ملخص: Samples of marine surface sediments of different grain sizes collected in Ghazaouet, a small bay on the western coast of Algeria, have been examined to measure [alpha]-, [beta]- and [gamma]-radioactivity. The purpose of this study is to detect any radioactive contamination. Using a combination of direct gamma spectrometry, radiochemical separation and [alpha]-spectrometry, and [beta]-counting, activity levels of the most significant naturally-occurring radioisotopes (210Po, 210Pb, 226Ra, etc.) were determined in the samples. Natural radionuclides have shown relatively high activities. The analysis of these samples revealed measurable quantities of some artificial radionuclides, namely: 238Pu (from 0.02 to 0.05Bq kg-1 ash), 239 + 240Pu (from 0.3 to 0.6Bq kg-1 ash), 137Cs (from 6.9 to 8.5Bq kg-1 ash) and 90Sr (from 1.4 to 7.4Bq kg-1 ash). Concentration ratios of 238Pu to 239 + 240Pu and 137Cs to 239 + 240Pu obtained seem to confirm that this artificial radioactivity is due mainly to nuclear-testing fallout.

لغة: إنجليزية