Abdel-Azeem Marwa M, Harpy Nareman M, Alshami Abdalla S, Maadawy Wael M El
Nuclear Materials Authority, El Maadi, P.O. Box 530, Cairo, Egypt.
Sci Rep. 2024 Oct 2;14(1):22902. doi: 10.1038/s41598-024-72735-y.
Yellow ochre is the basic material used in the manufacture of yellow oxide (a commercial product). Yellow ochre samples were taken from three different formations in southwestern Sinai: Abu Hamata, Um Bogma, and Abu Zarab. Yellow ochre occasionally exists in Abu Hamata Formation particularly in El Ferah area, associated with Fe-Mn ore in Wadi El Sahu (Um Bogma Formation) and in Himayer area (Abu Zarab Formation). The XRD analysis of the raw material reveals that they are mainly composed of goethite, which is associated with quartz and kaolinite in El Ferah area, hematite, kaolinite and quartz in Himayer area, and kaolinite, gypsum and quartz in Wadi El Sahu. The commercial product is mainly composed of goethite, quartz, and calcite. The heavy mineral investigation shows that some yellow ochre samples contain zircon and rare earth sulfate which may be responsible for the radioactivity of ochre due to their thorium and uranium content. The average values of specific radio-activities of most radionuclides in the samples of Himayer area I and II, and El Sahu I are higher than the respective world averages, while their activities are lower in El Ferah and El Sahu II. Th/U and Ra/U ratios exhibit vigorous changes in physico-chemical conditions during uranium leaching and deposition. Most of the radiological parameters in the ferruginous sediment and commercial product samples from El Ferah, El Sahu II, and Himayer II are lower than the recommended international values but higher than those from Himayer I and El Sahu I samples. The plotted hierarchical cluster analysis (HCA) exhibits that the main contributors for the hazards of these sediments and their commercial product are U, Th and Ra in Himayer I &II, commercial products, and El Ferah area, Th and Ra in El Sahu II , Th, K and Ra in El Sahu I.
黄赭石是制造黄氧化物（一种商业产品）所使用的基础材料。黄赭石样本取自西奈半岛西南部的三个不同地层：阿布哈马塔、乌姆博马和阿布扎拉布。黄赭石偶尔存在于阿布哈马塔地层，特别是在费拉赫地区，与瓦迪萨胡（乌姆博马地层）和希迈尔地区（阿布扎拉布地层）的铁锰矿伴生。原材料的X射线衍射分析表明，它们主要由针铁矿组成，在费拉赫地区与石英和高岭石伴生，在希迈尔地区与赤铁矿、高岭石和石英伴生，在瓦迪萨胡与高岭石、石膏和石英伴生。该商业产品主要由针铁矿、石英和方解石组成。重矿物研究表明，一些黄赭石样本含有锆石和稀土硫酸盐，由于其钍和铀含量，可能导致赭石具有放射性。希迈尔地区I和II以及萨胡I地区样本中大多数放射性核素的比放射性平均值高于各自的世界平均值，而在费拉赫和萨胡II地区其放射性较低。钍/铀和镭/铀比值在铀浸出和沉积过程中的物理化学条件下呈现出剧烈变化。费拉赫、萨胡II和希迈尔II地区的铁质沉积物和商业产品样本中的大多数放射性参数低于国际推荐值，但高于希迈尔I和萨胡I地区样本中的参数。绘制的层次聚类分析（HCA）表明，这些沉积物及其商业产品危害的主要贡献者在希迈尔I和II地区、商业产品以及费拉赫地区是铀、钍和镭，在萨胡II地区是钍和镭，在萨胡I地区是钍、钾和镭。
