الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present study recorded two layers of the discoidal shape of barite concretions which penetrating the bedding plane of sandstone layers of profile four, the upper part of this concretion equivalent to fine grained sandstone where the lower part equivalent to coarse grained sandstone. The petrographic classification of sandstone samples of Wadi Halfa Oolitic Ironstone Formation according to mineral composition (quartz, lithic fragments, and feldspars) are classified as quartzarenite 66.7%, sub lithic arenite 20.9% and subarkose 12.5%. The present study adopted an intergranular pressure solution (IGV) diagram for IGV values more than 50 percent for all studied samples indicating that more of their original porosity has been destroyed cementation rather than by compaction processes for most samples.According to the results of uniaxial compressive strength test, the strength of all profiles (P1, P2, P3, P4, P5, and P6) classified as strong, very strong, strong, strong, weak and strong respectively. The highly values of compressive strength recorded in samples (P1S2, P2S1) from 97.32 to 153.71 MPa which are highly cemented by iron oxides. where the lower values of compressive strength vary from 13.64 to 28.19 MPa detected in samples (P1S1 and P5S1) which are highly weathered, highly porosity (≈ 30%), and weakly cemented by carbonates. The results of ultrasonic pulse velocity shows the average values for perpendicular and parallel are 2293 to 2340 m/sec respectively. In the applying of the strength anisotropic the average values of compressive strength of selected samples according to direction of bedding planes excluding oolitic ironstone sample (β >= 00, 450, and 900) are (74.57, 54.3, and 83.68 MPa respectively) suggested U- shape curve the maxima at 900 and 00 and minima in 450.