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Jeffrey S Seewald - One of the best experts on this subject based on the ideXlab platform.
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geochemistry of Fluids from earth s deepest ridge crest hot springs piccard hydrothermal field mid cayman rise
Geochimica et Cosmochimica Acta, 2018Co-Authors: J M Mcdermott, Christopher R. German, Sean P Sylva, Shuhei Ono, Jeffrey S SeewaldAbstract:Abstract Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent Fluids. To investigate the role of rock composition and deep circulation conditions on Fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in High Temperature vent Fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum Temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support Fluid formation at much Higher Temperatures in the subsurface. These High Temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source Fluid feeds High Temperature vents across the entire Piccard field. High Temperature Piccard Fluid H2 abundances (19.9 mM) are even Higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely High H2 abundances can be generated from Fluid-basalt reaction occurring at very High Temperatures. Magmatic and thermogenic sources of carbon in the High Temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted Fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to High Temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods Fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured Temperature. A lack of ΣHCOOH in the relatively Higher Temperature 398 °C Beebe Vent Fluids demonstrates the Temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely High Temperature Fluid-rock reaction with mafic substrate as the dominant control on Piccard Fluid chemistry. These results expand the known diversity of vent Fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.
Christopher R. German - One of the best experts on this subject based on the ideXlab platform.
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geochemistry of Fluids from earth s deepest ridge crest hot springs piccard hydrothermal field mid cayman rise
Geochimica et Cosmochimica Acta, 2018Co-Authors: J M Mcdermott, Christopher R. German, Sean P Sylva, Shuhei Ono, Jeffrey S SeewaldAbstract:Abstract Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent Fluids. To investigate the role of rock composition and deep circulation conditions on Fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in High Temperature vent Fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum Temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support Fluid formation at much Higher Temperatures in the subsurface. These High Temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source Fluid feeds High Temperature vents across the entire Piccard field. High Temperature Piccard Fluid H2 abundances (19.9 mM) are even Higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely High H2 abundances can be generated from Fluid-basalt reaction occurring at very High Temperatures. Magmatic and thermogenic sources of carbon in the High Temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted Fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to High Temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods Fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured Temperature. A lack of ΣHCOOH in the relatively Higher Temperature 398 °C Beebe Vent Fluids demonstrates the Temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely High Temperature Fluid-rock reaction with mafic substrate as the dominant control on Piccard Fluid chemistry. These results expand the known diversity of vent Fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.
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helium isotopes at the rainbow hydrothermal site mid atlantic ridge 36 14 n
Earth and Planetary Science Letters, 2004Co-Authors: P Jeanbaptiste, E Fourre, Jeanluc Charlou, Christopher R. German, Joel RadfordknoeryAbstract:The 3He/4He ratio and helium concentration have been measured in the vent Fluids and the dispersing plume of the Rainbow hydrothermal site, on the Mid-Atlantic Ridge (MAR). The 3He/4He ratio (7.51 Ra) and 3He end-member concentration (25 pmol/kg) are in the range of observed values elsewhere on mid-ocean ridges, pointing to the relative homogeneity of the upper mantle with respect to helium isotope geochemistry. 3He is linearly correlated with methane and manganese throughout the plume, with CH4/3He and Mn/3He ratios identical to those measured in the hot Fluids. The bulk residence time of the plume in the rift valley estimated from the plume 3He budget is ∼20 days. The 3He flux transported by the plume, calculated from current-meter data, is 12.3±3 nmol/s, requiring a flux of 490 kg/s of High-Temperature Fluid. The scaling of the heat flux emitted by the Rainbow site to that of 3He, using the 3He/heat ratio measured in the hydrothermal Fluids (9.3±2×10−18 mol/J), indicates a heat output of 1320 MW. With a regional spreading rate of ∼25 mm/year, we calculate that the annual 3He flux for this section of the MAR is of the order of 0.5±0.2 mmol per kilometre of ridge per millimetre of newly formed crust. This figure compares well with the flux calculated for the neighbouring Lucky Strike segment. Although the uncertainties remain large, both fluxes are ∼40–50% above the world average (0.33 mmol/km/mm), thus supporting earlier suggestions that the intensity of the hydrothermal activity south of the Azores is Higher than expected from the regional spreading rate.
J M Mcdermott - One of the best experts on this subject based on the ideXlab platform.
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geochemistry of Fluids from earth s deepest ridge crest hot springs piccard hydrothermal field mid cayman rise
Geochimica et Cosmochimica Acta, 2018Co-Authors: J M Mcdermott, Christopher R. German, Sean P Sylva, Shuhei Ono, Jeffrey S SeewaldAbstract:Abstract Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent Fluids. To investigate the role of rock composition and deep circulation conditions on Fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in High Temperature vent Fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum Temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support Fluid formation at much Higher Temperatures in the subsurface. These High Temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source Fluid feeds High Temperature vents across the entire Piccard field. High Temperature Piccard Fluid H2 abundances (19.9 mM) are even Higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely High H2 abundances can be generated from Fluid-basalt reaction occurring at very High Temperatures. Magmatic and thermogenic sources of carbon in the High Temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted Fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to High Temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods Fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured Temperature. A lack of ΣHCOOH in the relatively Higher Temperature 398 °C Beebe Vent Fluids demonstrates the Temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely High Temperature Fluid-rock reaction with mafic substrate as the dominant control on Piccard Fluid chemistry. These results expand the known diversity of vent Fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.
Sean P Sylva - One of the best experts on this subject based on the ideXlab platform.
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geochemistry of Fluids from earth s deepest ridge crest hot springs piccard hydrothermal field mid cayman rise
Geochimica et Cosmochimica Acta, 2018Co-Authors: J M Mcdermott, Christopher R. German, Sean P Sylva, Shuhei Ono, Jeffrey S SeewaldAbstract:Abstract Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent Fluids. To investigate the role of rock composition and deep circulation conditions on Fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in High Temperature vent Fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum Temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support Fluid formation at much Higher Temperatures in the subsurface. These High Temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source Fluid feeds High Temperature vents across the entire Piccard field. High Temperature Piccard Fluid H2 abundances (19.9 mM) are even Higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely High H2 abundances can be generated from Fluid-basalt reaction occurring at very High Temperatures. Magmatic and thermogenic sources of carbon in the High Temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted Fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to High Temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods Fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured Temperature. A lack of ΣHCOOH in the relatively Higher Temperature 398 °C Beebe Vent Fluids demonstrates the Temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely High Temperature Fluid-rock reaction with mafic substrate as the dominant control on Piccard Fluid chemistry. These results expand the known diversity of vent Fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.
Shuhei Ono - One of the best experts on this subject based on the ideXlab platform.
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geochemistry of Fluids from earth s deepest ridge crest hot springs piccard hydrothermal field mid cayman rise
Geochimica et Cosmochimica Acta, 2018Co-Authors: J M Mcdermott, Christopher R. German, Sean P Sylva, Shuhei Ono, Jeffrey S SeewaldAbstract:Abstract Hosted in basaltic substrate on the ultra-slow spreading Mid-Cayman Rise, the Piccard hydrothermal field is the deepest currently known seafloor hot-spring (4957–4987 m). Due to its great depth, the Piccard site is an excellent natural system for investigating the influence of extreme pressure on the formation of submarine vent Fluids. To investigate the role of rock composition and deep circulation conditions on Fluid chemistry, the abundance and isotopic composition of organic, inorganic, and dissolved volatile species in High Temperature vent Fluids at Piccard were examined in samples collected in 2012 and 2013. Fluids from the Beebe Vents and Beebe Woods black smokers vent at a maximum Temperature of 398 °C at the seafloor, however several lines of evidence derived from inorganic chemistry (Cl, SiO2, Ca, Br, Fe, Cu, Mn) support Fluid formation at much Higher Temperatures in the subsurface. These High Temperatures, potentially in excess of 500 °C, are attainable due to the great depth of the system. Our data indicate that a single deep-rooted source Fluid feeds High Temperature vents across the entire Piccard field. High Temperature Piccard Fluid H2 abundances (19.9 mM) are even Higher than those observed in many ultramafic-influenced systems, such as the Rainbow (16 mM) and the Von Damm hydrothermal fields (18.2 mM). In the case of Piccard, however, these extremely High H2 abundances can be generated from Fluid-basalt reaction occurring at very High Temperatures. Magmatic and thermogenic sources of carbon in the High Temperature black smoker vents are described. Dissolved ΣCO2 is likely of magmatic origin, CH4 may originate from a combination of thermogenic sources and leaching of abiotic CH4 from mineral-hosted Fluid inclusions, and CO abundances are at equilibrium with the water–gas shift reaction. Longer-chained n-alkanes (C2H6, C3H8, n-C4H10, i-C4H10) may derive from thermal alteration of dissolved and particulate organic carbon sourced from the original seawater source, entrainment of microbial ecosystems peripheral to High Temperature venting, and/or abiotic mantle sources. Dissolved ΣHCOOH in the Beebe Woods Fluid is consistent with thermodynamic equilibrium for abiotic production via ΣCO2 reduction with H2 at 354 °C measured Temperature. A lack of ΣHCOOH in the relatively Higher Temperature 398 °C Beebe Vent Fluids demonstrates the Temperature sensitivity of this equilibrium. Abundant basaltic seafloor outcrops and the axial location of the vent field, along with multiple lines of geochemical evidence, support extremely High Temperature Fluid-rock reaction with mafic substrate as the dominant control on Piccard Fluid chemistry. These results expand the known diversity of vent Fluid composition, with implications for supporting microbiological life in both the modern and ancient ocean.