Rare earths of the Nile Valley phosphorites, Upper Egypt

El-Kammar, Ahmed; Zayed, M.A.; Amer, Samar

doi:10.1016/0009-2541(79)90013-5

Cited by 22 publications

(6 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The coprolites are rounded to sub-rounded phosphatic isotropic grains, their size are ranging from silty to pebbly size and contain some quartz inclusions. Phosphorites of Duwi Formation are generally subdivided into two main categories phosphatic mudclasts and bioclasts, phosphatic mudclasts, include wellrounded to sub-rounded-spherical in shape coprolites that lack discernible internal structure and very finegrained (Baioumy and Tada, 2005), cryptocrystalline, previously collophane phosphate (Philobbos, 1964) and as ''peloids" (El-Kammar et al, 1979;El-Shazly et al, 1979;Germann et al, 1985;Glenn and Arthur, 1990). The phosphatic components are mainly bone fragments and collophane grains, the collophane grains to represent one type formed by reworking of the pre-existing chemically deposited (Philobbos (1964).…”

Section: Petrographical and Mineralogical Investigationsmentioning

confidence: 99%

See 1 more Smart Citation

Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt

Awadalla

2010

Journal of African Earth Sciences

View full text Add to dashboard Cite

Section: Petrographical and Mineralogical Investigationsmentioning

confidence: 99%

“…The francolite lattice contains around 3.2 wt.% F and 3.1 wt.% CO 2 (El Kammar and Basta, 1983). The REE content of the Nile Valley phosphorites is most probably related to the composition of the terrigenous supply of the depositional sea, rather than to its depth (El-Kammar et al, 1979).…”

Section: Geological Setting Of Abu Tartur Phosphoritesmentioning

confidence: 99%

Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt

Awadalla

2010

Journal of African Earth Sciences

View full text Add to dashboard Cite

“…The phosphatic rocks are mainly consisted of authigenic peloids and bioclasts. Peloids are considered as authigenic or reworked in origin [2,3]. The formation of phosphorites may be carried nutrients from deep water into the photic zone [4], formed in situ [5] or fluvial input [6].…”

Section: Introductionmentioning

confidence: 99%

P2O5 – F- U Characterization and Depositional Environment of Phosphatic Rocks for the Duwi Formation, Qussier- Safaga Region, Red Sea Coast, Egypt.

2019

View full text Add to dashboard Cite

T HE Duwi Formation in Qusseir-Safaga region is conformably overlain by the Qusseir variegated shales and underlain by the Dakhla shales. The studied phosphatic rocks in the Duwi Formation, is an attractive rock unit for it's enrichment in heavy metals and U content.Mineralogically, phosphatic rocks in the Duwi Formation are mainly composed mainly of fluorapatite, in addition to minor occurrence of calcite, dolomite, gypsum, quartz, and pyrite. Geochemical data reveal that the rocks of the Duwi Formation were deposited under anoxic environments. The present study used the statistical result of the interrelation between P 2 O 5 , F and U concentrations on Egyptian phosphate samples and compared to the measured data. Uranium mostly occurs in an oxidized U 6+ state. It could be fixed with the phosphatic ion, forming secondary uranium phosphate minerals such as phosphuranylite and belovite in Qusseir region. In addition to Uranyl phosphates, uranium minerals in Safaga region contain also Uranyl carbonates and Uranyl sulfates, which had been attributed to the post-depositional U enrichment. The chemical data and index show that the phosphatic rocks in Safaga region are more enriched in the majority trace and rare earth elements, and are subjected to high chemical weathering than those in Qusseir region.

show abstract

“…Phosphatic mudclasts (collophane) were described as peloids by (El-Kammar et al 1979) and occur in studied sections in sample 23 as yellow to brown colour. They are isotropic, showing spherical, oval, prismatic and irregular shapes ( Figure 5(a)).…”

Section: Phosphate Particlesmentioning

confidence: 99%

Mineralogy and ground gamma-ray spectrometric investigation for phosphates of Gabal Abu Had area, Central Eastern Desert, Egypt

Gaafar

Ghar

Ibrahim

et al. 2020

NRIAG Journal of Astronomy and Geophysics

View full text Add to dashboard Cite

The present study deals with geologic and mineralogic studies as well as gamma-ray spectrometric survey for uranium potential phosphates of Duwi Formation and environmental assessment at Gabal Abu Had environ. These phosphate deposits are considered as an important potential resource for uranium and rare earth elements as by-products. The study area lies to the NE of Qena town and dissected by Qena-Safaga asphaltic road. The Duwi Formation in the study area conformably overlies Qusseir Formation and underlies Dakhla Formation; this succession is capped with Esna and Thebes Formations and eroded along wadis which are filled with Quaternary deposits. Phosphate deposits (Duwi Formation) of Abu Had area are enriched with uranium, which may be extracted as a by-product of making fertilisers. Petrographic studies indicate that phosphate beds are composed of phosphatic particles which include collophane grains, bioclasts (bone and teeth fragments), as well as, nonphosphatic particles which include quartz, calcite and pyrite embedded in silica, calcite or iron oxides cement. XRD results showed that hydroxylapatite is the principal phosphate mineral, and the non-phosphate minerals include calcite, quartz, gypsum and anhydrite. Ground gamma-ray spectrometric results indicated that the study area has K values range from 0.2% to 4.4%, eTh values range from 0.5 to 18 ppm and eU values range from 0.5 to 100 ppm. The phosphate-bearing beds of Duwi Formation have the highest values of eU reach up to 100 ppm. The uranium anomalies mostly elongated in NW-SE trend that related to the NW-SE strike-slip faults of the area. The average value of annual effective dose rates of phosphates at Abu Had area equals 0.32 mSv/y which, less than the worldwide permissible level of annual effective dose rate (1 mSv/y).

show abstract

Rare earths of the Nile Valley phosphorites, Upper Egypt

Cited by 22 publications

References 9 publications

Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt

Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt

P2O5 – F- U Characterization and Depositional Environment of Phosphatic Rocks for the Duwi Formation, Qussier- Safaga Region, Red Sea Coast, Egypt.

Mineralogy and ground gamma-ray spectrometric investigation for phosphates of Gabal Abu Had area, Central Eastern Desert, Egypt

Contact Info

Product

Resources

About