El-Wahed M.A.,Tanta University |
El-Wahed M.A.,Omar Al Mokhtar University |
Ashmawy M.,Tanta University |
Tawfik H.,Tanta University
Lithosphere | Year: 2010
We examine the evolution of the northwestern Red Sea, Egypt, by study of the Quseir-Umm Gheig subbasin. The subbasin records two main tectonic events. The first event is related to development of Late Cretaceous synclinal basins due to sinistral movement along the reactivated Najd fault system. Evidence for this includes: (1) the Cretaceous basins are concentrated mainly in the central Eastern Desert, which represents the main infiuence zone of the Najd fault system, (2) folds are not everywhere parallel to the faults and their axes are curvilinear, (3) the faults dislocated the axial plane of the synclines, (4) the Cretaceous basins occur in an en-echelon arrangement, (5) there is a difference of 20° between the orientation of the sinistral strike-slip shear zones and the associated en-echelon synclinal folds, (6) principal stress directions are delineated by subhorizontal σ1 and σ3 and subvertical σ2, (7) sheared conglomerate is detected in the Nubia Formation, (8) minor overturned folds and minor NE-vergent thrusts occur in the Duwi and Dakhla Formations, and (9) there is a predominance of NE-SW normal faults in Cretaceous-Eocene sequences. The second event is related to the sinistral movement along the NNE-SSW Aqaba-Dead Sea transform and dextral movement along Queih and Hamrawin shear zones. This movement was synchronous with northeast extension of the Red Sea. The structures developed during this movement include: (1) NW-trending extensional faults, (2) extensional fault-related folds in Miocene-Pliocene deposits, and (3) buckle folds in Pliocene and post-Pliocene sequences. Buckle folds were developed during NW compression associated with sinistral movement along NNE-SSW strike-slip faults. Gypsiferous shale-rich beds in Miocene-Pliocene rocks played the main role in development of fault-related folds and buckle folds in the Quseir-Umm Gheig subbasin. © 2010 Geological Society of America.
Amer T.M.R.,Omar Al Mokhtar University
Jamahiriya Medical Journal | Year: 2010
Natural latex from the rubber tree Hevea brasiliensis is an allergen in persons with significant cumulative latex exposure, such as those in the health care and rubber industries as well as those undergoing repeated surgeries; especially if they undergo surgeries early in life .Symptoms of latex allergy may progress rapidly and unpredictably to anaphylaxis. Since 1985, due to wide spread of human immunodeficiency virus leading to the increase in the use of latex gloves and also latex condoms, true increase in the number of persons with latex sensitivity has been noticed. Once an individual has become sensitized, he/she may experience allergic symptoms when exposed to any product containing latex. In the current case report; a known woman of latex allergy had exposed to elective cesarean section. She had developed severe anaphylactic shock and cardiac arrest during the operation. Anti-shock measures and D.C. shock therapy were done; and her heart started to beat again. After the operation had finished she was shifted to the intensive care unit to continue the management and monitoring, she stayed unconscious for five days till death. The main cause of death of this woman is the lack of knowledge about the safe measures which had to be followed in management of such cases.
El Amawy M.A.,Benha University |
Muftah A.M.,University of Benghazi |
Abd El-Wahed M.,Tanta University |
Abd El-Wahed M.,Omar Al Mokhtar University |
Nassar A.,Omar Al Mokhtar University
Arabian Journal of Geosciences | Year: 2011
Al Jabal Al Akhdar is a NE/SW- to ENE/WSWtrending mobile part in Northern Cyrenaica province and is considered a large sedimentary belt in northeast Libya. Ras Al Hilal-Al Athrun area is situated in the northern part of this belt and is covered by Upper Cretaceous-Tertiary sedimentary successions with small outcrops of Quaternary deposits. Unmappable and very restricted thin layers of Palaeocene rocks are also encountered, but still under debate whether they are formed in situ or represent allochthonous remnants of Palaeocene age. The Upper Cretaceous rocks form low-lying to unmappable exposures and occupy the core of a major WSW-plunging anticline. To the west, south, and southeast, they are flanked by highrelief Eocene, Oligocene, and Lower Miocene rocks. Detailed structural analyses indicated structural inversion during Late Cretaceous-Miocene times in response to a right lateral compressional shear. The structural pattern is themed by the development of an E-W major shear zone that confines inside a system of wrench tectonics proceeded elsewhere by transpression. The deformation within this system revealed three phases of consistent ductile and brittle structures (D1, D2, and D3) conformable with three main tectonic stages during Late Cretaceous, Eocene, and Oligocene-Early Miocene times. Quaternary deposits, however, showed at a local scale some of brittle structures accommodated with such deformation and thus reflect the continuity of wrenching post-the Miocene. D1 deformation is manifested, in Late Cretaceous, via pure wrenching to convergent wrenching and formation of common E- to ENE-plunging folds. These folds are minor, tight, overturned, upright, and recumbent. They are accompanied with WNW-ESE to E-W dextral and N-S sinistral strike-slip faults, reverse to thrust faults and pop-up or flower structures. D2 deformation initiated at the end of Lutetian (Middle Eocene) by wrenching and elsewhere transpression then enhanced by the development of minor ENE-WSW to E-W asymmetric, close, and, rarely, recumbent folds as well as rejuvenation of the Late Cretaceous strike-slip faults and formation of minor NNW-SSE normal faults. At the end of Eocene, D2 led to localization of the movement within E-W major shear zone, formation of the early stage of the WSW-plunging Ras Al Hilal major anticline, preservation of the contemporaneity (at a major scale) between the synthetic WNW-ESE to E-Wand ENE-WSW strike-slip faults and antithetic N-S strike-slip faults, and continuity of the NW-SE normal faults. D3 deformation is continued, during the Oligocene-Early Miocene, with the appearance of a spectacular feature of the major anticline and reactivation along the E-W shear zone and the preexisting faults. Estimating stress directions assumed an acted principal horizontal stress from the NNW (N33°W) direction. © Saudi Society for Geosciences 2010.
Abd El-Wahed M.A.,Tanta University |
Abd El-Wahed M.A.,Omar Al Mokhtar University |
Kamh S.Z.,Tanta University |
Kamh S.Z.,Omar Al Mokhtar University
Gondwana Research | Year: 2010
The NE-SW trending Mubarak shear belt in the Central Eastern Desert (CED) of Egypt records the structural features of a transpression regime. Structural interpretation of satellite data and field observations indicates the presence of two episodes of deformation. The less dominant D1 deformation is related to sinistral movement along NW-SE trending Wadi Abu Dabbab shear zone and formation of F1 tight to isoclinal non-cylindrical folds and thrust fan as a consequence of transpression. The thrust fan includes ESE- to SE-dipping thrusts in the ophiolitic mélange and S- to SSW-dipping thrusts in the northern part of the metagabbro-diorite complex. The transpression-related sinistral shear regime is superimposed by the dominant D2 dextral transpression along NE-SW trending Wadi El-Umra shear zone. This dextral shearing is characterized by development of NNE- to NE-trending S2 cleavage, strike-slip duplex, NNE- and NE-trending F2 folds, and NNW-directed thrusts. These two events represent a single progressive phase associated with sinistral transpressional deformation, which is related to a younger E-W shortening event. E-W directed shortening is due to oblique convergence between East and West Gondwana along the Mozambique belt. Transpressional structures in the NE-SW trending Mubarak-Barramiya shear belt indicate highly oblique convergence leading to wrench-dominated dextral transpression and development of a major flower structure between Wadi Mubarak and Hafafit dome occupying the whole width of the CED. © 2010 International Association for Gondwana Research.