Petrographical,Mineralogical, and Geochemical Studies on Core-samples From Sidi Salim-1 Well,Nile Delta,Egypt

Abstract

Core samples of sandstone and clay raised from the Neogene succession of Sidi Salim-1 well were petrographically, mineralogically, and geochemically studied with the objective of determining the depositional conditions.

The sandstone is composed of quartz, feldspars of which the deeper sands of Qawasim Formation show some alteration; with rock fragments of volcanic, metamorphic, and sedimentary origin, in addition to altered biotite. These components are embedded in amorphous pyrite, microcrystalline calcite, and primary dolomite, as well as partial cementation by gypsum (mainly in the Pliocene sands).

The clays are composed primarily of montmorillonite, kaolinite, and illite. These clays were provided from mafic igneous rocks, sedimentary rocks, and intermediate igneous rocks, and were deposited under reducing conditions in a brackish lagoon intermittently receiving varying amounts of fresh water.     

Channel choice and the digital divide in e-government: the case of Egypt

This paper examines channel choice and the digital divide in Egyptian electronic government or e-government. Citizens have access to a variety of service delivery channels when they initiate contact with their government, ranging from e-government to more traditional channels such as the phone and in-person visits to a government office. This paper examines the extent of use of both contact channels for citizens and the impact of the digital divide on channel use. A public opinion survey of Egyptian citizens was analyzed, and the results showed that there was a digital divide in the use of e-government by citizens. The digital divide also extended to other contact channels such as the phone and when citizens used multiple contact channels for public service delivery. The results of this study imply that for the development of e-government, especially in the context of a developing country such as Egypt, policy-makers need to understand that e-government is one of many channels that citizens can use when they initiate contact with their government. The results of this study should encourage policy-makers to recognize the importance of public service delivery in a multichannel environment. Shirin Madon is the accepting Associate Editor for this article. View all notes     

GEOCHEMICAL CHARACTERIZATION OF POTENTIAL JURASSIC/CRETACEOUS SOURCE ROCKS IN THE SHUSHAN BASIN, NORTHERN WESTERN DESERT, EGYPT

Some 180 core and cuttings samples of shales and limestones from the Middle Jurassic – Late Cretaceous succession (Khatatba, Masajid, Alam El-Bueib, Alamein, Kharita, Bahariya and Abu Roash Formations) were collected from wells Ja 27–2, Tarek-1 and Jb 26–1 in the central, structurally-low part of the Shushan Basin and from well Lotus-1 in the structurally-elevated western part of the basin. All samples were screened for total organic carbon (TOC) content. Selected samples were then analyzed by Rock-Eval pyrolysis, and extracted for biomarker analyses. Visual kerogen analysis and vitrinite reflectance measurements were also undertaken and oil - source rock correlations were attempted. The results indicate that the thermal maturity of the samples can be correlated closely with burial depth. Samples from the central part of the basin are more mature than those from the west. Samples from the central part of the basin (except those from the Albian Kharita Formation) have reached thermal maturities sufficient to generate and expel crude oils. Extracts from the Middle Jurasic Khatatba and Early Cretaceous Alam El-Bueib Formations can be correlated with a crude oil sample from well Ja 27–2.
In well Lotus-1 in the west of the basin, four distinct organic facies can be recognized in the Jurassic-Cretaceous interval. One of the facies ("facies 4") has a sufficiently high TOC content to act as a source rock. Thermal maturities range from immature to peak oil generation, and the top of the oil window occurs at approximately 8000 ft.     

Reconstruction of lake-level and climate changes in Lake Qarun,Egypt, during the last 7000 years

Sediment cores from Lake Qarun provide a record of mid-late Holocene climatic changes in Northern and Eastern Africa as well as environmental changes due to the activities of ancient Egyptians. We used sedimentological, mineralogical, and geochemical analyses of the cores to investigate long-term variations in lake level due to changing hydrologic inputs. An age model based on three paired ¹⁴C and paleomagnetic measurements suggests that the base of the sediment cores is as old as ∼ 5000 B.C.E. Geochemical analyses indicated that lake sediments were derived from Nile floods with an admixture of Saharan sand. Laminated endogenic carbonate-rich clayey silt lithofacies with benthic diatoms are indicative of relatively low lake levels, saline waters and dry conditions; massive lithofacies with planktonic diatom species are indicative of relatively high lake levels, fresh waters and humid conditions. Faintly laminated clayey silt lithofacies suggest intermediate conditions. Variations in lithology as well as diatom composition suggest that the lake level has varied from relatively high levels in its early history to lower levels in later years although there have been numerous cycles in water level over the past 7000 years. A combination of climate changes in the source area of the Nile River as a result of monsoon dynamics; climatic changes in the setting area of the Lake Qarun; and human activities through the dynasties in Egypt produced these variations in lake level.     

Impact of motor vehicle exhausts on the cadmium and lead contents of clover plants grown around Egyptian traffic roads

The lead and cadmium contents of clover plants and surface soil collected from different areas adjacent to roads having various traffic densities were investigated. Results indicated that lead and cadmium contents of clover plants are highly dependent on traffic density and distance from the road. Concentrations of about 40 μg/g lead and 1.6 μg/g cadmium were found in washed clover plant samples collected from areas adjacent to the Cairo‐Alexandria Road. Washing sometimes removed more than 50 percent of plant lead content. Dust precipitated on the clover plants grown at 2 m distances from the busiest investigated road were found to contain more than 2000 μg/g lead and 40 μg/g cadmium. These concentrations decreased with the distance from the road.     

埃及与努比亚地区金字塔的联系

对埃及与南努比亚地区在地域和历史上的关联进行了分析,阐明了努比亚地区在宗教、文化和艺术等方面受埃及古王朝的影响,及其在墓葬建筑尤其是金字塔上的体现,并指出努比亚地区金字塔是该地区文化埃及化的重要象征。     

Material flow analysis and integration of watersheds and drainage systems: I. Simulation and application to ammonium management in Bahr El-Baqar drainage system

This paper is aimed at developing a systematic and generally applicable methodology for material flow analysis in drainage systems and watersheds. In particular, this research has focused on developing a mathematical framework and application for the management of nitrogenous species (primarily ammonium ions). Nitrogen compounds are among the most important species contributing to ecological cycles. Indeed, the environmental and biological aspects of water systems and their surrounding systems are highly impacted by nitrogen compounds as they contribute to the quality, nutrition, and toxicity of these systems. A material flow model was developed to deal primarily with the water phase while including pertinent information on the solid and air phases as they interface with the water medium. Both spatial and discrete temporal dimensions were included to account for nitrogen flow and transformation. The model includes the various environmental phenomena that influence the fate and transport of targeted species (e.g., volatilization, precipitation, sedimentation, uptake by biota, adsorption, chemical and biochemical reactions, etc.). Furthermore, the model includes material flow analysis operators (or transfer functions) that characterize the system inputs and outputs as they relate to the surroundings. The aforementioned material flow analysis tools were combined in a computer-aided modeling platform to provide a complete material flow analysis and yield useful insights on the transport and fate of targeted species. The simulation results shed light on the system performance. Actual data for an Egyptian drainage system (Bahr El-Baqar) along with the outfall to Lake Manzala were used to illustrate the usefulness and applicability of the developed model. Comparison with the measured data confirmed the validity and fidelity of the model.     

Time constraints set by prime contractors for their sub-contractors

The concept of pacing is described in an articulate manner which will enable readers to discuss the views put forwards. The nine major activities are divided into two types and are discussed in detail together with the methods used by the prime contractors to allocate time windows and the underlying logic employed.     

Level of chlorinated hydrocarbons in a teleost fish and a bivalve from the Egyptian Mediterranean Coast and Nile Estuary

 The residues of 22 organochlorine pollutants in fish Mugil cephalus and a bivalve Donax sp. collected from three different locations, i.e. Abu-Quir bay, Demiatta and Gamasa, were analysed by capillary GLC. The pollutants studied were 1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) isomers, cyclodiene compounds, dodecachlorooctahydro-1.3.4-metheno-2H-cyclobuto[cd]pentalene (Mirex), methoxychlor, toxaphene and hexachlorobenzene (HCB), Aroclors 1248 and 1254 as well as ten individual polychlorinated biphenyl (PCB) congeners. Extractable organic matter (EOM) levels ranged from 48.0 to 133.0 mg/g, and from 33.0 to 73.0 mg/g in bivalves and fish, respectively. 2,2-bis(p-Chlorophenyl)-1,1-dichlorethylene (p,p′-DDE) dominated other 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) analogues in fish (2.0–4.0 ng/g). 1-chloro-2,2-bis(p-chlorophenyl)ethylene (DDMU) dominated in the bivalve, its concentration ranging from 9.0 to 15.0 ng/g. The concentration of heptachlor was negligible, while endrin and dieldrin were the dominant cyclodienes, occurring in high levels in fish (0.6 and 1.3 ng/g) and bivalves (1.5 and 2.4 ng/g), at Gamasa and Demiatta, respectively. The Aroclor 1248 level was two- to threefold that of Aroclor 1254. As far as the individual PCBs are concerned, less chlorinated biphenyl congeners (from mono- to penta-chloro-biphenyls) were less concentrated except for PCB 200 and PCB 206. Toxaphene was detected at all three locations, at a maximum level of 9.7 ng/g in bivalves from Demiatta. Received: 21 October 1996 / Revised version: 27 March 1997