中国渤海沉积物中铀的地球化学

GEOCHEMISTRY OF URANIUM IN SEDIMENTS OF BOHAI GULF, CHINA

The following conclusions can be drawn from the work reported in this paper: (1) Determinations were made for uranium on 16 samples by spectrophotometric method. Uranium content in the seabed sediments of the Bohal Gulf ranges from 1.6 to 6.3 ppm, with an average of 4.3 ppm. (2) Statistical data show dose relationship between U concentration:and grainsize. Relatively larger amount of uranium is accumulated in mud than in sand.The bulk of uranium is assumed to be derived from terrestrial: detrital minerals. (3) A positive correlation between U and Fe has been recognized. Similar relation can also be noticed with respect to U and Al. The plot of U concentration against Fe is linear, and can be expressed by the linear regression equation: Y=-0.37 + 1.85 X. The plot of U against Al gives an equation of Y=-2.48+1.01 X.(4)The average U/Corg.ratio for these sediments is 7×10^-4,The average ration of U/P,U/Mn,and U/CaCo3 are 100×10^-4,50×10^-4 and 2×10^-4 respectively. (5) Compared with the abundances of other shelf sediments, the average concentrations of U in the area under consideration are close to those in the shelf of Japan, the Cull of Mexico and the Black Sea. Uranium abundance in sediments from the floor of the Bohai Gulf is comparable to that of continental crust but differs from that of deep-sea clay.

The following conclusions can be drawn from the work reported in this paper:(1) Determinations were made for uranium 011 16 samples by spectrophotome-tric method. Uranium content in the seabed sediments of the Bohai Gulf ranges from 1.6 to 6.3 ppm, with an average of 4.3 ppm.(2) Statistical data show close relationship between U concentration and grain size. Relatively larger amount of uranium is accumulated in mud than in sand. The bulk of uranium is assumed to be derived from terrestrial detrital minerals.(3) A positive correlation between U and Fe has been recognized. Similar re-lation can also be noticed with respect to U and Al. The plot of U concentration against Fe is linear, and can be expressed by the linear regression equation: Y = -0.37 + 1.35X. The plot of U against Al gives an equation of Y = -2.48 + 1.01 X.(4) The average U/Corg. ratio for these sediments is 7 × 10-4, The average ra-tios of U/P, U/Mn, and U/Ca.CO3 are 100 × 10-4 50 × 10-4 and 2 × 10-4 respective-ly.(5) Compared with the abundances of other shelf sediments, the average con-centrations of U in the area under consideration are close to those in the .shelf of Japan, the Culf of Mexico and the Black Sea. Uranium abundance in sediments from the floor of the Bohai Gulf is comparable to that of continental crust but dif-fers from that of deep-sea clay.