Insight on Radiological Risk Assessment and its Statistical Evaluations for Abu Dabbab Albite Granite Mining Area, Central Nubian Shield, Egypt

Heikal, M.; Gomaa, S.; Monsef, Mohamed Abd El; Taha, A.A.; Top, G.; Mahmoud, K.; Mansi, M. El-

doi:10.21608/ajnsa.2018.12966

Cited by 5 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dividing line between central and southern portions of the Nubian Shield is after Stern and Hedge (1985). (b) Geological map of the Abu Dabbab area (modified after Heikal et al, 2018).…”

Section: Methodsmentioning

confidence: 99%

Geochemistry and Petrogenesis of Late Ediacaran Rare‐metal Albite Granites of the Arabian‐Nubian Shield

Amarah

Azer

Asimow

et al. 2021

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

The Abu Dabbab albite granite (ADAG), in the central Eastern Desert of Egypt, hosts the most significant rare metal ore deposit in the northern part of the Neoproterozoic Arabian-Nubian Shield. Here, we report detailed field, petrographic, mineralogical and geochemical investigation of the ADAG, an isolated stock-like granitic body with sharp intrusive contacts against metamorphic country rocks, probably emplaced at about 600 Ma. The fine-grained porphyritic upper unit is a preserved remnant of the shallowly-emplaced apex of the magma chamber, whereas the medium-grained lower unit crystallized at deeper levels under subvolcanic conditions. The peraluminous leucocratic ADAG shares common geochemical characteristics with post-collisional intraplate A-type magmas. In addition to the conspicuous enrichment in Na 2 O, the ADAG is remarkable for its anomalous concentrations of Ta, Nb, Li, Hf, Ga, Sn, Zn and heavy rare-earth elements. Nb-Ta minerals in the ADAG are mixed with Fe-Mn oxides, forming black patches that increase in abundance toward of the base of the intrusion. Columbite-tantalite, cassiterite and wolframite are the most important ore minerals. Pronounced negative Eu anomalies (Eu/Eu * = 0.10-0.24) reflect extreme magmatic fractionation and perhaps the effects of late fluid-rock interaction. The ADAG was most likely generated by partial melting of the juvenile middle crust of the ANS as the geotherm was elevated by erosional uplift following lithospheric delamination and it was emplaced at the intersection of lineations of structural weakness. Although formation of the ADAG and its primary enrichment in rare metals are essentially due to magmatic processes, late-stage metasomatism caused limited redistribution of rare metals. Fluid-driven subsolidus modification was limited to the apex of the magma chamber and drove development of greisen, amazonite, and quartz veins along fracture systems.

show abstract

Section: Methodsmentioning

confidence: 99%

Geochemistry and Petrogenesis of Late Ediacaran Rare‐metal Albite Granites of the Arabian‐Nubian Shield

Amarah

Azer

Asimow

et al. 2021

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

show abstract

“…< 1 (Table 4). suggesting the enrichment in 238 U [3,20] as well as re-mobilization in the studied rocks. This is a good agreement by [31,32].…”

Section: Correlations Of Radio-elements [ 40 K and 226 Ramentioning

confidence: 87%

“…5) indicate that, the radiometric measurement higher than chemical measurement. This attributed to huge background radiation in the studied field area, which arising from primordial radionuclides (uranium, thorium, their decay products, and potassium) as well as cosmic radiation, whereas the measured samples in the laboratory represent a small-size one; about 200 grams for each sample (Table 4 and 5) if compared with large bulk field measured point samples [19,20]. The field radiometric measurements (Table 1) and chemical determination (Table 2), tend to be equal in specific activity and concentrations for massive monzo-syenogranites samples than sheared monzo-syenogranites samples which represent the higher radioactivity concentrations of uranium and thorium if compared with massive monzo-syenogranites samples.…”

Section: Geochemistry Of Radio-elementsmentioning

confidence: 99%

Geochemical and Spectrometric Characteristics of Natural Radioactivity Levels (238-U, 232-Th, 40-K) of Monzo-Syenogranites from Wadi El-Nabi' Area, Egyptian Nubian Shield

Heikal

El-Ela

Shereif

et al. 2022

Arab Journal of Nuclear Sciences and Applications

View full text Add to dashboard Cite

Wadi El-Nabi' area (῀400km 2 ) constitutes Precambrian intrusive-extrusive complex related to the Egyptian-Nubian Shield (ENS). It includes ophiolitic serpentinites, felsic-mafic metavolcanics (bimodal metavolcanics), metapyroclastics (metatuffs), metagabbro-diorite complex, olivine gabbros, and troctolites (young gabbros), and monzo-syenogranites (younger granites). The field and lab radiometric measurements of radioelements, and their geochemical characteristics were carried out for (15) samples of monzo-syenogranites (55 km 2 ) by RS-230 γ-ray spectroscopy, and HpGe detector. Chemical analyses by ICP-MS are also obtained for the studied granitic rocks to verify the concentrations of specific elements and their inter-relationships with ( 238 U (ppm), 232 Th (ppm), and 40 K (%). Regarding the RS-230 measurements, the of radionuclide concentrations range are (4-6.6 ppm) for eU, (8.7-14.75 ppm) for eTh, and (3.62-5.15%) for K%. On the other hand, the chemical analysis for 238 U, 232 Th (ppm), and 40 K%, of monzo-syenogranites give rise to 3.04 ppm for 238 U, 9.44 ppm for 232 Th, and 1.82 % for 40 K%. The field, and lab radiometric measurements, chemical parameters of P, and D-factors ( 226 Ra/ 238 U, and Uc/Ur respectively) give rise to the disequilibrium state is well evident. On the other hand, the chemical interpretations given by multi-variation diagrams among 238 U, 232 Th, and 40 K, as well as selected elements indicate that the origin of the studied radioactive elements are related to the magmatic process, followed by the later post-magmatic process (hydrothermal).

show abstract

“…As both thorium (by adsorption) and potassium (chemical composition) are associated with clay minerals, the ratio eTh/K expresses relative potassium enrichment as an indicator of clay-mineral species and might be diagnostic of other radioactive minerals [27,28]. Therefore, if eTh/K ≥ 2 × 10 −4 , the rock is thorium-rich, and if eTh/K ≤ 1 × 10 −4 , the rock is potassium-rich [29,30]. Table 1 presents the results for the Abu Rusheid area, in which the eTh/K ratio ranged from 8.4 to 48.3, with an average value of 62.6.…”

Section: Abu Rusheid Areamentioning

confidence: 99%

Assessment of Radioactive Materials in Albite Granites from Abu Rusheid and Um Naggat, Central Eastern Desert, Egypt

et al. 2022

View full text Add to dashboard Cite

The present study aims to assess Abu Rusheid and Um Naggat albite granite’s natural radioactivity in the Central Eastern Desert, Egypt, using an HPGe laboratory spectrometer. A total of 17 albite granite samples were detected for this study. The activity concentrations were estimated for 238U (range from 204 to 1127 Bq/kg), 226Ra (range from 215 to 1300 Bq/kg), 232Th (from 130 to 1424 Bq/kg) and 40K (from 1108 to 2167 Bq/kg) for Abu Rusheid area. Furthermore 238U (range from 80 to 800 Bq/kg), 226Ra (range from 118 to 1017 Bq/kg), 232Th (from 58 to 674 Bq/kg) and 40K (from 567 to 2329 Bq/kg) for the Um Naggat area. The absorbed dose rates in the outdoor air were measured with average values of 740 nGy/h for Abu Rusheid albite granite and 429 nGy/h for Um Naggat albite granite. The activity concentration and gamma-ray exposure dose rates of the radioactive elements 238U, 226Ra, 232Th and 40K at Abu Rusheid and Um Naggat exceeded the worldwide average values that recommend the necessity of radiation protection regulation. Moreover, the corresponding outdoor annual effective dose (AEDout) was calculated to be 0.9 and 0.5 mSv y−1 for Abu Rusheid and Um Naggat albite granite, respectively, which are lower than the permissible level (1 mSv y−1). By contrast, the indoor annual effective dose (AEDin) exceeded the recommended limit (3.6 and 2.1 for Abu Rusheid and Um Naggat, respectively). Therefore, the two areas are slightly saving for development projects concerning the use of the studied rocks. The statistical analysis displays that the effects of the radiological hazard are associated with the uranium and thorium activity concentrations in Abu Rusheid and Um Naggat albite granites.

show abstract

Insight on Radiological Risk Assessment and its Statistical Evaluations for Abu Dabbab Albite Granite Mining Area, Central Nubian Shield, Egypt

Cited by 5 publications

References 0 publications

Geochemistry and Petrogenesis of Late Ediacaran Rare‐metal Albite Granites of the Arabian‐Nubian Shield

Geochemistry and Petrogenesis of Late Ediacaran Rare‐metal Albite Granites of the Arabian‐Nubian Shield

Geochemical and Spectrometric Characteristics of Natural Radioactivity Levels (238-U, 232-Th, 40-K) of Monzo-Syenogranites from Wadi El-Nabi' Area, Egyptian Nubian Shield

Assessment of Radioactive Materials in Albite Granites from Abu Rusheid and Um Naggat, Central Eastern Desert, Egypt

Contact Info

Product

Resources

About