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Geochemical characteristics of sulfide chimneys collected from arc-backarc hydrothermal fields at Western Pacific
Goldschmidt Conference Abstracts 2006
Geochemical characteristics of sulfide chimneys collected from arc-backarc hydrothermal fields at Western Pacific M. ITO1, T. NOGUCHI1, J. TAKADA2, T. OOMORI3 1
Graduate school of Engineering and Sciences, University of the Ryukyus, Japan ([email protected]; k048570@ sci.u-ryukyu.ac.jp) 2 Research Reactor Laboratory, Kyoto University, Japan (takada @HL.rri.kyoto-u.ac.jp) 3 Faculty of Science, University of the Ryukyus, Japan (oomori@ sci.u-ryukyu.ac.jp) Introduction. Chemical characteristic of poly-metallic sulfide ores formed through active submarine hydrothermal activity is generally affected by the geological setting and the interaction with the surrounding sediments. We have studied the chemical composition of hydrothermal sulfide chimneys collected from various arc and backarc hydrothermal fields of Okinawa Trough, Mariana Trough, Lau basin and Suiyo sea mount, as well as mid-ocean ridges of EPR and TAG. through dive studies by manned submersible SHINKAI2000 and SHINKAI6500. Heavy metal elements were determined by non-destructive neutron activation analysis at Kyoto University Research Reactor Laboratory. In this paper, we discuss about (1) difference between the hydrothermal fields associated with felsic magma (Okinawa Trough and Suiyo seamount) and mafic magma (mid-ocean ridges, Lau basin, and South Mariana trough), (2) influence of sediments on hydrothermal activity by comparing the two different type of hydrothermal fields; sediment hosted Okinawa Trough and few sedimented Suiyo seamount which are commonly associated with the felsic magma. Results and discussion. Sulfide chimney samples collected from the mid Okinawa Trough and Suiyo seamount revealed that contents of heavy metals (such as gold, silver, arsenic, antimony, gallium and mercury) are higher than those of sulfide chimneys collected from EPR, TAG, Lau basins and south Mariana Trough. This difference is probably due to the associated magma contents between dacite and basalt magma. Comparison of heavy metal contents of sulphide chimney between Okinawa Trough and Suiyo seamount shows similar each other except rather high antimony content in Okinawa Trough, where rather thick sediments are distributed. The differences in chemical characteristic among these hydrothermal ore deposits are reflected both the difference in the chemical composition of the magmatic hosts in hydrothermal fields resulting from plate subduction and the presence of sediments reacting with hydrothermal fields. doi:10.1016/j.gca.2006.06.569
A281
The environment isotopy and the evolution of biosphere A.A. IVANOV1, A.A. VOLKOV2 1
Institute of Geochemistry and Analytical Chemistry of Russian Academy of Science, Russia ([email protected]) 2 All Russian Federal Research Institute for Fisheries and Oceanography (VNIRO), Russia ([email protected]) There is a great deal of knowledge on biofractionation of isotopes as well as on the very nature of this phenomenon [Vernadsky-1926, Vinogradov-1957, Galimov-1981]. This report deals with evaluation of a tight link between the environment isotopy and the level of the ‘‘living substance’’ reproduction during a certain geological time intervals. In particular, one of the most massive extinctions of living organisms in entire Earth natural history had happen nearby the Perm–Trias border which corresponds to a marked change in the atmosphere isotopy towards 13C content decrease (Galimov Eric, 1981). This change mentioned had caused, presumably, by a catastrophic yield of CH4 from the World’s Ocean bottom. The isotopically light methane oxydizes into even a more isotopically light carbon dioxide with its a following photosynthesis-directed incorporation into a biosphere. This should affect the cell differentiation mechanisms requiring a definite 13C content needed for a normal DNA functioning. The cause of it could be specified as this: A new standpoint on the nature of blastomer determination is in a focus of present study. According to the concept proposed, a key initiatory role in this phenomenon belongs to the isotopy conformational effect originated during a non-equal distribution of the isotope-different nucleotide forms among a pair double-helical DNA chains. In a course of this study, a regularity of the high-ordered conformational polymorphism self-organization has been found for chemically identical blastomer DNA species in a closed (self-isolated) zygote cleavage cycle. This leads to conclusion regarding the individual distribution of the DNA genetic activity expression in blastomers which corresponds to a DNA conformational status. A mutual correspondence between experimental data and a whole concept related conclusions is now treated in the light of a cause-consequence relations to an ontogenetic nature of cell differentiation deriving it from molecular interactions conformational principle. Taking into account everything stated above, it should be logical to come up with a conclusion on either random or not a coincidence of the biosphere isotopy change and the evolution processing really was.
Reference Galimov Eric, M., 1981. The biological fractionation of isotopes. NAUKA, Moscow (in Russian). doi:10.1016/j.gca.2006.06.570
Geochemical characteristics of sulfide chimneys collected from arc-backarc hydrothermal fields at Western Pacific M. ITO1, T. NOGUCHI1, J. TAKADA2, T. OOMORI3 1
Graduate school of Engineering and Sciences, University of the Ryukyus, Japan ([email protected]; k048570@ sci.u-ryukyu.ac.jp) 2 Research Reactor Laboratory, Kyoto University, Japan (takada @HL.rri.kyoto-u.ac.jp) 3 Faculty of Science, University of the Ryukyus, Japan (oomori@ sci.u-ryukyu.ac.jp) Introduction. Chemical characteristic of poly-metallic sulfide ores formed through active submarine hydrothermal activity is generally affected by the geological setting and the interaction with the surrounding sediments. We have studied the chemical composition of hydrothermal sulfide chimneys collected from various arc and backarc hydrothermal fields of Okinawa Trough, Mariana Trough, Lau basin and Suiyo sea mount, as well as mid-ocean ridges of EPR and TAG. through dive studies by manned submersible SHINKAI2000 and SHINKAI6500. Heavy metal elements were determined by non-destructive neutron activation analysis at Kyoto University Research Reactor Laboratory. In this paper, we discuss about (1) difference between the hydrothermal fields associated with felsic magma (Okinawa Trough and Suiyo seamount) and mafic magma (mid-ocean ridges, Lau basin, and South Mariana trough), (2) influence of sediments on hydrothermal activity by comparing the two different type of hydrothermal fields; sediment hosted Okinawa Trough and few sedimented Suiyo seamount which are commonly associated with the felsic magma. Results and discussion. Sulfide chimney samples collected from the mid Okinawa Trough and Suiyo seamount revealed that contents of heavy metals (such as gold, silver, arsenic, antimony, gallium and mercury) are higher than those of sulfide chimneys collected from EPR, TAG, Lau basins and south Mariana Trough. This difference is probably due to the associated magma contents between dacite and basalt magma. Comparison of heavy metal contents of sulphide chimney between Okinawa Trough and Suiyo seamount shows similar each other except rather high antimony content in Okinawa Trough, where rather thick sediments are distributed. The differences in chemical characteristic among these hydrothermal ore deposits are reflected both the difference in the chemical composition of the magmatic hosts in hydrothermal fields resulting from plate subduction and the presence of sediments reacting with hydrothermal fields. doi:10.1016/j.gca.2006.06.569
A281
The environment isotopy and the evolution of biosphere A.A. IVANOV1, A.A. VOLKOV2 1
Institute of Geochemistry and Analytical Chemistry of Russian Academy of Science, Russia ([email protected]) 2 All Russian Federal Research Institute for Fisheries and Oceanography (VNIRO), Russia ([email protected]) There is a great deal of knowledge on biofractionation of isotopes as well as on the very nature of this phenomenon [Vernadsky-1926, Vinogradov-1957, Galimov-1981]. This report deals with evaluation of a tight link between the environment isotopy and the level of the ‘‘living substance’’ reproduction during a certain geological time intervals. In particular, one of the most massive extinctions of living organisms in entire Earth natural history had happen nearby the Perm–Trias border which corresponds to a marked change in the atmosphere isotopy towards 13C content decrease (Galimov Eric, 1981). This change mentioned had caused, presumably, by a catastrophic yield of CH4 from the World’s Ocean bottom. The isotopically light methane oxydizes into even a more isotopically light carbon dioxide with its a following photosynthesis-directed incorporation into a biosphere. This should affect the cell differentiation mechanisms requiring a definite 13C content needed for a normal DNA functioning. The cause of it could be specified as this: A new standpoint on the nature of blastomer determination is in a focus of present study. According to the concept proposed, a key initiatory role in this phenomenon belongs to the isotopy conformational effect originated during a non-equal distribution of the isotope-different nucleotide forms among a pair double-helical DNA chains. In a course of this study, a regularity of the high-ordered conformational polymorphism self-organization has been found for chemically identical blastomer DNA species in a closed (self-isolated) zygote cleavage cycle. This leads to conclusion regarding the individual distribution of the DNA genetic activity expression in blastomers which corresponds to a DNA conformational status. A mutual correspondence between experimental data and a whole concept related conclusions is now treated in the light of a cause-consequence relations to an ontogenetic nature of cell differentiation deriving it from molecular interactions conformational principle. Taking into account everything stated above, it should be logical to come up with a conclusion on either random or not a coincidence of the biosphere isotopy change and the evolution processing really was.
Reference Galimov Eric, M., 1981. The biological fractionation of isotopes. NAUKA, Moscow (in Russian). doi:10.1016/j.gca.2006.06.570