Abstract Twenty rock samples (Marble, Biotite gneiss, Migmatite gneiss, Granite gneiss and Mylonites granite) were analyzed to determine the activity concentrations of 226Ra, 232Th and 40K in Bq kg−1 and their radiological parameters using gamma-ray spectrometer consisting of NaI (Tl) detector. 226Ra activity varied in the range from 7.45 ± 1.3 to 148.4 ± 15 Bq kg−1. The activity concentrations of 232Th ranged from 9.8 ± 1.6 to 432 ± 29 Bq kg−1, whereas activity concentration of 40K ranged from 519 ± 24 to 4491 ± 95 Bq kg−1. The highest average values concentration of 226Ra, 232Th and 40K were 112.1, 301 and 3875.9 Bq kg−1, respectively, which was observed in mylonites granite samples. The radiological parameters as radium-equivalent (Raeq) and external and internal hazard index (Hex, Hin) were determined. Raeq varied between 65.7 and 1147.5 Bq kg−1, which exceeded the permitted value (370 Bq kg−1) and the internal hazard index (Hin) (0.2–3.8), which is higher than 1. The total absorbed dose rates in air were calculated from the concentrations of the three radionuclides ranged from 33.2 to 521.1 nGy h−1, and the external annual effective dose rates were determined to be between 40.8 and 639.1 μSv y−1. The radiological maps of study area were obtained. The calculated average value of the radiological parameters in mylonites granite, granite gneisses and migmatite gneisses rocks samples were higher than the safe limit recommended by the Organization for Economic Cooperation and Development (OECD).

中文翻译：

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也门Hifan地区放射性参数及其与岩石类型关系的调查

摘要 对 20 块岩石样品（大理石、黑云母片麻岩、混合片麻岩、花岗岩片麻岩和糜棱岩花岗岩）进行了分析，利用由 NaI 组成的伽马射线光谱仪测定了 Bq kg−1 中 226Ra、232Th 和 40K 的活度浓度及其放射学参数（ Tl) 检测器。226Ra 活性在 7.45 ± 1.3 到 148.4 ± 15 Bq kg-1 的范围内变化。232Th 的活性浓度范围为 9.8 ± 1.6 至 432 ± 29 Bq kg-1，而 40K 的活性浓度范围为 519 ± 24 至 4491 ± 95 Bq kg-1。在糜棱岩花岗岩样品中观察到的 226Ra、232Th 和 40K 的最高平均值浓度分别为 112.1、301 和 3875.9 Bq kg-1。确定了作为镭当量 (Raeq) 和外部和内部危险指数 (Hex, Hin) 的放射学参数。Raeq 在 65.7 和 1147 之间变化。5 Bq kg-1，超过允许值 (370 Bq kg-1) 和内部危害指数 (Hin) (0.2–3.8)，高于 1。 空气中总吸收剂量率由浓度计算三种放射性核素的范围为 33.2 至 521.1 nGy h-1，外部年有效剂量率确定为 40.8 至 639.1 μSv y-1。获得了研究区的放射图。糜棱花岗岩、花岗岩片麻岩和混合片麻岩样品的放射性参数计算平均值高于经济合作与发展组织（OECD）推荐的安全限值。空气中的总吸收剂量率由三种放射性核素的浓度计算，范围为 33.2 至 521.1 nGy h-1，外部年有效剂量率确定为 40.8 至 639.1 μSv y-1。获得了研究区的放射图。糜棱花岗岩、花岗岩片麻岩和混合片麻岩样品的放射性参数计算平均值高于经济合作与发展组织（OECD）推荐的安全限值。空气中的总吸收剂量率由三种放射性核素的浓度计算，范围为 33.2 至 521.1 nGy h-1，外部年有效剂量率确定为 40.8 至 639.1 μSv y-1。获得了研究区的放射图。糜棱花岗岩、花岗片麻岩和混合片麻岩样品的放射性参数计算平均值高于经济合作与发展组织（OECD）推荐的安全限值。