Effects of Fluid Mg/Ca And Dp18So on Geochemistry of Calcium Carbonates: Studies on Inorganic and Natural Samples

Mg/Ca and d18O derived from marine biogenic carbonates have been widely used as reliable paleoenvironmental proxy for seawater temperature, salinity and water mass circulation reconstructions. The use of Mg/Ca is based on long residence time in seawater and uniform distribution with habitat depth of...

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Bibliographic Details
Main Author: Novak, Aleksandra Vladimirovna
Format: Text
Language:unknown
Published: Scholars Junction 2016
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Online Access:https://scholarsjunction.msstate.edu/td/1747
https://scholarsjunction.msstate.edu/cgi/viewcontent.cgi?article=2746&context=td
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Summary:Mg/Ca and d18O derived from marine biogenic carbonates have been widely used as reliable paleoenvironmental proxy for seawater temperature, salinity and water mass circulation reconstructions. The use of Mg/Ca is based on long residence time in seawater and uniform distribution with habitat depth of planktonic foraminifera. Fluid Mg/Ca affects mineralogy of CaCO3, thus high seawater Mg/Ca favors precipitation of aragonite instead of calcite. The records of d18O in carbonates yield strong correlation with seawater temperature, salinity and d18O. Distribution of d18O in water is highly heterogeneous within longitude, latitude and depth. Therefore a combination of foraminieral d18O and Mg/Ca could resolve temperature, d118Owater, and hence salinity, which is linked to variability in fresh water balance and glacial ice volume throughout geologic history. In this work we study the effects of important seawater/fluid parameters on Mg/Ca in inorganic and d18O in natural samples and provide data for improving paleoceanographic reconstructions.