Mineralogy, geochemistry and radioactivity of some Egyptian phosphorite deposits

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1981

OSTI ID:5291148

Dabous, A A.A.

Mineralogical, geochemical, and radiogeological studies of forty-nine phosphorite samples from three main mining areas in Egypt, Abu Tartur (Western Desert), Sibaiya (Nile Valley), and Safaga (Red Sea) have been carried out. X-ray diffraction studies of these Egyptian phosphorites show that carbonate-fluorapatite (francolite) is the major phosphorite mineral in these deposits, with partial substitution of Mg and Na for Ca, and (CO/sub 3/) for (PO/sub 4/). Other minerals identified using the x-ray diffraction and scanning electron microscope include calcite, dolomite, pyrite, quartz, gypsum, feldspars, micas and clay (smectite). The uranium content and U/P/sub 2/O/sub 5/ ratio show low values in Abu Tartur phosphorite deposits relative to the Red Sea and Nile Valley deposits. Autoradiographic studies of the Egyptian phosphorites showed that the radioactivity is unequally distributed among its constituents. The opaque pellets are the most radioactive and the bone fragments are the least radioactive. Geochemically, four distinct groups of minerals were identified in the Egyptian phosphorites according to the degree of correlation between the major apatite components and the trace elements. These mineral groups are apatite, clays, heavy minerals and leached group. The results showed that the phosphorites of Nile Valley are relatively rich in Co and Zn whereas the Red Sea phosphorites are relatively rich in Pb and U. The Western Desert phosphorites are much richer in Ti as compared to the other two areas. Relative to the world phosphorites, the Egyptian phosphorites are geochemically enriched in Co, Mn, and Ni and impoverished in Sr, Cr, U, Zn, Cu, Ti, and V.

• Research Organization: Florida State Univ., Tallahassee (USA)
• OSTI ID: 5291148
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
54 ENVIRONMENTAL SCIENCES
EGYPTIAN ARAB REPUBLIC
PHOSPHORITES
GEOCHEMISTRY
MINERALOGY
RADIOACTIVITY
COBALT
LEAD
TITANIUM
URANIUM
ZINC
ACTINIDES
AFRICA
CHEMISTRY
DEVELOPING COUNTRIES
ELEMENTS
METALS
PHOSPHATE ROCKS
ROCKS
SEDIMENTARY ROCKS
TRANSITION ELEMENTS
580400* - Geochemistry- (-1989)
510301 - Environment
Terrestrial- Radioactive Materials Monitoring & Transport- Soil- (-1987)