Lewis,S.E., Henderson,R.A., Dickens,G.R., Shields,G.A. and Coxhell,S.(2010): The geochemistry of primary and weathered oil shale and coquina across the Julia Creek vanadium deposit (Queensland, Australia). Miner. Deposita, 45, 599-620.

『ジュリアクリーク・バナジウム鉱床（オーストラリアのクィーンズランド州）を横切る初生および風化したオイルシェールとコキナ（未固結堆積物）の地球化学的性質』

『Abstract
　A significant resource of vanadium and molybdenum exists near Julia Creek, Australia, where the middle Cretaceous organic-rich Toolebuc Formation lies between 0 and 25 m of the surface. We present and discuss a comprehensive geochemical study of the Toolebuc Formation and its enclosing stratigraphy near Julia Creek to understand this ore deposit. V and Mo contents in fresh facies are strongly associated with total organic carbon (TOC) contents, but not with Al or CaCO3; this suggests that V and Mo were originally concentrated in the organic fraction. However, chemical extractions using H2O2 indicate that Mo was originally concentrated in pyrite. The data also suggest that V was mobilized from organic matter during early diagenesis and became associated with clays as little V was extracted by H2O2 in the fresh samples. TOC contents in the Toolebuc Formation were removed during weathering, residually enriching trace metals including V and Mo, and as a result, the TOC relationship with V and Mo disintegrates. With weathering, both V and Mo predominantly became associated with iron oxide/hydroxide phases (and possibly other unidentified phases) as these elements in the weathered facies were highly soluble in the sodium citrate-sodium dithionite digestion. Large shale-hosted V and Mo deposits such as Julia Creek offer a potentially viable alternative to the currently mined magnetite-hosted deposits. A thorough understanding of the formation and host mineral phases for V and Mo of these shale deposits, however, is critical to ensure that these valuable metals can be feasibly extracted.

Keywords: Vanadium; Molybdenum; Toolebuc Formation; Eromanga Basin; Oil shale; Coquina; Inorganic geochemistry』

Introduction
Geological setting
Local geology
Samples and methods
　Primary samples and geochemical analyses
　Supplemental samples, preparation and analyses
　Bulk rock extractions
Results
　Bulk rock mineralogy
　Bulk rock geochemistry
　Bulk rock geochemistry related to aluminosilicates (clay fraction)
　Bulk rock geochemistry related to calcite (carbonate fraction)
　Bulk rock geochemistry in relation to TOC (organic component)
　Bulk rock geochemistry in relation to sulphides/sulphates
　Trace element variation: vanadium
　Trace element variation: molybdenum
　Isocon plots
　Bulk rock extractions
Discussion
　Bulk rock extractions
　Vanadium and molybdenum hosts
Conclusions
Acknowledgements
References

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