Cs-137 Profile in Sediments in Estuaries and Its Application in Sedimentology

Pan Shaoming; Zhu Dakui; Li Yan; Xu Qigao

Six sediment cores, collected in Yangpu Harbour on Hainan Island, Out of Xiamen Harbour in Fu-jian Province and Xiangshan Harbour in Zhejiang Province, were analyzed for Cs- 137 activity, both theposition of the peak (corresponding to the period of maximum deposition) and the position of the horizon(corresponding to the first appearance of Cs- 137 in the environment)were been used to determine sedi-mentation rates.The results showed that it is possiable to use the Cs- 137 profile to determine sedimen-tation rate in estuaries, Rates for these cores based on the position of peak of Cs- 137 profile were 1.14cm /a, 1.56cm /a, 0.82cm /a, 0.75cm /a, 1.26cm /a, respectively.1.66cm /a, which are in good agreementwith that based on Pb- 210 dating and rates based on the occurrence of the horizon were larger than thatbased on Pb- 210 dating, Nhieh this indicates physical mixing or reworking of seidments in estuaryies.

1 State Pilot Laboratory of Coast & Island Exploitation,Nanjing University,Nanjing,210093;

2 Second Institute of Oceanography,State Oceanic Administration,Hangzhou,310012;

3 Department of Physics,Nanjing University,Nanjing,210093

Received Date: 1996-06-12

Publish Date: 1997-12-10

Key words:

estuary /
sedimentation rate /
Cs- 137

Abstract: Six sediment cores, collected in Yangpu Harbour on Hainan Island, Out of Xiamen Harbour in Fu-jian Province and Xiangshan Harbour in Zhejiang Province, were analyzed for Cs- 137 activity, both theposition of the peak (corresponding to the period of maximum deposition) and the position of the horizon(corresponding to the first appearance of Cs- 137 in the environment)were been used to determine sedi-mentation rates.The results showed that it is possiable to use the Cs- 137 profile to determine sedimen-tation rate in estuaries, Rates for these cores based on the position of peak of Cs- 137 profile were 1.14cm /a, 1.56cm /a, 0.82cm /a, 0.75cm /a, 1.26cm /a, respectively.1.66cm /a, which are in good agreementwith that based on Pb- 210 dating and rates based on the occurrence of the horizon were larger than thatbased on Pb- 210 dating, Nhieh this indicates physical mixing or reworking of seidments in estuaryies.

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Reference (1)

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Cs-137 Profile in Sediments in Estuaries and Its Application in Sedimentology

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