Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 4 (1969), S. 241-247 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Zusammenfassung Die Pyrit-Lagerstätte Nairne umfaßt wenigstens fünf Horizonte cambrischer Grauwacken, Quartzite und feine Sand- bis Tonsteine. Pyrit und Magnetkies sind über eine Distanz von fast 100 km schichtgetreu, was auf einen syngenetischen Ursprung der Sulfide hinweist. Schwefelisotop-Analysen von Pyrit aus dem Tagebau-Projekt erstrecken sich über einen δS34-Bereich von −12,8 bis −20,6 Promille. Diese Anreicherung weist auf einen bakteriellen Ursprung des Schwefels hin, obgleich die Spannweite der Resultate sehr eng ist. Somit ist die „Feldvermutung“ einer syngenetisch-bakteriellen Entstehung bekräftigt.
    Notes: Abstract The Nairne Pyrite deposit occurs in at least five horizons in a succession of graywackes, quartzites, and siltstones of Cambrian age. Pyrite and pyrrhotite have been traced along bedding planes for almost 100 km suggesting, of course, a syngenetic origin for the sulfides. Sulfur isotopic analyses of samples from the Nairne Pyrite open-cut project provide δS34 values ranging from −12.8 to −20.6 permil. Such enrichment in S32, even though the spread in δS34 values is comparatively narrow, is suggestive of bacteriogenic sulfur which corroborates the geological evidence that the deposit is bacteriogenic — syngenetic in origin.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 4 (1969), S. 172-199 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Abstract Die Verteilung von Sauerstoff- und Schwefel-Isotopen in den Erzkörpern von Rosebery, Mount Farrell und Mount Lyell wurde untersucht. Die Erzkörper sind in kambrische, geosynklinale vulkanische Gesteine Westtasmaniens eingebettet. An jeder dieser Lagerstätten zeigt der Schwefel der Sulfiderze einen charakteristischen Anreicherungsgrad an δ34S im Verhältnis zum Meteoritenschwefel und einen eng begrenzten Bereich der δ34S-Werte. Die Erze des Mount Lyell-Lagers (hauptsächlich Pyrit-Chalkopyrit) zeigen überwiegend einen δ34S-Durchschnittswert von +7.0‰, das Hauptlager von Rosebery (Pyrit-Sphalerit-Galenit-Chalkopyrit) +10.9‰, und des Mount Farrell-Erz (Galenit-Sphalerit) +14.1‰. Der Anreicherungsgrad scheint nicht mit den lokalen geologischen Faktoren verbunden zu sein. Auch andere Erzkörper geosynklinaler vulkanischer Art von ähnlicher mineralogischer Struktur zeigen eng begrenzte δ34S-Werte und 34S-Anreicherungsvariationen. Der Baryt des konkordant aufgebauten Sulfid-Baryt-Carbonat-Lagers bei Rosebery hat einen δ34S-Durchschnitt von +38.1‰ und einen δ18O-Durchschnitt von +10.7‰. Der Baryt aus den Erzgängen von Mount Lyell ist durch einen δ34S-Durchschnitt von +25.3‰ und einen δ18O-Durchschnitt von +10.6‰ charakterisiert.
    Notes: Abstract Preliminary studies have been made on the distributions of oxygen and sulphur isotopes in the Rosebery, Mount Farrell, and Mount Lyell ores. These ores lie in Cambrian geosynclinal volcanic rocks in West Tasmania. At each locality the sulphur of the sulphide minerals has a distinctive degree of enrichment in δ34S in relation to sulphur in meteorites and a narrow range of δ34S values. The dominant ore at Mount Lyell (mainly pyrite-chalcopyrite) has an average δ34S value of +7.0‰, the main lode at Rosebery (pyrite-sphalerite-galenachalcopyrite) averages +10.9‰, and the Mount Farrell ore (galena-sphalerite) averages +14.1‰. The degree of enrichment does not appear to be related to local, near-surface geological factors. Other ores of geosynclinal volcanic type with similar mineralogy also show narrow ranges in δ34S and varying enrichments in 34S. Barite from a concordant sulphide-barite-carbonate lode at Rosebery has an average δ34S of +38.1‰ and an average δ18O of +10.7‰. Barite from veins at Mount Lyell has an average δ34S of +25.3‰ and an average δ18O of +10.6‰.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Cytopathology 16 (2005), S. 0 
    ISSN: 1365-2303
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Contributions to mineralogy and petrology 11 (1965), S. 405-414 
    ISSN: 1432-0967
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Stable sulfur isotopes may aid in distinguishing sulfides of a magmatic hydrothermal origin from sulfides containing biogenic sulfur. For those sulfide ore depositis that are intimately associated with the intrusive body from which it is inferred their ore solutions were derived, the variation in δS34 values is generally less than ± 5 permil. Biogenic sulfides, on the other hand, exhibit a broad spread in δS34 values that is rately less than a few permil. The reason for this is that the sulfur produced, as hydrogen sulfide by anaerobic bacteria, is isotopically fractionated by variable amounts resulting in a relatively broad spread in δS34 values. Raw culture experiments have illustrated the isotopic effects resulting from reduction of sulfate to hydrogen sulfate by sulfate reducing bacteria. The characteristics of enrichment of S32 to a highly variable extent in hydrogen sulfide is verified by these experiments. In addition, a series of closed system raw culture experiments resulted in fractionation factors between 1.043 to 1.062 which are similar to variations in δS34 between juxtaposed sulfides in nature produced by bacteriogenic processes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 14 (1979), S. 137-152 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Mobility of uranium with ground water in near surface earth conditions and its association with sandstone formations of continental depositional environments require an increase in the understanding and application of depositional characteristics in exploration. This paper, therefore, summarizes significant relationships of uranium geochemistry in the supergene environments and depositional characteristics of fluvial, deltaic, and lacustrine environments and their influence on exploration that may aid in the expeditious search for sandstone-type uranium deposits throughout the world.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...