Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 6 of 6 for “"silicate dissolution"”.
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Silicate weathering in the Himalayas: Constraints from the Li isotopic composition of river systems
Chemical weathering of silicate rock consumes atmospheric CO2 and supplies the oceans with cations, thereby controlling both seawater chemistry and climate. The rate of CO2 consumption is closely linked to the rate of CO2 outgassing from the planetary interior, providing a negative feedback loop …
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The chemical characterisation of authigenic carbonates from the Witbank no. 2 coal seam : environmental and diagenetic implications
… of mixing of pore waters at depth, primary silicate dissolution and later percolation of groundwaters after uplift. The overall evolution of the authigenic carbonates in the Witbank no.2 seam leads to the interpretation that the early swamp was only locally "fresh", and provides strong …
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Novel Insights into the Hydrogeochemical Evolution of Groundwater within the Transboundary Milk River Aquifer
… sulphate from pyrite oxidation, carbonate dissolution, cation exchange, and a Na-HCO₃-SO₄ water type. Zone 2, from 50–75 km, records sulphate depletion through bacterial sulphate reduction, organic matter oxidation, silicate dissolution, and transition to a Na-HCO₃ water type. Zone 3, …
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A spatial and temporal study of the carbon cycle; the role of carbonates in buffering Earth’s climate
… imbalance between volcanic degassing rates and silicate weathering. To force environmental changes in this way, such as the CO<sub>2</sub> decline observed during the Cenozoic Period (66 Myr - present), requires either a decrease in volcanic degassing, or an increase in silicate weathering and a …
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Biologically Controlled Mineralization and Demineralization of Amorphous Silica
… of this dissertation outlines those aspects of silicate metabolism that are directly relevant to the controlled biomineralization of silica in eukaryotic organisms and identifies pervasive and unanswered questions surrounding biosilica formation. Particular attention is paid to the diatoms, …
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Shelf biogeochemical interactions and feedback processes in the Benguela upwelling system
… BFM includes the carbon, nitrogen, phosphorus, silicate, iron cycles and hydrogen sulphide production, which is a known occurrence in the Namibian shelf waters. New variables, nitrite and nitrous oxide production, are added in BFM to complete the nitrogen cycle. The nitrification process in BFM …