Comparison of activity concentration of ²³⁸U, ²³²Th and ⁴⁰K in different Layers of subsurface Structures in Dei-Dei and Kubwa, Abuja, northcentral Nigeria

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• 作者：Omeje Maxwell ; Husin Wagiran ; Noorddin Ibrahim ; Siak Kuan Lee ; Soheil Sabri
• 关键词：Geology ; Abuja ; Boreholes ; Activity concentration ; Gamma ray spectroscopy
• 刊名：Radiation Physics and Chemistry
• 出版年：2013
• 出版时间：October, 2013
• 年：2013
• 卷：91
• 期：Complete
• 页码：70-80
• 全文大小：3960 K

文摘

The study of activity concentration of ²³²Th, ²³⁸U and ⁴⁰K of rock samples from site one (S1L1-S1L11, 70 m) and site two (S2L1-S2L9, 60 m) boreholes in Dei-Dei and Kubwa was presented and the first time in the region to be compared. Activity concentrations were analysed using a high resolution co-axial HPGe gamma ray spectrometer system. The activity concentration ranges in site one borehole were from 45¡À1 to 98¡À6 Bq kg^?1 for ²³²Th, from 18¡À2 to 37¡À4 Bq kg^?1 for ²³⁸U and from 254 ¡À32 Bq kg^?1 to 1195 ¡À151 Bq kg^?1 for ⁴⁰K. The activity concentration ranges in site two borehole were from 32¡À3 to 84¡À7 Bq kg^?1 for ²³²Th, from 15¡À2 to 52¡À5 Bq kg^?1 for ²³⁸U and from 119¡À15 to 705¡À94 for ⁴⁰K Bq kg^?1. Significantly higher concentration of ²³²Th and ²³⁸U occurs in samples collected from S1L7, S1L11 and S2L1 layers. These zones experienced granitic intrusions produced by denudation and tectonism. ⁴⁰K in rock samples of S1L4 and S2L4 activity concentrations is close; it could be that biotite granitic intrusion that is inferred as the formation in that layer reflects the same activity of potassium in rock's radioactivity measurement. The area requires further investigation of soil geochemistry and activity concentration of radionuclides in groundwater.