Direct and Indirect Effects of Uranium on Microstructure of Sedimentary Phosphate: Fission Tracks and Radon Diffusion
Moroccan sedimentary phosphates are essentially constituted by apatite and contain some tens ppm of uranium. This uranium undergoes spontaneous fission and radioactive decay in chain, since its geological formation. The spontaneous fission causes the radiation damage in the structure, by recoil of the fission products, whereas the radioactive decay products various radioactive daughters, where one of them is gas; Radon. This radioactive gas causes microstructure defects (nanopores) by diffusion. The present abstract focuses on the exam of the micro/nanostructure due to these two phenomena. The fission tracks of several grains of phosphate are studied by microscopy observations, whereas the radon emanation is analyzed by gamma spectrometry analysis of bulk of phosphate. Some interesting and correlated results are obtained.
KeywordsFission Track Spontaneous Fission Radon Activity Radon Emanation Apatite Fission Track Analysis
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