Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Labo-ratory of Marine...Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Labo-ratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREE<21×10?9), and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite, implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration. The sulfur isotopic compo-sitions of the native sulfur samples reveal that the sulfur of the chimney, from H2S and SO2, originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao ande-site and partly from seawater. Combining these results with an analysis of the thermodynamics, it is clear that from the relatively low temperature (<116 ℃ ), the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.展开更多
The rare earth element(REE)geochemistry of hydrothermal vent systems has been investigated intensively,but few studies have been carried out on marine shallow-water hydrothermal systems like that at Kueishantao.Here w...The rare earth element(REE)geochemistry of hydrothermal vent systems has been investigated intensively,but few studies have been carried out on marine shallow-water hydrothermal systems like that at Kueishantao.Here we present novel data sets of REE in hydrothermal fluids from Kueishantao,off northeastern Taiwan.The total REE(REE)concentrations of yellowish fluids are similar to those of whitish fluids,813–1212 ng/L,and are significantly higher than that of ambient seawater.The yellowish fluids have chondrite-normalized REE(REEN)distribution patterns with slight convex-downward curvatures at Eu;and the REE patterns of the whitish fluids are smooth at Eu,which is related to the lower temperature and more oxidizing conditions.The Kueishantao hydrothermal fluids are slightly enriched in light REE(La-Nd)relative to the heavy REE(Gd-Lu).The behaviors of REE in both yellowish and whitish fluids are affected by the short time of water-rock interaction.The REE distributions in the yellowish fluids are also affected by very low pH(2.81 and 2.29),boiling of the fluid and precipitation of native sulfur.In the whitish fluids,adsorption by small particles and formation of REE-chloride complexes has played a role in the distribution of REE.展开更多
基金Supported in part by the Pilot Project of Knowledge Innovation Project, Chinese Academy of Sciences (Grant No.KZCX3-SW-223)the National Natural Science Foundation of China (Grant Nos. 40176020 and 40376020)
文摘Analyses of rare earth and trace element concentrations of native sulfur samples from the Kueishantao hydrothermal field were performed at the Seafloor Hydrothermal Activity Laboratory of the Key Labo-ratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences. Using an Elan DRC II ICP-MS, and combining the sulfur isotopic compositions of native sulfur samples, we studied the sources and formation of a native sulfur chimney. The results show, when comparing them with native sulfur from crater lakes and other volcanic areas, that the native sulfur content of this chimney is very high (99.96%), the rare earth element (REE) and trace element constituents of the chimney are very low (ΣREE<21×10?9), and the chondrite-normalized REE patterns of the native sulfur samples are similar to those of the Kueishantao andesite, implying that the interaction of subseafloor fluid-andesite at the Kueishantao hydrothermal field was of short duration. The sulfur isotopic compo-sitions of the native sulfur samples reveal that the sulfur of the chimney, from H2S and SO2, originated by magmatic degassing and that the REEs and trace elements are mostly from the Kueishantao ande-site and partly from seawater. Combining these results with an analysis of the thermodynamics, it is clear that from the relatively low temperature (<116 ℃ ), the oxygenated and acidic environment is favorable for formation of this native sulfur chimney in the Kueishantao hydrothermal field.
基金supported by the National Natural Science Foundation of China (40906029)the National Basic Research Program of China (2013CB429703)+1 种基金the Shandong Provincial Natural Science Foundation of China for Distinguished Young Scholars (JQ200913)the Open Fund of the Key Laboratory of Marine Geology and Environment, Chinese Academy of Sciences (MGE2011KG11)
文摘The rare earth element(REE)geochemistry of hydrothermal vent systems has been investigated intensively,but few studies have been carried out on marine shallow-water hydrothermal systems like that at Kueishantao.Here we present novel data sets of REE in hydrothermal fluids from Kueishantao,off northeastern Taiwan.The total REE(REE)concentrations of yellowish fluids are similar to those of whitish fluids,813–1212 ng/L,and are significantly higher than that of ambient seawater.The yellowish fluids have chondrite-normalized REE(REEN)distribution patterns with slight convex-downward curvatures at Eu;and the REE patterns of the whitish fluids are smooth at Eu,which is related to the lower temperature and more oxidizing conditions.The Kueishantao hydrothermal fluids are slightly enriched in light REE(La-Nd)relative to the heavy REE(Gd-Lu).The behaviors of REE in both yellowish and whitish fluids are affected by the short time of water-rock interaction.The REE distributions in the yellowish fluids are also affected by very low pH(2.81 and 2.29),boiling of the fluid and precipitation of native sulfur.In the whitish fluids,adsorption by small particles and formation of REE-chloride complexes has played a role in the distribution of REE.
