共查询到20条相似文献,搜索用时 11 毫秒
1.
Geophysical and hydrological investigations at the west bank of Nile River (Luxor, Egypt) 总被引:6,自引:5,他引:1
M. Elwaseif A. Ismail M. Abdalla M. Abdel-Rahman M. A. Hafez 《Environmental Earth Sciences》2012,67(3):911-921
Luxor, the modern Egyptian city that occupies the site of ancient Thebes, is famed for its magnificent ancient monuments. Since 1967, the Aswan high dam has prevented the annual flooding of the Nile River, resulting in excessive salt accumulation on the Nile floodplains and on exposed monument surfaces. In addition, the expansion of agricultural land within the Luxor study area has resulted in increased salinity and groundwater level. These conditions accelerate the degradation of buried and exposed monuments that were fairly well preserved in the past. To mitigate this problem, it is necessary to first understand the near-surface setting and the groundwater conditions of the Luxor area. A geophysical investigation was carried out using resistivity and electromagnetic surveys. In addition, a chemical analysis was conducted of some surface water samples collected from canals and the sacred lake of Memnon Temple. Based on the results of the geophysical surveys and the chemical analysis of the water samples, the shallow subsurface was characterized into four geoelecterical units. Groundwater flow directions were determined to be from the central area to the west, causing a rise in the groundwater levels and groundwater salinity in the area of monuments. 相似文献
2.
Ayman A. Ahmed 《Arabian Journal of Geosciences》2014,7(8):3069-3083
The occurrence of fluoride in ground water is the focus of the public and has attracted the attention of many scientists all over the world due to its importance in public health. Deficiency or increase of fluoride uptake is considered a public health problem due to the narrow permissible limit which should not exceed 1.5 mg/l according to the World Health Organization (WHO). The range of fluoride tolerance and toxicity is narrow. Deviation from the optimal levels therefore results in dental health effects such as caries and fluorosis. Many studies have found fluorosis to be invariably associated with high concentrations of fluoride in drinking water. Fluorosis is a considerable health problem in many areas of the world including Brazil, China, East Africa, Ghana, India, Kenya, Korea, Malawi, Mexico, Pakistan, South Africa, southeastern Korea, Spain, Sri Lanka, Sudan, Taiwan, Tanzania, and Turkey. Fluoride in groundwater of Quaternary aquifer of the Nile Valley, Egypt, does not gain the attention of the authors in the Nile Valley which makes the public health status of fluoride is not certain. The present work aims at investigating the fluoride concentration of Quaternary groundwater aquifer at Luxor as a representative area of the Nile Valley to be a base line for subsequent studies and criteria for public health. Ground water samples were collected from Quaternary groundwater aquifer at Luxor area, Egypt and analyzed for the purpose of investigating fluoride content. The results showed that fluoride concentration in the study area ranges between 0.113 and 0.452 with an average of 0.242 mg/l. Sources of fluoride in the study area can result from the natural dissolution from fluoride-rich minerals, fertilizers and from groundwater recharge. It is worth mentioning that low fluoride content in the study area is considered a public health threat specially limited growth, fertility, and dental caries. Corrective measures should be taken to avoid the public health impacts of fluoride deficiency at Luxor area as well as similar areas in the Nile Valley. A public health program should be initiated to account for the deficiency of fluoride in groundwater and deal with the other supplementary fluoride sources in food or fluoridation of drinking water supplies. 相似文献
3.
Hossam A. Tawfik Esam K. Zahran Abdel T. Abdel-Hameed Wataru Maejima 《Arabian Journal of Geosciences》2011,4(3-4):517-534
The widely exposed siliciclastic/carbonate succession exposed at Gebel El-Qurn, west Luxor, has been investigated from the mineralogical, petrographical and biostratigraphical points of view. The succession belongs to the lower Eocene, including the upper Esna Shale and the Thebes Formations that have been deposited under varied marine conditions and during alternating periods of abundant and ceased clastic influx. They contain abundant and well-diversified planktonic foraminifera and calcareous nannoplankton, suggesting deposition in open marine inner to middle shelf environments. Mineralogical analysis carried out by XRD revealed the presence of smectite, illite, kaolinite, sepiolite, palygorskite, and smectite–illite-mixed layer as the principal clay minerals, and calcite, dolomite, quartz, anhydrite, gypsum, hematite, and goethite as non-clay minerals. The clay mineral distributions in the sediments reflect the climatic conditions and the weathering processes at the source area as well as the differential hydraulic sorting during transportation. Calcite is the most abundant non-clay mineral, and this is consistent with high calcareous fossil content of the sediments. Petrographic examination of the carbonate lithologies within the succession enables to identify eight microfacies associations. These microfacies were affected by several diagenetic processes including; micritization, compaction, cementation, neomorphism, dissolution, dolomitization, and silicification. Dissolution of original test wall and replacement and infilling by iron oxides and recrystallized calcite were commonly observed. Calcareous nannofossils are generally common to frequent, highly diversified, and moderately to well preserved. Two calcareous nannofossil biozones; Tribrachiatus contortus Zone (NP10) and Discoaster binodosus (NP11) are recorded in the studied sediments suggesting lower Eocene age. Their associated nannofossil taxa are characterized by the predominance of warm water species. Sea-level fluctuations, basin physiography, climate, paleogeography, and sediment supply were the major controls on the deposition of the lower Eocene sediments at Gebel El-Qurn. 相似文献
4.
Hatem Odah Ahmed Ismail Ibrahim Elhemaly Neil Anderson Abbas M. Abbas Fathy Shaaban 《Arabian Journal of Geosciences》2013,6(3):865-871
The Hatshepsut Temple at Luxor, southern Egypt was built as a garden for Amun, and the first court indeed had exotic trees and vegetations. The pathway to the temple was along a sphinx-lined causeway linking the valley to pylons, which are missing now. As an effort to outline remains of the vanished garden and missing pylons and any other possible archaeological structures at this first court site, an extensive integrated magnetic/ground-penetrating radar (GPR) geophysical survey was conducted. The magnetic survey covered the entire area of the first court (100?×?60 m), while the GPR survey covered only an area of 50?×?50 m. The acquired GPR data were processed and presented as 2-D depth sections providing a reasonable vertical/horizontal resolution for the upper 6 m of the investigated site. The acquired magnetic data was processed and presented as 2-D image. The integrated interpretation of the acquired GPR and magnetic data revealed some archaeological features including a rectangular depression which is presumably an ancient man-made pond in the garden of the temple, a rectangular feature that may be a foundation of the missing pylon of the temple, and a suite of aligned anomalies that could be the remnants of sphinx. Such findings reflect the archaeological potentiality of the surveyed site and outline the extension of the temple. Meanwhile, these results necessitate further geophysical investigation or archaeological excavation to be confirmed. 相似文献
5.
Marie-Pierre Aubry William A. Berggren Christian Dupuis Holeil Ghaly David Ward Chris King Robert W. O'B. Knox Khaled Ouda Moustafa Youssef Wael Fathi Galal 《地学学报》2009,21(4):237-256
We present a review of archaeological and geological studies on the West Bank as a basis for discussing the geological setting of the tombs and geologically related problems with a view to providing archaeologists with a framework in which to conduct their investigations on the restoration, preservation and management of the antique monuments. Whereas the geology of the Upper Nile Valley appears to be deceptively simple, the lithological succession is vertically variable, and we have recognized and defined several new lithological units within the upper Esna Shale Formation. We have been able to delineate lithological (shale/limestone) contacts in several tombs and observed that the main chambers in some were excavated below the Esna Shale in the Tarawan Chalk Formation. We have been able to document changing dip in the strata (warping) in several tombs, and to delineate two major orientations of fractures in the field. Investigations behind the Temple of Hatshepsut, in the Valley of the Kings and around Deir El Medina have revealed four broad regional structures. We confirm that the hills located near the Nile Valley, such as Sheik Abdel Qurna, do not belong to the tabular structure of the Theban Mountain, but are discrete displaced blocks including the Thebes Limestone, as supported by Google Earth photographs. 相似文献
6.
In Egypt, major sustainability variables could be identified as scarce of soil and water resources, environmental degradation, rapid population growth, institutional arrangement that includes land tenure and farm fragmentation, agricultural administration, lack of infrastructure, and credit utilization. The main objective of the current work is to evaluate the sustainable land use management (SLM) model through biophysics and socioeconomic elements for the purpose of combating sustainability constraints that preclude the agricultural development geospatially. In this research, from the geomorphologic point of view, the obtained results showed three main landscapes. They were identified in the study area as: fluviolacustrine plain, Aeolian deposits, and flood plain. The study area was dominated by some physical and chemical degradation processes with different scales breaking down the equilibrium of soil stability. The SLM model was implemented and assessed from multivariate perspective points of productivity, security, protection, economic viability, and social acceptability. Four SLM classes were outlined as follows: class I, land management practices that did meet sustainability requirements with a score ≥0.65, which represented 31.0 % of the considered agricultural study area; class II, land management practices that were marginally above the sustainability threshold and represented 12.6 %; class III, land management practices that were slightly below the threshold of sustainability and represented 8.60 %; class IV, land management practices that did not meet sustainability requirements with index values >0.1 that represented 47.86 %. As a general conclusion, it is found that land management practices tend to be unsustainable in the area under investigation for certain constraints that play motivated roles in lowering the targeted land sustainability. 相似文献
7.
This study is an attempt to clarify the subsurface geological settings at Abu Darag area in the N part of the Gulf of Suez through the analysis of the available seismic data. The time contour maps of three different reflectors (Top Kareem, Within Rudeis and Top Nukhul) present in this area were constructed and several structures were detected. Generally, the area is considered as a tilted fault block dipping in NE-SW direction and it is dissected by different faults. Major and minor NW-SE faults are the strongest trend in the area while other fault trends are with very weak magnitude and limited extent. All these fault trends restrict between them some high and low areas. Also, two geo-seismic sections were built to confirm the structural prospects on Top Nukhul time contour map. 相似文献
8.
Alexandria-Nile Delta coast,Egypt: update and future projection of relative sea-level rise 总被引:1,自引:1,他引:0
Omran El Sayed Frihy Essam A. Deabes Samy M. Shereet Farid A. Abdalla 《Environmental Earth Sciences》2010,61(2):253-273
Previous studies have indicated that the Nile River deltaic plain is vulnerable to a number of aspects, including beach erosion,
inundation, and relatively high rates of land subsidence. This issue motivates an update and analysis of new tide-gauge records,
from which relative sea-level changes can be obtained. Estimated rates from five tide gauges are variable in terms of magnitude
and temporal trend of rising sea level. Analysis of historical records obtained from tide gauges at Alexandria, Rosetta, Burullus,
Damietta, and Port Said show a continuous rise in mean sea level fluctuating between 1.8 and 4.9 mm/year; the smaller rate
occurs at the Alexandria harbor, while the higher one at the Rosetta promontory. These uneven spatial and temporal trends
of the estimated relative sea-level rise (RSLR) are interpreted with reference to local geological factors. In particular,
Holocene sediment thickness, subsidence rate and tectonism are correlated with the estimated rates of relative sea-level change.
From the relatively weak correlation between them, we presume that tectonic setting and earthquakes, both recent and historical
ones, contribute more to accelerated RSLR than that of dewatering and compression/dewatering of Holocene mud underlying the
Nile Delta plain. As a result, large areas of the coastal plain have been subsided, but some sectors have been uplifted in
response to tectonic activities of thick underlying older strata. Projection of averaged sea-level rise trend reveals that
not all the coastal plain of the Nile Delta and Alexandria is vulnerable to accelerated sea-level rise at the same level due
to wide variability of the land topography, that includes low-lying areas, high-elevated coastal ridges and sand dunes, accretionary
beaches, and artificially protective structures. Interaction of all aspects (tectonic regime, topography, geomorphology, erosion
rate, and RSLR rate) permitted to define risk areas much vulnerable to impacts of sea incursion due to accelerated sea-level
rise. 相似文献
9.
Mohamed E. Hereher 《Environmental Earth Sciences》2014,72(6):1801-1809
The Lake Manzala of Egypt has a relatively short history and its future, however, is uncertain. The lake which was the biggest coastal wetland along the Mediterranean Coast is moving toward its disappearance by two opposite forces, one of them is the shrinking of the water body by siltation of sediments coming from agricultural lands and the abundance of weeds and swamp vegetation as well as the drying practices for agriculture, whereas the other force incorporates the removal of the coastal sand bar separating the lake from the Mediterranean Sea by erosion, which should eventually lead to the conversion of the lake into a coastal embayment instead of being a closed coastal lagoon. The study provided a spatiotemporal change analysis of the lake using remotely sensed data. 相似文献
10.
中国铂族元素(Platinum group elements, PGEs)矿产资源的需求量呈现不断增加的趋势, 对外依存度高达98%, 存在巨大的供应风险。从全球PGEs矿产资源的产出环境、分布特征和成因类型出发, 结合近10年全球PGEs矿产资源的开发与消费, 研判中国PGEs产业链的消费形势和供需格局, 深入分析世界和中国PGEs矿产资源的未来发展趋势, 提出保障中国PGEs资源安全供应的合理化建议, 以期实现PGEs资源的储量保障和合理配置。研究表明, ①全球PGEs资源储量稀缺, 空间分布集中, 主要分布在南非、津巴布韦、俄罗斯和北美等国家或地区, 中国探明PGEs资源量所占比重不足世界资源量的1%, 对外依存度高达98%;②全球PGEs矿床成因类型多样, 但以产于镁铁质—超镁铁质大火成岩省内的岩浆型PGEs矿床为主, 占全球PGEs矿床数量10%的大型—超大型矿床则占据了世界PGEs资源量的85%。③近3年, 全球和中国PGEs勘查工作进入低谷期, 新发现资源较少。未来10年全球供应量将不会呈现明显的增长。与此同时, 由于全球PGEs供应量主要被欧美、南非和俄罗斯等矿业寡头控制, 中国大型PGEs矿业企业国际竞争力相对较弱; ④未来10年中国PGEs需求量将高达160~185 t, 年均增长率约为2.67%, 建立战略储备、稳定全球供应和加强循环利用势在必行。 相似文献
11.
Ali Mahmoud Mahmoud Mohamed Shendi Biswajeet Pradhan Fatma Attia 《Central European Journal of Geosciences》2009,1(3):347-367
The North-Western Coast of Egypt (NWCE) represents one of the high priority regions for future development in the country. El-Hammam area is located in the NWCE with an area of 94752 acres and is one of the main challenging regions for sustaianble development. In this study, we have used remote sensing and soil data in combination with GIS tools, for land use sustainable analysis (SLU) in El-Hammam area. The SLU was established based on various factors such as: land capability and suitability, water resources availability, economic return from water and financial return from land and water. A physiographic soil map for the study area was prepared using remote sensing and GIS. Multiple field surveys were carried out for collecting information on various soil map units (SMUs) and their profiles. Laboratory analysis for the collected samples was performed, and then the soil properties were stored as attributes in a geographical soil database linked with the SMUs. Furthermore, land capability assessment was done to define the suitable areas for agricultural production using a capability model built in ALES software. Results indicate that the area currently lacks high capability and moderate capability classes. By improving the soil properties, the soil can attain potential capability; and 55630 acres will become marginally capable. The assessment of soil physical suitability for different land use types (LUTs) were analysed in ALES software, in order to generate the most suitable areas. The results from the land suitability analysis indicated that, 17114 acres are moderately suitable for wheat and sorghum; whereas 15823 acres are moderately suitable for barley and 12752 acres are moderately suitable for maize, olive and figs. Finally, the SLU was investigated based on two scenarios; (1) the most SLU under the conditions of shortage of irrigation water: clover, barley and sorghum against figs, as the irrigation requirements for barley and sorghum are low; (2) the most sustainable land use in the conditions of irrigation availability will be wheat and maize against figs and guava. From the results it is quite evident that GIS combined with modeling approaches are powerful tools for decision making in the study area. 相似文献
12.
13.
Ahmed El-Kammar 《Arabian Journal of Geosciences》2017,10(19):439
In Egypt, organic-rich sediments in the Duwi and Dakhla Formations of the Campanian-Danian age are customarily assigned as “oil shale” that occupies the middle latitudes of the country but may extend southward to Kurkur Oases. This oil shale belt has a vast worldwide extension, and it is considered as major oil- and gas-prone source rock in many places, especially in the Middle East. The sedimentation of the oil shale was triggered by the major transgression event that occurred during the Late Cretaceous. The lithology, type of kerogen, organic richness, and thickness of these organic-rich sediments vary markedly both on lateral and vertical scales. In Quseir area, the in-place geological reserves, of oil shale of the 800-kcal/kg quality, is estimated to be more than 9 billion tons that can produce 5.48 bbls equivalent upon retorting. Very optimistic resources are expected in the unexplored Nile Valley region. The factor analysis of data rank representing 1176 core samples and analysis of 58 major and trace elements besides Rock-Eval analyses point to five main controlling factors that control deposition of oil shale. The terrestrial indicators Al2O3, TiO2, Fe2O3, and K2O and the marine indicators Ca and Sr are oppositely loaded in the first factor. The second factor expresses the reducing conditions that prevailed during the deposition of the organic-rich marine environments. The euxinity of the basin is recognized by the third factor where sulfide and vanadium seem to be mutual. The fourth factor expresses the role of dolomitization while the fifth factor points to the humble role of oxidation. Considering the metric core samples, the highest TOC content recorded in the borehole drilled in Abu Tartur plateau is 3.6%, but it is about 14% for Quseir area. Regarding the spot samples in Quseir area, the highest TOC measured about 24%. It is not only the low TOC in Abu Tartur but also the kerogen type that is of type II + III, mostly of terrestrial origin (gas-prone) and lithology dominated by argillites. Organic richness is remarkable in Quseir-Safaga area, where the average TOC of 160-m-thick sequence is about 5%, with kerogen of type I or mixed I + II, mostly of marine origin (oil prone). The Dakhla Formation (Maastrichtian-Danian) is the richest in organic matter while Quseir Formation (Campanian) has the least organic richness and lowest kerogen quality. Detailed investigation on biomarkers confirms the relations among transgression, organic richness, kerogen type, and anoxic conditions. The organic matter is immature as witnessed by the low S1 values (<5%, in average), the low T max (<430 °C), the low vitrinite reflectance (<0.4%), and biomarker signature. The variation in the S1 values between 1 and 9% is attributed to the influence of tectonics associating the Red Sea rift. In Quseir-Safaga area, there are particular prolific horizons of oil shale that seem to be visible for utilization by different technologies of combustion and retorting. The content of the heavy metals and uranium, as well as the spent, is a significant benefit. The faulting, dragging, and steep tilting of beds in the Quseir-Safaga area shall remain a serious challenge for extensive utilization of the estimated in-place geological reserves. 相似文献
14.
This paper demonstrates a practical simulation approach to analyze domestic water demand and its future uncertainty in water
scarce areas through a case study of Beijing, China. Analytic models and a forecasting model were constructed using statistic
and econometric regression approaches. The analytic models were used to analyze the interrelationships between domestic water
demand and some socio-economic factors of Beijing. The forecasting model was applied to predict domestic water demand from
2009 to 2015, and this model was validated by comparing the prediction values with the observations. Scenario analysis was
applied to simulate uncertainty and risks in domestic water demand in the future. The simulation results proved that domestic
water demand will increase from 13.9×108 m3 to 16.7×108 m3 from 2009 to 2015. Three more sustainable strategies were also found through scenario analysis. The simulation and modeling
approaches and results would be very supportive for water decision makers in allocating water efficiently and making sustainable
water strategies. 相似文献
15.
Mamdouh F. Soliman Nageh A. Obaidalla Ezzat A. Ahmed Ahmed A. Ahmed Johannes Kurzweil 《Arabian Journal of Geosciences》2014,7(10):4079-4099
The Qreiya Beds that record the ‘mid-Paleocene event’ at Gabal Nezzazat occur within the Igorina albeari (P3b) Zone and constitute part of a 14-m thick shale succession that ranges in age from Early to Late Paleocene. They are composed of four alternating dark grey and brown shale beds, which are thinly laminated, phosphatic, organic-rich and extremely sulphidic. They are characterized by distinct enrichment and high peak anomalies in chalcophiles (Zn, Co, Ni, Cu and Pb) and organic association elements (V and Cr), especially within the brown organic-rich beds. It is concluded that these elements are incorporated into the phosphatic debris, sulphides and organic matter. In contrast, the grey beds are enriched in clay minerals and quartz. Clay mineral assemblages indicate alternating periods of warm/humid climate (high kaolinite) and dry climate (low kaolinite) during the formation of the grey and brown beds, respectively. The sediments of the Qreiya Beds yield lithological, biotic, geochemical and mineralogical data indicative of suboxic/anoxic marine environments as a result of high productivity and/or upwelling. The top metre of the succession below the Qreiya Beds is characterized by a progressive change from faunas dominated by praemurcurids to faunas dominated by Morozovilids, and by a progressive upward decrease in δ13Ccarb and δ18Ocarb values. The foraminiferal faunal change may reflect shallowing and warming preceding deposition of the Qreiya Beds. The change in isotopic values is inferred to be the result of surface weathering, fluvial input and diagenesis with no evidence of any primary change that could support presence of a hyperthermal event. 相似文献
16.
《Proceedings of the Geologists' Association. Geologists' Association》2023,134(2):125-138
Spyway Quarry in Dorset contains >100 tracks made by large sauropod dinosaurs walking across what was a shelly beach in the Early Cretaceous. It is the largest in situ easily accessible UK dinosaur tracksite, a unique location for the public to directly engage with dinosaurs. Following consultation on how best to open and manage the site considering its 'value', longevity, and resources available, it was left unstaffed with the track surface directly accessible. The site has been open to the elements since 2013 and to the public since 2016. We created a new photogrammetric model of the site in 2021, for comparison with an existing 2014 model to identify any changes in the trackway surface and to assess the sustainability of direct public access and weathering to the surface. To understand public use of the site, we installed a visitor counter, compiled social media reviews, and analysed photographs of visitor's movement on the quarry surface. We provide quantitative evidence for exfoliation of the track surface and reduction in the prominence of individual tracks over time primarily due to natural processes. Visitor data suggest ~10,000 people visit annually, and feedback suggests potential improvements to visitor directions and information. We do not recommend substantial changes to the site management plan given resource constraints. Our work highlights the importance of using 3D imaging techniques to document sites upon discovery and thereafter and making these data openly available to all for conservation monitoring, communication and to preserve sites' legacies. 相似文献
17.
纵观南非、埃及的水资源管理 总被引:1,自引:0,他引:1
南非地处南半球,是非洲大陆最大的国家,地处非洲大陆南端.埃及跨亚、非两洲,大部分位于非洲东北部.两国都属资源性缺水国家,两国从各自的国情出发,实行着切合实际的、严格的水资源管理政策.我国和南非、埃及有着人口多、耕地资源少、水资源紧张等相同特点,两国在水资源管理、保护和节约等方面的诸多成功经验和做法值得我国学习和借鉴. 相似文献
18.
埃及因其便利的海陆运输通道、重要的战略地位、丰富的油气资源、良好的发展前景、巨大的市场需求以及强烈的发展意愿成为我国“一带一路”倡议合作构想的理想区域。本文以埃及能源历史供需格局演变为切入点,综合预测其未来发展趋势;将埃及“2030愿景”规划与我国“一带一路”倡议及中非“十大合作计划”相结合,分析中国和埃及两国在能源及相关领域的合作机遇。得出:(1)埃及能源需求快速增长,而供应能力逐年下降,能源供需格局已由供大于求转变为供不应求,未来供需缺口将持续扩大,供需矛盾将不断加剧;(2)中埃两国合作优势互补,埃及能源及相关领域投资合作正处于良好机遇期。建议我国企业以深水地中海、西部沙漠及红海沿岸等作为重点区域开展油气勘查开发,以大开罗为中心、地中海沿岸-苏伊士运河-红海沿岸为环线开展电力及新能源、基础设施等多元化投资,将埃及打造成为我国企业进入中东-北非市场的战略支撑点。 相似文献
19.
20.
GeoJournal - Assessing land use/cover (LULC) change in coastal lakes is an essential process for sustainable development. Edku Lake is one of the most important lakes in the northern part of Nile... 相似文献