Radiometric studies of sediment cores from Gulf of Mannar
NOPR - NISCAIR Online Periodicals Repository
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Title |
Radiometric studies of sediment cores from Gulf of Mannar
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Creator |
Ray, S B
Rajagopalan, G Somayajulu, B L K |
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Description |
9-12
Gulf of Mannar sediments contain 19.2.to 61.4% CaCO3, 1.9 to 5.2 % organic matter, 7.2 to 18.8 ppm U and 3.0 to 16.7 ppm 232 Th,the last two on a calcium carbonate free basis. (234)U/(238) U activity ratio ranges from 1.09 to 1.19 (mean 1.14 ± 0.02), indicating the authigenic nature of U in the sediments. High U concentrations prevail throughout the cores (length ~ 150cm) analysed in this study. The super(14)C - based deposition rates are 60.1 and 114 cm (103 y) -1) for the shallow (water depth 1000 m) cores whereas they range from 2.2 to 11.4 cm (10 to the power of 3 y) super(-1) for the cores from the deeper (water depth> 2000m)regions. The authigenic deposition rates of U in the cores from shallow water regions are 130 and 314µg cm -2 (10 3 y)-1 during the past < 3000 y which compare well with such rates derived from anoxic coastal regions of the Atlantic and Pacific oceans. |
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Date |
2016-12-06T10:27:02Z
2016-12-06T10:27:02Z 1990-03 |
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Type |
Article
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Identifier |
0975-1033 (Online); 0379-5136 (Print)
http://nopr.niscair.res.in/handle/123456789/38177 |
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Language |
en_US
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Rights |
CC Attribution-Noncommercial-No Derivative Works 2.5 India
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Publisher |
NISCAIR-CSIR, India
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Source |
IJMS Vol.19(1) [March 1990]
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