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The Biogeochemical Cycle Of Barium. Caroline Schmidt. Table Of Content. Introduction. Behaviour Of Barium In The Deep Sea. Barite: A Glimpse At Different Genesis. What To Do With These Results !?. Further Literature. Natural Occurrence As Barite (BaSO 4 ). Ba. 56.
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The Biogeochemical Cycle Of Barium Caroline Schmidt
Table Of Content Introduction. Behaviour Of Barium In The Deep Sea. Barite: A Glimpse At Different Genesis. What To Do With These Results !? Further Literature.
Natural Occurrence As Barite (BaSO4) Ba 56 BaSO4 Ba2+ + SO42- Barite Has A Very High Density: 4.5 137,3 Use Of Barium/Barite As A Tracer For Biological Production In the Sea
How Does Barium Precipitate As Barite In The Ocean? Ba - Precipitation Because Of Decomposition Of Organic Matter Ba - Precipitation Because Of Acantharia (SrSO4) Dissolution Occurs In The Euphotic Zone (< 200m) Occurs Between 200 - 1200m
How Is Barium Related To Organic Carbon Considering The Depth? The Less The Corg - Flux, The Higher The Ba - Flux Barium Decreases With Depth Ratio Corg:Ba Is Strongly Dependent On Depth
What Are The Influences? Lateral Advection? Sinking Rapidity? Differences In Saturation? Seasonal Changes? Different Geographic Locations?
Seasonal Changes ! Differences In Ba/Corg Ratios Between The Years. (Ross Sea)
Different Geographical Location ! Differences Only In The Deeper Part - Difference In Dissolved Barium In The Water Column
Different Barites Hydrothermal B. Ba Enriched Hydrothermal Fluids React With Sea- water - Sulfate “Bio-Barite” Formation Within A Micro- environment Of Decaying Bio. Depris Diagenetic B. ??? In The Water Column
Diagenetic Barite ! Settled “Bio-Barite” Will Be Removed By Sulfate Reduction 2 H+ + SO42- + 2 (CH2O) 2 CO2 +H2S + 2 H2O Sulfate-Bearing Fluids From The Deeper Sediment Column Lead To Reprecipitation Of DIAGENETIC BARITE Process Takes Place In The Sediment Column !!!
How To Distinguish Barite And Barite? Hydrothermal Barite: 34S Value Is Almost The Same Compared To Seawater Diagenetic Barite: 34S Value Is Much Higher Compared To Seawater
Conclusions Consideration Of Different (Regional) Influences Different Locations Cannot Be Compared Strong Correlation Between Corg/Ba-Ratio And Depth; It Is Possible To Analyze The Biological Production With The Help Of The Barite Formation (Not Every Region) Barium Can Be Used As A Quantitative Proxy To Determine Biological Production
What To Do With That? If We Can Measure Relative Constant Values Over A longer Periode, We Can Derive Datas For Paleoproductivity. Paleoproductivity And Constant Datas Will Give Hints For Paleoclimate And Also For “New Production”. We Could Include These Datas For Deriving Models Of Former And Future Climate.
Literature Dymond et al.; Barium in Deep Sea Sediment: A Geochemical Proxy For Paleoproductivity; 1992 Dymond et al.; Particulate Barium Fluxes and Their Relationships To Biological Productivity;1996 Dymond et al.; Particulate Barium Fluxes In The Ross Sea; 2002 Torres et al.; Barite Fronts In Margin Sediments: A New Look at Barium Remobilization In The Zone Of Sulfate Reduction And Formation Of Heavy Barites In Diagentic Fronts; 1995 Schwitzer, Lehrbuch der Chemie, 1999 Brockhaus In 15 Bänden, 2000