The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE 1,4 , while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.
Geomorphologically, the study area comprises three geomorphic units, the foreshore zone, the backshore flat and coastal sebkhas. El-Sahel (coastal) drain runs parallel to the shoreline. The coastal plain of study area is divided to northern and southern sectors; each sector covers an area of about 10Km2. The northern sector is characterized by relatively highly concentrated black sand especially the near shore area due to marine erosion and the southern sector is characterized by diluted homogenous sediments compared with the northern one.Along the shoreline of the study area, erosion and accretion phenomena are indicated by alternations of highly concentrated and low concentrated sediments, distribution of flaky, discoidal, spherical stones and mud balls. The north-western part of the northern coastal plain sector of the study area is characterized by the highly concentrated black sands extends from the fifth groin eastward about 2.5 Km. These deposits are affected greatly by a wave cut along the shore line. Rate of shoreline retreat along Abu-Khashabah beach in front of El-Matlaa Medak (road) was 43.66 m/y in the time interval between 2003 and 2012.The coastal plain of study area was covered by a total 561 collected samples at one meter depth from the surface were collected within a grid pattern 200m×200m nearly parallel and perpendicular to the shoreline. The northern sector of coastal plain area is covered by 255 samples, whereas the southern sector covered by 306 samples. Naturally highly concentrated black sands are deposited in a thin mantle near and parallel to the shoreline of the northern coastal plain sector. The highly concentrated black sands were scraped from the mantle to a depth of about 30 cm.Separation of economic heavy minerals Concentrates using physical ore dressing technique is considered closer to reality; cheap and safe method than the heavy fluid technique.The average content (Av. cont.) and reserve tonnage for each economic mineral in the studied sectors are: magnetite has an average content 11.61% with a reserve 296055 ton, ilmenite has an average content 33.74% with a reserve 860370 ton, garnet has an average content 2.88% with a reserve 73440 ton, leucoxene has an average content 2.58% with a reserve 65790 ton, zircon has an average content 4.11% with a reserve 104805 ton, rutile has an average content 1.26% with a reserve 3210 ton and monazite has an average content 0.05% with a reserve 1275 ton with a total average of economic minerals 56.23% and reserve of 1433865 tons.
Ras Baroud area has several rock units arranged from the oldest to the youngest as: older granites, younger granites, pegmatites, dykes and quartz veins. Yo u nger granite of Ras Baroud is exposed as small semirounded isolated mass, which is medium to coarse grained and pink to reddish pink in color. This granite is dissected with several types of dykes ranging from basic to acidic ones. Pegmatite body is encountered at the peripheral parts of this granite. It is compositionally zoned, being composed of massive milky quartz in the core and pink color blocky K-feldspars with subordinate nest like aggregates of yellowish white mica the outer rim. Ras Baroud granite is composed mainly of K-feldspars, plagioclase quartz and micas (biotite and muscovite) associated with zircon, titanite, and opaque as accessory minerals. On the other hand, the secondary minerals are represented by sericite and chlorite. The pegmatite bodies at the northern periphery of Gabal Ras Baroud consist essentially of orthoclase, quartz, plagioclase and mica (muscovite and biotite). The accessory minerals include zircon, allanite, fluorite and opaques. Compared to the parent granitic pluton, the pegmatite body has higher concentrations of Zr, Rb, Y, Ba, Pb, Nb and lower Cu, Sr concentrations. It is important to notice that the variation in the concentration of trace elements in the studied pegmatite samples may be due to the difference in the mineralogical composition of these samples. Uranium content in pegmatite body ranges from 10 ppm to 235 ppm with an average 84 but the thorium content range from 1 ppm to 309 ppm with an average 95. Pegmatite body of Ras Baroud has several important rare-metal bearing minerals include; samarskite-Y, columbite, cassiterite, zircon, fluorite and rutile in addition to some opaque minerals as magnetite and ilmenite.
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