الفهرس 
Objective, approach and activities conductedOnly 14 pages are availabe for public view
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Abstract
The objectives of this thesis is to investigate the sources of recharge, renewability, fossil water contribution and salinity evolution of the groundwater resources in the western zones of Maghagha , ElMinia Governorate , Upper Egypt. These are important attributes for sustainable development of water resources. A complementary approach has been used to achieve the objectives of this work, this combines (in an integrative term) the hydrochemical and isotopic techniques with the hydrogeological investigation. The results of study are presented in three chapters as follow:
Chapter One: Introduction and Background Information
This chapter contains a general description of the problem under study, the motivation for its conduct, the objective and activities conducted to achieve it. A brief description of the study area, literature review of the previous work conducted on the subjects of the study and a background information about the hydrochemical and isotopic techniques used in the thesis, have been given in the chapter.
Chapter Two: Techniques and Methodologies
This chapter describes the techniques and methodologies applied for field work, lab analysis and office activities. It described the sampling procedures, measurement techniques and the tools used for data treatment, processing, analysis, interrelation and interpretation.
Chapter Three: Results and Discussion.
This chapter dealt with the following three major topics:
1-Geological and Hydrogeological characterizations
Three geomorphologic units appear in the study area , from east to west (young alluvial plain, old alluvial plain and plateau) . The young alluvial plain bounds the Nile River and is filled with Holocene silt and clay, it is followed westward by the old alluvial plain unit and desert fringes (which is covered by Pleistocene sands and gravels) and the lower Eocene Plateau unit. The study area is characterized by a lithostratigraphic succession dominated by Eocene limestone rock units related to three formations Maghagha, Samallut, and El Minia.. The post-Eocene rocks include: (1) Oligocene sands and gravels which are exposed in the west and northwestern part of the study area, (2) Pliocene dark clays and undifferentiated sands, (3) Pleistocene alluvial deposits (sand, gravel with clay lenses), (4) Holocene Nile silt and clay Hydrogeologically, two main aquifers are encountered in the area under study and surroundings namely the Quaternary (alluvium) aquifer and the Eocene limestone aquifer. In addition to these aquifers, the deep Nubian sandstone aquifer which underlain the whole western desert, it contains paleowater of no recent recharge, its high pressure in a presence of joints and fractures gets it pass to the upper aquifers.
2-Recharge Sources, Renewability and Fossil Water Contribution
The results of isotopic analysis (Oxygen -18, Deuterium and Tritium and Carbon-14) of the collected samples have been used to infer the rechargability and renewability. The groundwater of the Quaternary aquifer is renewable and gets whole recharge from Nile system, it is connected with Eocene aquifer which gets its recharge from two sources: - the present day Nile water and the paleowater of fossil origin that upward leaks through joints and fractures from the deep seated Nubian sandstone aquifer. The relative contribution of the paleowater increases westward (ranges between 26 and 100 %) and becomes dominant and solely exists at about 40 km westward, the groundwater is renewable to the east and renewability decreases westward. The radiocarbon dating indicates that the paleowater in the study area has a C14 age equal 10120 ybp , the samples that get a mixed recharge of Nubian sandstone paleowater with present day Nile water has C14 ages less than 10120 ybp in proportion to the mixing ratio.
4- Hydrochemical characteristics and Salinity Evolution
The results of analysis of major ions (TDS, Na+, K+, Ca2+, Mg2+, Cl-, HCO3– and SO42- ) for 43 groundwater samples have been treated, processed and analyzed using Statistical Techniques, GIS methodology, Standards Graphs and Cross Plots, Softwares (eg SPSS, Solminique, …) . The data of the chemical analysis of the collected samples have been used for identifying the chemical characteristics and salinization processes of the groundwater under study and for evaluating the hazards of its use for drinking and irrigation.
The variability coefficients have been calculated of the TDS and major ions concentration, these show significantly high values reflecting a less homogeneity or heterogeneity in salinization and recharge processes of the two aquifers. The TDS values of the analyzed samples range between 7987.3 mg/l and 786.35 mg/l with 16.28 % in the fresh and 83.72 % in brackish water. The ranges of TDS and major ions of the Quaternary samples are two to four folds higher than that of Eocene ones. About 25% of the Quaternary samples occupies the excess range space beyond that of Eocene. This reflects the presence of a local zone with local conditions causing these higher salinity values, this zone has been delineated in the northeastern zone of the study, it is affected by poor drainage and water logging that activate salts concentration by evaporation, leaching and drainage discharge).
The areal distribution of TDS shows an increase from south to north in the Quaternary and Eocene aquifers with parallel increase of shale and clay content. The TDS of Eocene aquifer also increases westward where carbonates and saline water leakage from deep aquifer dominate, away from Quaternary aquifer.
Multivariate analysis of the groundwater data set under study was performed through the Correlation Coefficient Matrix (CCM), hierarchical cluster analysis (HCA) and Principal Components Analysis (PCA) techniques using SPSS.22 software. Eight hydrochemical variables (TDS, Na+, K+, Ca2+, Mg2+, Cl–, HCO3– and SO42-) for a set of 43 samples were used in the multivariate analyses in this study.
The Correlation Coefficients (shows that TDS is strongly associated with Cl–, Na+, Mg2+, Ca2+, and SO4 ionic species The ionic pairs of high C.C. are Na-Cl & Mg – Cl & Mg- SO4 & Ca – SO4 & Ca – Cl , the salts of these ionic pairs could control the groundwater salinity.
The hierarchical cluster analysis (HCA) is used for Comparisons based on multiple parameters from different samples which were grouped and classified according to their similarity and the output results are presented in the form of a dendogram. The grouping of the samples complies with variation and distribution of TDS and ionic composition, which are controlled by hydrogeochemical and physicochemical conditions
The Principal Components Analysis (PCA) reduced the large data set with underlying linear structures into two Principal Components, without sacrificing much of the original information,. , the first principle component ( PC -1), accounts for 72.028% of the variance in the data set and combines the chemical variables TDS, Cl-, Na+, Mg2+, Ca2+ and inversely combines pH and HCO3- , the second component (PC -2) represents about 10.9% of the variance and combines HCO3- and pH as a major factors. The 1.st component express the variability affected by rock/water interaction processes and mixing of water of different origins, The 2.nd component expresses the effects of salts precipitation under high pH alkaline conditions.
Three water types and nine ionic orders were defined for the study samples The 1.st water type is Cl-Na represents 60.46 % of the samples, with ionic orders characterizing an advanced stage of mineralization and potential salinization processes (dissolution, weathering and ion exchange on lithofacies contact). The 2.nd and 3.rd water types are SO4 - Ca and SO4 – Na , respectively represent about 16.27% and 16.27% of the samples , their ionic orders reflect the increase of SO42- with Ca2+ and Na+ content which may be attributed to leakage and drainage water of agriculture land in addition to the carbonate dissolution.
The hypothetical salts combinations have been determined for the study samples. The determined salt combinations and the percentage of their occurrence in the study samples group are indicated. The salt combination agrees with the hydrochemical facies and agree with salinity evolution
The distribution of the samples on Piper Diagram reflects the domination of (SO42- + Cl- /Na++K+) and (SO42- +Cl- /Ca2+ + Mg2+) hydrochemical facies of high salinity evolution stage in about 80% of the samples, the rest of samples reflects less developed salinity stage which has higher HCO3- content than the dominating one.
The salinization processes that could contribute to salt composition of the collected groundwater samples have been examined using Saturation Indexes (SI) and Standard Cross Plots (Na+ vs Cl- ) & (Ca2++Mg2+) vs (HCO3- +SO42- ) & (Na+ + Cl-) vs total cations & (Ca2+ + Mg2+ – SO4 2- + HCO3-) vs (Na+ - Cl- ), The distribution of the samples on each of the indicated plots and diagrams was used to test the role of a specific salinization processes on the chemical composition of the study samples. It has been indicated that the major salinization processes in the study area are: halite and carbonates dissolution, cation exchange as well as mixing the less saline recent recharge with saline paleowater of deep origin.
The results of major ions (TDS, Na+, K+, Ca2+, Mg2+, Cl–, HCO3– and SO42- ) and trace elements (Fe3+, Cd2+, Co2+, Cr3+, Cu2+, Mn2+, Ni2+, Pb2+, Al3+ , Mo2+ , V5+ , Si4+ ) analysis of the collected groundwater samples have been used to evaluate the quality hazards of using the groundwater under study for irrigation and drinking purposes and the suitability for that. This has been conducted by comparing the concentration of ions in the samples with the safe limits recommended for these uses, in the international reference standards, also by calculating number of indexes based on ions concentration either separate or integrative collective. About half of the samples are excellent to good for irrigation use and half are poor need management. The irrigation suitability of the study groundwater increases eastward toward flood plains away from carbonates table land. About 35% of the samples are excellent to good for drinking and the rest are of lower grade (dominating in the northeastern zone is of lowest grade).