الفهرس 
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Abstract
The economic importance of the Campanian – Maastrichtian oil shales in the Quseir –Safaga region is multiplied in the present time and is expected to grow in the near future because of the demand for energy sources as well as the providing the technology industries with rare metals. In the present thesis, the biostratigraphy of these important strata is updated according to the latest literature. In addition, a model based on organic petrography is established for the first time to explain the environmental conditions that controlled the distribution of the organic matter. Two types of localities in the Quseir –Safaga region are selected including Younis Mine and Mohamed Rabah to collect rock samples from Duwi and Dakhla formations. These rocks in Duwi and Dakhla formations are considered a suite of oil shales found in other areas in North Africa and the Middle East, which is called Parrish and Curtis (1982) upwelling belt. The organic matter quantities and composition are studied mostly by geochemical methods including the routine screen analysis by Rock-Eval, gas chromatography-mass spectrometer, and Fourier Transform Infrared (FTIR) methods. The microscopic investigations of organic matter were mostly dedicated to dinoflagellates for determining the age of these rocks. Only a few studies focused on the categorization and mode of occurrences of organic matter in these important rocks are still accumulating in the literature.) The present study aims to explore the characteristics of organic matter and to classify their organic quality in detail based on the palynofacies in addition to organic petrography in systematically collected samples from Duwi and Dakhla formation in Younis and Mohamed Rabah. The organic petrography provided fluorescence microscopy as a principal tool to test the organic quality. In addition, the study of the organic matter in the polished thin sections is used to determine the relationship between the organic matter and rock matrix and modes of organic matter occurrences. Moreover, the study aims to update the biostratigraphic zonation in these two formations by the recent works considered the dinoflagellates in Campanian –Maastrichtian rocks. The outcomes of the study are concluded in the following points:
1) The dinoflagellates represent an essential constituent of the organic matter in the Campanian Duwi Formation in both studied sections at Younis and Mohamed Rabah mines.
2) The stratigraphically important dinoflagellates are Systematophora spp., Amphorosphaeridium fenestratum, Cerodinium boloniense, Lejeunecysta hyaline, Cerodinium graulostriatum, Phelodinium cf. gaditanum, Phelodinium magnificum, Areoligera cf. senonensis, Andalusiella polymorpha, Trichodinium castanea, and Odontochitina operculata is found in the rocks of Duwi Formation.
3) The dinoflagellate assemblage in the studied section of the Duwi Formation is similar to the assemblage of Late Campanian / Early Maastrichtian I/II of Schrank and Perch – Nielsen (1985). The assemblage is characteristic of Duwi Formation in this age and is well correlated with other rocks in North Africa.
4) Another correlatable feature of the microfloral assemblage of the Duwi Formation that has been recorded in the present study is the dominant and abundant occurrences of the prasinophyte phycomata grains like Leiosphaeridia spp., Pterospermella, and Tasmanites as well as colonies of Leiosphere similar to Palambages. The chlorophytes Palambages are also common assemblages in both sections.
5) The miospores are more abundant in the lower part of the Duwi Formation and the assemblage is consisted of Cyathidites sp., Verrucatesporites sp., Clavatipollenites sp., Proxapertites cursus, Faveolatipollenites sp., Tricolpites sp., Scabrate pollen, Tricolpites reticulatus, Buttinia andreevi, Crassitricolporites brasiliensis, Liliacidites sp., and Tetrad pollens. The miospore assemblage is recorded before in Mohamed Rabah and Younis, especially in the lower part of the Duwi Formation and they mostly cross the Campanian – Maastrichtian boundary
6) The dinoflagellate assemblage in the Dakhla Formation is more diverse (39 species in the Younis section and 37 species in the Mohmed Rabah section) (Figs. 3.1 and 3.2). The most characteristic species are Palaeocystodinium australinum, Dinogymnium euclaense, Systematophora placacantha, Palaeocystodinium golzowense, Fibrocysta vectensis, Dinogymnium acuminatum, Trithyrodinium suspectum, Palaeocystodinium bulliforme, Manumiella seelandica, Lanternosphaeridium reinhardtii, Palaeocystodinium lidiae, Cannosphaeropsis utinensis, Dinogymnium longicornis, Dinogymnium kasachstanicum and Fromea fragilis.
7) This dinoflagellate assemblage is characteristic of Assemblage III (Schrank and Perch – Nielsen, 1985) and is specified with its content of diverse and abundant Dinogymnium species is characteristic for the early Maastrichtian in the Quseir-Safaga region.
8) The Leiosphaeridia spp. becomes more abundant in the Dakhla Formation, especially in the lower part of the Younis section and the upper part of the Mohamed Rabah section (Figs. 3.1 and 3.2). The other prasinophyte phycomata did not increase in the same manner in the formation although some Tasmanites grains are observed accompanying Leiosphaeridia. The chlorophytes Palambages increased also significantly (Figs. 3.1 and 3.2). The miospore assemblages did not change significantly from this recorded in the Duwi Formation Cyathidites sp., Verrucatesporites sp., Clavatipollenites sp., Rugulatispollenites sp., Faveolatipollenites sp., Tricolpites sp., Scabrate pollen, Tricolpites reticulatus, Buttinia andreevi, Spermatites sp., Liliacidites sp.. This miospore assemblage is usually characteristic of the Maastrichtian in the Quseir-Safaga region.
9) The interpretation of the paleoenvironmental conditions is based on the palynofacies and organic petrography analyses. Both tools are used to quantify and qualify the organic matter in addition to their relation to surrounding sediments. The most important environmental parameters are the proximal-distal trend that represents the relative distance from terrigenous organic matter sources. The other parameter is the oxygen depletion and it determines the preservation of the organic matter.
10) The organic matter in the Duwi Formation comprises rich marine fluorescent AOM, prasinophytes, and palynomorphs as well as minor terrigenous components.
11) The microphytoplankton-derived origin is indicated mostly in the AOM particles in the present study by inclusions of the different shapes and sizes.
12) The fluorescent AOM represents the remnant of dissolved organic matter, fecal pellets, or microphytoplankton. The microphytoplankton-derived origin is indicated mostly in the AOM particles in the present study by inclusions of the different shapes and sizes. The inclusions have diverse compositions, and they mostly include dinoflagellates, prasinophytes, and Botryococcus in addition to mineral sulfide (pyrite) specks of different densities
13) In the section perpendicular to the lamination plan, the AOM (Bituminite) is represented as stringers parallel to the lamination.
14) In Dakhla Formation, the fluorescent AOM is found to be highly mixed with Botryococcus in addition to prasinophytes and marine palynomorphs.
15) The fluorescent AOM in the Dakhla Formation is more or less similar to the AOM particles in the Duwi Formation, however, in Dakhla Formation, the AOM is brighter and has a yellow to orange color of stronger fluorescence than this in the Duwi Formation.
16) Moreover, the observed fecal pellets include many structured fine granular particles that can be of algal origin. In addition, the fluorescent AOM contains particles of sphaeromorphs that are bounded by a flack-like membrane. Furthermore, AOM includes also many prasinophyte inclusions, especially the Leiosphere.
17) In the polished rock samples, these particles are observable with a distinctive light brown in IBL and yellow color in IFL. Both the fine granular AOM and Botryococcus-like AOM (bituminite) are observed in BGM in the rock matrix. In general, Botryococcus is abundant in the Dakhla Formation and many colonies are observed in palynofacies slides. The Botryococcus thrive in the freshwater lacustrine environment and usually transfer to the basin through rivers (Tyson, 1995; Batten, 1996).
18) The prasinophyte assemblage is an essential component of the organic matter composition in the studied samples of the Duwi Formation in both of the studied sections. The prasinophytes comprise a diverse assemblage that is composed of Leiosphaeridia spp., Pterospermella, and Tasmanites and this assemblage indicates deposition during surface high paleoproductivity and stratified water columns in marine settings.
19) The prasinophytes are still abundant in the Dakhla Formation and consist of Leiosphaeridia spp. and Tasmanites. The Observation of the prasinophytes in polished rock samples revealed changes in their nature in size and color. The prasinophytes are changed to a smaller size and spherical shape in both sections. In addition, they have a darker brown color and even stronger fluorescence with orange color in both sections. Although the dinoflagellates indicate more open marine conditions, the abundant occurrences of the prasinophytes point to the occurrences of frequent blooms of microphytoplanktons during high paleoproductivity events and water column stratification low sedimentation rates in condensed sections.
20) The kerogen types are distinguished based on the area percentages of the fluorescent organic matter and the application of kerogen plots. The samples of both formations fall within oil-prone kerogen type II equivalent to hydrogen index 300-450 and >450 mg HC/g TOC.
21) The rapid sedimentation rates are indicated in the studied samples by the absence of thin lamination and occurrences of sporadic organic grains in the rock matrix as well as the scarcity of concentrated pyrite grains.
22) The thermal maturity reached immature levels in the studied sections of Duwi and Dakhla formations in the Younis and Mohamed Rabah sections. The studied sections of the Duwi and Dakhla formations contain valuable hydrogen-rich organic matter that can be treated for directed combustion in electrical power or by retorting to produce shale oil. Moreover, the heavy metals present a significant added value to the organic-rich rocks that would increase their economic value.