The Middle Miocene rocks in the northern part of the Western Desert of Egypt are dominated by carbonate rocks that constitute the Marmarica Formation. To determine the depositional environments and ...sequence architecture of the Marmarica Formation, three sections were described and sampled in detail. These sections from west to east are; Girba, Naqb El‐Migahhiz, and Gabal Umm Hiyus. The Marmarica Formation in the Siwa area includes three members, from bottom to top: the Oasis, Siwa Escarpment, and El Diffa Plateau members. The microfacies of the Marmarica Formation comprise abundant mud‐supported microfacies with minor grain‐supported microfacies. Sedimentation during the Middle Miocene took place on a homoclinal ramp. Dolomitization is the most prevalent diagenetic process that affected carbonate sediments of the Marmarica Formation. The Marmarica Formation comprises two sequence boundaries. The first sequence boundary (SB1) is demarcated by the presence of Thalassinoides ichnofacies at the boundary between the Oasis and Siwa Escarpment members in all the studied sections. It is considered a type 1 sequence boundary. The second sequence boundary (SB2) is represented by an erosional surface, which is recorded only in Girba section. The SB2 was traced at both Naqb El‐Migahhiz and Umm Hiyus sections by the occurrence of burrows that relate to the Glossifungites ichnofacies. The latter boundary is considered type 2. Three third‐order depositional sequences have been recognized in the Middle Miocene Marmarica Formation. Therefore, the Marmarica Formation at Siwa Oasis exhibits relative sea‐level oscillation. During the Middle Miocene, the prevailing warm climate caused transgression and deposition of carbonates along the marine shelf surrounding western and northern Africa.
The Middle Miocene Marmarica Formation comprises two sequence boundaries. The first sequence boundary (SB1) is determined by the presence of Thalassinoides ichnofacies at the boundary between the Oasis and Siwa Escarpment members in all the studied sections. The second sequence boundary (SB2) is represented by an erosional surface which is recorded only in Girba section. The second sequence boundary was traced at both Naqb El Migahhiz and Umm Hiyus sections by the occurrence of burrows that relate to the Glossifungites ichnofacies. Three 3rd‐order depositional sequences have been recognized in the Marmarica Formation.
In this study, Formulae were developed for rehabilitated weirs (i.e., combined weirs and orifices, weirs with 1 or 2 pipes in their bodies). Several sites of the existing rehabilitated weirs in ...El-Fayoum were visited. During the visits, measurements were undertaken (i.e., discharge, velocity, and water levels) before and after the rehabilitation of weirs. The measurements were analyzed and used as input data for model SOBEK. The model was calibrated and verified against field data. Formulae were developed from the data measurements. Moreover, two Formulae were developed, based on the model results for weirs with 1 or 2 pipes. These Formulae were validated against field measurements.
The developed weir Formulae related the parameters, defining the weir with the pipe dimensions, and the discharge. These Formulae would assist engineers in designing the modification required to develop the existing weirs in order to increase the discharge.
El-Salam Pump Stations (1) and (2) are located at 22.1km and 54.3km respectively at El-Salam Canal. When El-Salam Pump Station (1) is in operation, and switching off El-Salam Pump Station (2), water ...level rises upstream El-Salam Pump Station (2). Water level overtops El-Salam Pump Station (2) and banks upstream it. Flooding then takes place as Wadi El Noqra Canal, Egypt. This necessitates discharging the excess water to protect the pump station and the canal from water flooding when the electricity is shut down. The hydrodynamic simulation of El-Salam Canal determinates the critical time for storage capacity according to location and type of emergency spillways through the numerical model to prevent water overtopping upstream pump stations. Determination of the critical time of storage capacity is considered as a new parameter in case of the hydraulic design of the canal controlled by cross pump stations.
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