Trace And Rare Earth Elements Geochemistry Of Marble From Ikpeshi,Its Provenance And Paleo-Redox Conditions

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Author(s) R.A Obasi | O. L Anike | P Ogungbuyi
Pages 14-25
Volume 4
Issue 1
Date January, 2015
Keywords Baroque dolomite, mineralogy, mantle-derived, provenance.

Forty marble samples were collected from the Ikpeshi quarry pits and analyzed for major, trace rare earth elements using the Inductively coupled plasma-mass spectrometer and X-ray diffractometer methods. The diffractograms reveal the presence of calcite, dolomite, illite, smectite montmorillonite, kaolinite and quartz minerals.The trace and rare earth elements were then subjected to the multivariate statistical analysis in order to determine the elemental distribution, mineralogy and marble provenance. Ba and Sr elements are strongly enriched in the marble except in the dolomitic marble from the Golden Girl quarry area. The heavy rare earth elements (HREE) reveal depleted contents as against the high concentration of the light rare earth elements (LREE).Low concentration of the HREE with enriched LREE suggest a paleo-proterozoic age of the metamorphosed limestone. Factor analysis shows that V,Ba Sr, Zr, Co, Cu, and Rb are strongly enriched and well distributed in the marble.The high loading of Ba, Sr, Zr, Cu, and Rb is significant and is interpreted as a probable fractionation and the mineralization of calcite and dolomite in the marble in association with accessory chalcophile minerals.The enrichment of high field strength element, Zr (3.95-36 ppm), high ratio of La/Yb (2.75-54.4 ppm) and considerable amount of volatites, relatively high LREE and HREE impoverishment suggest that the carbonate-rich fluid that formed limestone that metamorphosed into marble is derived from a mantle source. The rare earth parameters such as U, U/Th and Ni/Co ratios indicate that the sediment constituents of marble were deposited under suboxic and anoxic environments.

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