “Tourmaline origin”, “Fluid source”, “Zoning”, “Mineralization”. It is important to note that the article linked to this database (“Application of boron isotopes in tourmaline to understanding hydrothermal ore systems” by Trumbull et al.; doi: xx) discusses only tourmaline designated as “Hydrothermal” or “Hydrothermal?” in the database and reported in ISI-listed, English-language publications. This selection resulted in a total of 2622 d11B values reported in 49 publications.
Cite this dataset
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotopes in tourmaline from hydrothermal ore systems”, Mendeley Data, V1, doi: 10.17632/tv5y7xt9fb.2
Cite the article:
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotope variations in tourmaline from hydrothermal ore deposits: a review of controlling factors and insights for mineralizing systems”, Ore Geology Reviews, XX:YY-ZZ, doi
Boron isotopes in tourmaline from hydrothermal ore systems
No full textA new compilation of published data on the boron isotope composition of hydrothermal tourmaline is presented here. The database is provided in the excel file (Trumbull_etal_B-isotopes_Tourmaline_OreDeposits.xlsx) and contains ca. 4000 boron isotope analyses of tourmaline gathered from 57 publications (see References.docx), as well as additional information about the deposit, host rocks, age and temperature of the mineralization, particulars of tourmaline occurrence, etc. The file permits filtering based on the data and all other attributes. Some filter options that may be useful are: “Publication”, “Deposit category”, “Country”, “Tourmaline host category”, “Tourmaline origin”, “Fluid source”, “Zoning”, “Mineralization”. It is important to note that the article linked to this database (“Application of boron isotopes in tourmaline to understanding hydrothermal ore systems” by Trumbull et al.; doi: xx) discusses only tourmaline designated as “Hydrothermal” or “Hydrothermal?” in the database and reported in ISI-listed, English-language publications. This selection resulted in a total of 2622 d11B values reported in 49 publications.
Cite this dataset
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotopes in tourmaline from hydrothermal ore systems”, Mendeley Data, V1, doi: 10.17632/tv5y7xt9fb.1
Cite the article:
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Application of boron isotopes in tourmaline to understanding hydrothermal ore systems”, Ore Geology Reviews, XX:YY-ZZ, doi
Boron isotopes in tourmaline from hydrothermal ore systems
No full textA new compilation of published data on the boron isotope composition of hydrothermal tourmaline is presented here. The database is provided in the excel file (Trumbull_etal_B-isotopes_Tourmaline_OreDeposits.xlsx) and contains ca. 4000 boron isotope analyses of tourmaline gathered from 57 publications (see References.docx), as well as additional information about the deposit, host rocks, age and temperature of the mineralization, particulars of tourmaline occurrence, etc. The file permits filtering based on the data and all other attributes. Some filter options that may be useful are: “Publication”, “Deposit category”, “Country”, “Tourmaline host category”, “Tourmaline origin”, “Fluid source”, “Zoning”, “Mineralization”. It is important to note that the article linked to this database (“Application of boron isotopes in tourmaline to understanding hydrothermal ore systems” by Trumbull et al.; doi: xx) discusses only tourmaline designated as “Hydrothermal” or “Hydrothermal?” in the database and reported in ISI-listed, English-language publications. This selection resulted in a total of 2622 d11B values reported in 49 publications.
Cite this dataset
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotopes in tourmaline from hydrothermal ore systems”, Mendeley Data, V1, doi: 10.17632/tv5y7xt9fb.2
Cite the article:
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotope variations in tourmaline from hydrothermal ore deposits: a review of controlling factors and insights for mineralizing systems”, Ore Geology Reviews, XX:YY-ZZ, doi
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Boron isotopes in tourmaline from hydrothermal ore systems
No full textA new compilation of published data on the boron isotope composition of hydrothermal tourmaline is presented here. The database is provided in the excel file (Trumbull_etal_B-isotopes_Tourmaline_OreDeposits.xlsx) and contains ca. 4000 boron isotope analyses of tourmaline gathered from 57 publications (see References.docx), as well as additional information about the deposit, host rocks, age and temperature of the mineralization, particulars of tourmaline occurrence, etc. The file permits filtering based on the data and all other attributes. Some filter options that may be useful are: “Publication”, “Deposit category”, “Country”, “Tourmaline host category”, “Tourmaline origin”, “Fluid source”, “Zoning”, “Mineralization”. It is important to note that the article linked to this database (“Application of boron isotopes in tourmaline to understanding hydrothermal ore systems” by Trumbull et al.; doi: https://doi.org/10.1016/j.oregeorev.2020.103682) discusses only tourmaline designated as “Hydrothermal” or “Hydrothermal?” in the database and reported in ISI-listed, English-language publications. This selection resulted in a total of 2622 d11B values reported in 49 publications.
Cite this dataset
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotopes in tourmaline from hydrothermal ore systems”, Mendeley Data, V4, doi: 10.17632/tv5y7xt9fb.4
Cite the article:
Trumbull, Robert B.; Codeço, Marta S.; Jiang, Shao-Yong; Palmer, Martin R.; Slack, John F. (2020), “Boron isotope variations in tourmaline from hydrothermal ore deposits: A review of controlling factors and insights for mineralizing systems”, Ore Geology Reviews, 125: 103682, doi: https://doi.org/10.1016/j.oregeorev.2020.10368
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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