Pacific Ocean lead isotope

Ultraviolet spectroscopy has been applied to the determination of lead and lead speciation studies [407]. Scaule and Patterson [408] used isotope dilution-mass spectrometry to determine the lead profile in the open North Pacific Ocean. 

This simple two component model for the Fe isotope composition of seawater does not consider the effects of the Fe isotope composition of dissolved Fe from rivers or from rain. Although the dissolved Fe fluxes are small (Fig. 19) the dissolved fluxes may have an important control on the overall Fe isotope composition of the oceans if they represent an Fe source that is preferentially added to the hydrogenous Fe budget that is ultimately sequestered into Fe-Mn nodules. In particular riverine components may be very important in the Pacific Ocean where a significant amount of Fe to the oceans can be delivered from rivers that drain oceanic islands (Sholkovitz et al. 1999). An additional uncertainty lies in how Fe from particulate matter is utilized in seawater. For example, does the solubilization of Fe from aerosol particles result in a significant Fe isotope fractionation, and does Fe speciation lead to Fe isotope fractionation ... 

Christensen, J.N., Halliday, A.N., Godfrey, L.V., Hein, J.R., and Rea, D.K. (1997) Climate and ocean dynamics and the lead isotopic records in Pacific ferromanganese crusts. Science 277,913-918. 

Church S. E. and Tatsumoto M. Lead isotope relations in oceanic ridge basalts from the Juan de Fuca-Gorda ridge area, N.E. Pacific Ocean. Contr. Mineral. Petrol., 53, 1975, 253-79. 

The first neodymium-isotopic analyses aimed at characterizing the oceans closely followed the initial development of neodymium isotopes as a chronometer and tracer (Richard et al., 1976 DePaolo and Wasserburg, 1976a O Nions et al., 1977). O Nions et al. (1978) was the first to report neodymium (along with lead and strontium) isotopes in manganese nodules and hydrothermal sediments. They confirmed the distinction between continental and mantle provenances of lead in hydrogenous and hydrothermal manganese sediments, respectively. Consistent with the previous studies, they found that strontium in these deposits is derived from seawater. All of the neodymium-isotope ratios in their samples from the Pacific were similar and lower than the bulk... 

Halliday AN, Davidson JP, Holden P, DeWolf C, Lee D-C, Fitton JG (1990) Trace-element fractionation in plumes and the origin of HIMU mantle beneath the Cameroon line. Nature 347 523-528 Hamano Y, Ozima M (1978) Earth-atmosphere evolution model based on Ar isotopic data. In Alexander EC, Ozima M (eds) Terrestrial Rare Gases. Center for Academic Publications Japan, Tokyo, p 155-171 Hamelin B, Dupre B, Allegre C-J (1984) Lead-strontium isotopic variations along the East Pacific Rise and the Mid-Atlantic Ridge a comparative study. Earth Planet Sci Lett 67 340-350 Hanan BB, Graham DW (1996) Lead and helium isotope evidence from oceanic basalts for a common deep source of mantle plumes. Science 272 991-995... 

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