URANIUM REMOVAL IN OCEANIC SEDIMENTS AND THE OCEANIC-U BALANCE
URANIUM REMOVAL IN OCEANIC SEDIMENTS AND THE OCEANIC-U BALANCE
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DOI：
10.1016/0012-821x(90)90101-3
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发表时间：
1990-02-01
影响因子：
5.3
通讯作者：
COCHRAN, JK
中科院分区：
文献类型：
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作者：
BARNES, CE;COCHRAN, JK
西北大西洋、卡里亚科海沟、黑海和圣克莱门特盆地的孔隙水铀数据用于计算沉积物-水界面的通量。所有样品均在现场采集，并显示孔隙水U相对于上覆水浓度的消耗。来自孔隙水梯度的铀吸收率反映了氧化还原环境，在西北大西洋的氧化/硫酸盐沉积物中，以NO3−还原为主的通量最低（10 μg/cm 2 ky），在黑海和圣克莱门特盆地的Cariaco海沟的缺氧硫酸盐还原沉积物中，通量较高（25-70 μg/cm 2 ky）。缺氧通量比较以及与以前的估计固相数据的基础上。计算表明，区域综合去除U到SUPERIONIC，半远洋沉积物是更大的幅度比缺氧，硫酸盐还原沉积物。这些通量在海洋铀平衡的背景下进行了讨论。所有海洋沉积物中U的去除估计占河流输入量的65%左右，这种汇加上蚀变洋壳中U的去除平衡了河流输入量的最可能值。
Pore water uranium data from the NW Atlantic Ocean, Cariaco Trench, Black Sea and San Clemente Basin are used to calculate fluxes across the sediment-water interface. All samples were collected in situ and show depletions in pore water U relative to the overlying water concentration. The uptake rate of U, derived from pore water gradients, reflects the redox environment, with lowest fluxes (10 μg/cm2ky) in oxic/su☐ic sediments of the NW Atlantic dominated by NO3−reduction and higher fluxes (25–70 μg/cm2ky) in the anoxic, sulfate-reducing sediments of the Cariaco Trench, Black Sea and San Clemente Basin. The anoxic fluxes compare well with previous estimates based on solid phase data. Calculations indicate that the areally integrated removal of U into su☐ic, hemipelagic sediments is of greater magnitude than that into anoxic, sulfate-reducing sediments. These fluxes are discussed in the context of the oceanic U balance. The removal of U in all oceanic sediments is estimated to account for about 65% of the riverine input, and this sink plus removal of U in altered oceanic crust balances the most probable value for riverine input.