الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
The present study includes insights into the mineralogical and geochemical composition of the black shale samples of different quarries from different ages in the Beni Suef area, Egypt.
The current study is concerned generally with the black shale of Dabaa Formation at Neomeia & El Saf Quarry of Oligocene age (east Beni Suef area), Dabaa Formation at Maydoum quarry of Oligocene age (west Beni Suef area), and El Fashn Formation at Ghaiada Al-Sharqia quarry of Middle Eocene age (east Beni Suef area).
Black shale deposits are widespread in the Eocene-Miocene successions at Beni Suef area in the stable shelf of Egypt. The studied sections are located on both sides of the Nile Valley at the Beni Suef City, and we collected samples from Maydoum, Neomeia & El Saf and Ghaiada Al-Sharqia quarries. The observed rock units are, from older to younger, as follows: El Fashn of Eocene age, Dabaa Formation of Oligocene age, and Moghra Formation of Miocene age.
Several methods are mainly utilized in our study to cover the significant evaluation of black shale samples at different quarries (Maydoum, Ghaiada Al-Sharqia and Neomeia & El Saf). The analyses are XRD for mineral composition at the Faculty of Postgraduate Studies, XRF analysis at National Research Center, Egypt for major and trace elements investigation, TOC, TS, TC, Rock eval pyrolysis to determine the quantity and thermal maturation of organic matter (PY-GC) carried out at Stratochem Company to assess the chemical composition of hydrocarbon, Carbon isotopes carried out at Institute for Geology and Mineralogy in Cologne, Germany to detect the environmental and paleoclimate changes.
The result obtained from XRD analysis showed that the smectite (montmorillonite) and kaolinite are the most common clay minerals in the investigated samples, but chlorite and illite are absent. This resulted in the deposition of the collected black shale samples in shallow marine environments and detrital origin. On the other side, the major constituents are SiO2, Al2O3, TiO2, CaO, MgO, Fe2O3, K2O, P2O5, Na2O, and SO3. The trace elements measured are V, Ni, Cr, Sr, Ba, Zr, Zn, Cu, Rb, Co and Mn are investigated through XRF analysis.
Generally, the TOC value recorded 0.36 wt. % for Maydoum quarry (Dabaa Formation), reached 2.27 wt. % at Ghaiada Al-Sharqia (El Fashan Fm), and recorded 0.67 wt. % at Neomeia & El Saf (Dabaa Fm). The low value of the TOC at Maydoum quarry reflected the high oxidation of organic matter and the deposition of shale samples in shallow marine environments. The same results are observed at Neomeia & El Saf quarries. On the other side, the high value of TOC at Ghaiada Al-Sharqia reflected the high preservation of organic matter in shallow marine environments. This variation in the value of TOC is related to the different conditions of the depositional environments.
The maximum total carbon value was recorded at 8.02 wt. % at Ghaida Al-Sharqia quarry and reached 5.09 wt. % at Neomeia & El Saf quarries. These results indicated the significant content of the microfauna. On the other hand, the highest TS value reached 2.24 wt. % at Neomeia & El Saf quarries, and 1.52 wt. % at Ghaiada Al-Sharqia quarry. This indicated that these analyzed samples were mainly deposited in shallow marine environment. The low content of the total sulfur at Maydoum quarry reflected the deposition of shales in a shallow environment led to high oxidation of organic matter.
The origin of the collected shale sample was assigned by the positive relation between the TOC & TS. A similar relation was detected for the total sulfur and depositional environment, whereas the low sulfur value indicates the deposition of the shale in the oxidizing condition, but the high sulfur value of black shale refers to its deposition in a reducing environment.
The Rock-Eval pyrolysis is a responsible technique related to breaking the sample into small fragments through gradual heating under an inert atmosphere. The Rock-Eval technique is generally expressed in mg/g of sample. The results of rock eval pyrolysis reflected that the analyzed shale samples at different locations are kerogen type III of terrestrial and detrital origin that accumulated in the shallow marine environment. According to the content of the total organic carbon, S1 and S2 parameters at three quarries are poor source rock at Maydoum, Neomeia & El Saf and Ghaiada Al-Sharqia quarries.
The thermal maturation is reflected by two parameters like Tmax and (PI) obtained from Rock-Eval pyrolysis. The organic matter is in immature to early mature stage at Maydoum, Ghaiada Al-Sharqia, and Neomeia & El Saf quarries. Whereas Tmax values range from 421 to 438°C and PI values range from 0.13 to 0.42 at various quarries east and west Beni Suef area. The relationship between Tmax and HI from the studied shale samples of Dabaa and Moghra formations at Neomeia & El Saf quarries and El Fashn Formation at Ghaiada Al-Sharqia quarry are in immature to mature stage.
The relationship between TOC content and potential yield (PY), reflects that the analyzed shale samples of Dabaa and El Fashn Formation are in immature stage with poor to fair generation potential.
The PY-GC is a significant analysis used to assess the reliable type of organic compound. The results of PY-GC analysis reflected that the collected black shale samples of Dabaa, and El Fashn formations can produce natural gas of Methane (CH4), Ethane (C2H6 ) and Propane (C3H8), when they are retorted at the earth’s surface.