236U, 239+240Pu and 137Cs in Gaoyou lake sediment, East China
A/Prof. Steve Tims1, Dr Yanan Huang1,2, Dr Michaela Froehlich1, Prof Shaoming Pan3, Prof Keith Fifield1, Mr Dominik Koll1,4, Dr Stefan Pavetich1, Dr Zuzana Slavkovská1, Prof Anton Wallner1,4
1Australian National University, Canberra, Australia, 2Sun Yat-sen University, , Zhuhai, China, 3Nanjing University, Nanjing, China, 4Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
The depth distributions of ²³⁶U, ²³⁹+²⁴⁰ and ¹³⁷Cs have been investigated in a Chinese freshwater lake sediment core. The 14UD accelerator at ANU was used to make AMS measurements of ²³⁶U and the plutonium isotopes, and ¹³⁷Cs was determined in the γ-ray spectrometry laboratories at Nanjing University. Pronounced peaks in the concentrations of all isotopes were identified with the 1963 peak in fallout activity. The ²³⁶U/²³⁹Pu and ²³⁹Pu/¹³⁷Cs isotopic ratios show potential for use as markers of environmental change in lake conditions over the last 60 years. Results suggest long-term artificial aquaculture may affect radionuclide accumulation in Lake Gaoyou. The core also provides a record of potential contributions from sources other than global fallout, such as the Chinese nuclear weapons test site at Lop Nor (1964-1980) or from the Chernobyl reactor incident (1986). A comparison of the new data with the limited results from other freshwater deposits will be presented.
Biography to come