Page 26 - Professorial Lecture - Prof Oyedele

6.3 RESULTS

A typical set of results of average radionuclide concentrations in the soils of
the ten geographical areas to which a town is sub-divided is shown
graphically in Figure 6.4. The concentrations of the radionuclides are shown
along the vertical (or Y-axis) while the ten neighbouring geographical areas
of the town are shown along the horizontal (or X-axis). The brown open
square shows the average concentration of Uranium ( 238 U) in a given area
while the solid black square shows the average concentration of Thorium
( 232 Th) in a given area. Similarly the blue vertical bar shows the average
concentration of Potassium ( K) in a given area.
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As could be seen in the figure, the average concentrations of the three
radionuclides are not the same even in the same geographical area. Also,
for a given radionuclide, the average concentration is not the same across
the different geographical areas. Potassium ( K) has the highest average
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concentration in each of the ten areas while Uranium ( 238 U) has the lowest
average concentration in most of the areas. Thorium ( 232 Th) has an average
concentration that is a bit higher than that of Uranium in most of the areas.

These results indicate that radioactivity varies across the town and that
Potassium contributes a lot to the radioactivity in the town followed by
Thorium and Uranium.