The Experts below are selected from a list of 4725 Experts worldwide ranked by ideXlab platform
Robert M. Garrels - One of the best experts on this subject based on the ideXlab platform.
-
Calculated aqueous-solution-solid-solution relations in the low-temperature system CaO-MgO-FeO-CO2-H2O
Geochimica et Cosmochimica Acta, 1992Co-Authors: Terri L. Woods, Robert M. GarrelsAbstract:Abstract A method of estimating an aqueous-solution composition from that of solid-solutions believed to be in equilibrium with it is derived. The low-temperature ternary Ca-Fe-Mg phase relations of the rhombohedral carbonates are investigated using this method, and their phase diagrams at 25 and 150°C are calculated. Algebraic manipulations of equilibrium constant equations representing dissolution of the carbonates yield equations for the phase boundaries separating calcite from an Ankerite-dolomite solid-solution and an Ankerite-dolomite solid-solution from a siderite-magnesite solid-solution. A value for the free energy of formation of Ankerite is estimated (−1818.0 ± 0.8 kJ/mol, 25°C) from compositions of natural coexisting carbonates. Necessary compositional information for the carbonates was derived from the relatively unmetamorphosed Early Proterozoic Marra Mamba Banded Iron-Formation of the Hamersley Basin of Western Australia. The method yielded information on the a Fe 2+ a ca 2+ and a Mg 2+ a ca 2+ ratios of the solutions that deposited the carbonates of the Marra Mamba. The method suggests a depositing solution for the carbonates of the Lower Marra Mamba Iron-Formation significantly richer in iron than was likely to have been the case for Early Proterozoic seawater.
-
Calculated aqueous-solution-solid-solution relations in the low-temperature system CaO-MgO-FeO-CO2-H2O
Geochimica et Cosmochimica Acta, 1992Co-Authors: Terri L. Woods, Robert M. GarrelsAbstract:Abstract A method of estimating an aqueous-solution composition from that of solid-solutions believed to be in equilibrium with it is derived. The low-temperature ternary Ca-Fe-Mg phase relations of the rhombohedral carbonates are investigated using this method, and their phase diagrams at 25 and 150°C are calculated. Algebraic manipulations of equilibrium constant equations representing dissolution of the carbonates yield equations for the phase boundaries separating calcite from an Ankerite-dolomite solid-solution and an Ankerite-dolomite solid-solution from a siderite-magnesite solid-solution. A value for the free energy of formation of Ankerite is estimated (−1818.0 ± 0.8 kJ/mol, 25°C) from compositions of natural coexisting carbonates. Necessary compositional information for the carbonates was derived from the relatively unmetamorphosed Early Proterozoic Marra Mamba Banded Iron-Formation of the Hamersley Basin of Western Australia. The method yielded information on the a Fe 2+ a ca 2+ and a Mg 2+ a ca 2+ ratios of the solutions that deposited the carbonates of the Marra Mamba. The method suggests a depositing solution for the carbonates of the Lower Marra Mamba Iron-Formation significantly richer in iron than was likely to have been the case for Early Proterozoic seawater.
Terri L. Woods - One of the best experts on this subject based on the ideXlab platform.
-
Calculated aqueous-solution-solid-solution relations in the low-temperature system CaO-MgO-FeO-CO2-H2O
Geochimica et Cosmochimica Acta, 1992Co-Authors: Terri L. Woods, Robert M. GarrelsAbstract:Abstract A method of estimating an aqueous-solution composition from that of solid-solutions believed to be in equilibrium with it is derived. The low-temperature ternary Ca-Fe-Mg phase relations of the rhombohedral carbonates are investigated using this method, and their phase diagrams at 25 and 150°C are calculated. Algebraic manipulations of equilibrium constant equations representing dissolution of the carbonates yield equations for the phase boundaries separating calcite from an Ankerite-dolomite solid-solution and an Ankerite-dolomite solid-solution from a siderite-magnesite solid-solution. A value for the free energy of formation of Ankerite is estimated (−1818.0 ± 0.8 kJ/mol, 25°C) from compositions of natural coexisting carbonates. Necessary compositional information for the carbonates was derived from the relatively unmetamorphosed Early Proterozoic Marra Mamba Banded Iron-Formation of the Hamersley Basin of Western Australia. The method yielded information on the a Fe 2+ a ca 2+ and a Mg 2+ a ca 2+ ratios of the solutions that deposited the carbonates of the Marra Mamba. The method suggests a depositing solution for the carbonates of the Lower Marra Mamba Iron-Formation significantly richer in iron than was likely to have been the case for Early Proterozoic seawater.
-
Calculated aqueous-solution-solid-solution relations in the low-temperature system CaO-MgO-FeO-CO2-H2O
Geochimica et Cosmochimica Acta, 1992Co-Authors: Terri L. Woods, Robert M. GarrelsAbstract:Abstract A method of estimating an aqueous-solution composition from that of solid-solutions believed to be in equilibrium with it is derived. The low-temperature ternary Ca-Fe-Mg phase relations of the rhombohedral carbonates are investigated using this method, and their phase diagrams at 25 and 150°C are calculated. Algebraic manipulations of equilibrium constant equations representing dissolution of the carbonates yield equations for the phase boundaries separating calcite from an Ankerite-dolomite solid-solution and an Ankerite-dolomite solid-solution from a siderite-magnesite solid-solution. A value for the free energy of formation of Ankerite is estimated (−1818.0 ± 0.8 kJ/mol, 25°C) from compositions of natural coexisting carbonates. Necessary compositional information for the carbonates was derived from the relatively unmetamorphosed Early Proterozoic Marra Mamba Banded Iron-Formation of the Hamersley Basin of Western Australia. The method yielded information on the a Fe 2+ a ca 2+ and a Mg 2+ a ca 2+ ratios of the solutions that deposited the carbonates of the Marra Mamba. The method suggests a depositing solution for the carbonates of the Lower Marra Mamba Iron-Formation significantly richer in iron than was likely to have been the case for Early Proterozoic seawater.
Stuart R Haszeldine - One of the best experts on this subject based on the ideXlab platform.
-
co2 sequestration by mineral trapping in natural analogues in the yinggehai basin south china sea
Marine and Petroleum Geology, 2019Co-Authors: Niklas Heinemann, Mark Wilkinson, Zhenfeng Wang, Stuart R HaszeldineAbstract:Abstract Mineral trapping of CO2 by precipitation of carbonate minerals is seen as the most permanent and secure mechanism of CO2 storage. We have investigated mineral trapping in CO2-rich siliciclastic reservoirs of the Upper Miocene age in the Yinggehai Basin (South China Sea) and used nearby CO2-poor reservoirs of similar age as benchmarks for the analysis. Within the reservoir, the CO2 has triggered the reaction from calcite plus chlorite to Ankerite plus kaolinite, which traps 5 mol of CO2 per mole of chlorite. Geochemical modelling shows that the total amount of permanently trapped CO2 is approximately one half of the CO2 in the newly formed Ankerite. Caprock mineralogy shows that CO2 leakage has occurred and CO2 has migrated into the shale-rich caprock, but without loss of caprock integrity.
Eric H. Oelkers - One of the best experts on this subject based on the ideXlab platform.
-
Dawsonite and Ankerite formation in the LDX-1 structure, Yinggehai basin, South China sea: An analogy for carbon mineralization in subsurface sandstone aquifers
Applied Geochemistry, 2020Co-Authors: Li Liu, Na Liu, Xiaoran Ming, Eric H. OelkersAbstract:Abstract The geochemistry and petrology of the LDX-1 structure of the Yinggehai basin, a natural analog of a sedimentary carbon storage site, was investigated to understand the consequences of the charging of CO2 gas in this system. The rocks in this structure are dominated by subarkose and sublitharenite sandstones. The authigenic minerals formed after CO2 injection are dawsonite, microcrystalline quartz, kaolinite and Ankerite. Dawsonite and Ankerite are formed just beneath a CO2 bearing anticlinal structure due to the reactions between silicate minerals (feldspars and clay minerals) and the fluid phase. Carbon and oxygen isotopic analyses indicate that the main carbon source for dawsonite and Ankerite formation was mantle magmatic CO2. The aqueous activities of sodium and calcium, the partial pressure of CO2, pH and temperature are the key factors influencing the stability of the dawsonite and Ankerite. The presence of the anticlinal structure, maintaining a locally high CO2 partial pressure in the waters beneath this structure, is likely responsible for the observed long-term persistence of dawsonite and Ankerite in this system.
Niklas Heinemann - One of the best experts on this subject based on the ideXlab platform.
-
co2 sequestration by mineral trapping in natural analogues in the yinggehai basin south china sea
Marine and Petroleum Geology, 2019Co-Authors: Niklas Heinemann, Mark Wilkinson, Zhenfeng Wang, Stuart R HaszeldineAbstract:Abstract Mineral trapping of CO2 by precipitation of carbonate minerals is seen as the most permanent and secure mechanism of CO2 storage. We have investigated mineral trapping in CO2-rich siliciclastic reservoirs of the Upper Miocene age in the Yinggehai Basin (South China Sea) and used nearby CO2-poor reservoirs of similar age as benchmarks for the analysis. Within the reservoir, the CO2 has triggered the reaction from calcite plus chlorite to Ankerite plus kaolinite, which traps 5 mol of CO2 per mole of chlorite. Geochemical modelling shows that the total amount of permanently trapped CO2 is approximately one half of the CO2 in the newly formed Ankerite. Caprock mineralogy shows that CO2 leakage has occurred and CO2 has migrated into the shale-rich caprock, but without loss of caprock integrity.
