Abstract
Natural tritium production by the reaction, 63Li(n, α)31H, may in some circumstances lead to 3H contents in the fracture fluids of a granite, which are significantly above the present natural 3H content (0.5 tritium units, TU) of pre-bomb precipitation. We show here that the principal factors which determine the 3H content of the fracture fluids are the U, Th, Li and B contents of the rock and its matrix porosity. Granites with high U, Th and Li contents; low B content and a low matrix porosity may have a naturally maintained 3H content of up to about 2.5 TU in water within the matrix. This has important implications for the interpretation of groundwater flow patterns from their 3H contents. Whereas it has generally been assumed that ground-waters with 3H contents greater than 0.5 TU have a proportion of post-1954 recharge present, this may not always be a valid conclusion.
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References
Foster, S. S. D. & Smith-Carrington, A. J. Hydrol. 46, 343–364 (1980).
von Buttlar, H. & Libby, W. F. J. Inorg. nucl. Chem. 1, 75–91 (1955).
Cameron, J. F. in Radioactive Dating and Methods of Low-level Counting 543–573 (IAEA, Vienna, 1967).
Hughes, D. J. & Schwarz, R. B. Report BNL-325 (Brookhaven National Laboratory, New York, 1958).
Zito, R., Donahue, D. J., Davis, S. N., Bentley, H. W. & Fritz, P. Geophys. Res. Lett. 1, 235–238 (1980).
Parker, R. L. U.S. geol. Surv. Profess. Pap. 440–D (1967).
Feige, Y., Oltman, B. G. & Kastner, J. J. geophys. Res. 73, 3135–3142 (1968).
Hall, D. H., Black, J. H. & Storey, B. C. Rep. ENPU 81–10, (Institute of Geological Sciences, London, in the press).
Nelson, P. et al., Rep. LBL-8280 (Lawrence Berkeley Laboratory, University of California 1979).
Edmonds, E. A., McKeown, M. C. & Williams, M. British Regional Geology: South West England (Institute of Geological Sciences, London, 1975).
Burgess, W. G., Edmunds, W. M., Andrews, J. N., Kay, R. L. F. & Lee, D. J. The Origin and Circulation of Groundwater in the Carnmenellis Granite: the Hydrogeochemical Evidence (Institute of Geological Sciences, London, 1982).
Beer, K. E., Edmunds, W. M. & Hawkes, J. R. Energy 3, 281–292 (1978).
Hawkes, J. R. & Dangerfield, J. Proc. Ussher Soc. 4, 158–171 (1978).
Alderton, D. H. M., Pearce, J. A. & Potts, J. A. Earth planet. Sci. Lett. 49, 149–165 (1980).
Tammemagi, H. Y. & Wheildon, J. Geophys. J. R. astr. Soc. 38, 83–94 (1974).
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Andrews, J., Kay, R. Natural production of tritium in permeable rocks. Nature 298, 361–363 (1982). https://doi.org/10.1038/298361a0
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DOI: https://doi.org/10.1038/298361a0
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