A study on redox sensitive elements in the sediments at dredged trenches in Tokyo Bay by instrumental neutron activation analysis

Research paper by T. Yamagata, K. Shozugawa, R. Okumura, K. Takamiya, M. Matsuo

Indexed on: 31 Aug '14Published on: 31 Aug '14Published in: Journal of Radioanalytical and Nuclear Chemistry


To evaluate redox conditions at dredged trenches in Tokyo Bay, the concentrations of U, Th, Ce, Fe, and Mn in sediments were measured. In the Th/U–Ce/U plots, the values of Th/U and Ce/U ratios at each site gathered in different places on a same line. Therefore, it is considered that Th/U and Ce/U ratios are reflecting the redox states in different sites. The concentrations of Fe and Mn in August 2011 decreased near the surface at dredged trenches. It is presumed that their concentrations at dredged trenches are influenced by the redox conditions of the surface of sediments.