Rare earth elements and yttrium in calcite and pyrite of the Orlovka gold deposit (the Southern Urals)
Abstract
REE and Y patterns for calcite and pyrite of the Orlovka gold deposit were considered. Two environments, in which evolved ore-forming fluid, are determined: early high-temperature (>200-250ºC) and later low-temperature (<200ºC). The high-temperature environment characterizes conditions of fluid formation during a progressive stage of greenschist dynamometamorphism of host rocks. Positive Eu and Y anomalies in calcite are its indicator. Minerals of ore paragenesis (calcite and pyrite) formed in low-temperature conditions, which probably existed during a regressive stage. It is shown that negative Ce anomalies in calcite could be caused by fluid-limestone interaction and also by a presence of sea or meteoric water in ore formation. Values of Y/Ho ratios for calcite display a participation of sea water. Values of Y/Ho ratios for pyrite correspond to these rations for effusive and volcanogenic-sedimentary wall rocks.
About the Author
S. E. Znamensky
Institute of Geology Ufa Science Centre Russian Academy of Sciences
Russian Federation
Russian Federation
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Review
For citations:
Znamensky S.E. Rare earth elements and yttrium in calcite and pyrite of the Orlovka gold deposit (the Southern Urals). LITHOSPHERE (Russia). 2017;(1):135-141. (In Russ.)
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