الفهرس 
Ch. 1 : IntroductionOnly 14 pages are availabe for public view
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Abstract
The present study has been carried out to clarify the geologic setting of the Gebel El-Zeit area through identification of its rock units, preparation of its stratigraphic column and delineation of its main lithology and structural elements on the geologic map by using integration of Landsat 8 data with detailed geologic field and petrographic investigations. It has also been carried out to identify the different tectonic episodes that punctuate the stratigraphic record of the Gebel El-Zeit area.
The rock types of the Gebel El-Zeit area can be broadly classified into pre-rift, syn-rift and post-rift successions. The pre-rift succession comprises the Basement rocks, the Paleozoic and the Mesozoic sedimentary rocks. The Basement Complex is made up of the Older Granitoids, Dokhan Volcanics and Younger Granites. These Basement rocks are intruded by numerous mafic – felsic dykes. The Paleozoic sequence is represented by the Cambrian clastics of the Araba and Naqus Formations. The Mesozoic deposits are represented by Cretaceous clastic and carbonate sediments. It is divisible into the Malha, Galala, Wata and Matulla Formations. The syn-rift succession comprises the Miocene Formations which are the Nukhul reefal L.S., Rudeis marls and shales, Belayim and South Gharib – Zeit evaporites. The post-rift succession comprises Pliocene to early Pleistocene calcareous sandstone, coquina limestone and mixed siliciclastic reefal limestone, Late Quaternary coral reef terraces and recent Wadi sediments.
Integration of Landsat 8 imagery processing techniques with detailed geologic field and petrographic investigations has been successfully used in geologic mapping of the Gebel El-Zeit area. FCC image (bands 7, 4, 1 in RGB) and GS Sharpen FCC image (GS Sharpen bands 7, 4, 1 in RGB) are the best transformed images which have been successfully used in delineating the different rock units as well as the major structural elements.
Morphotectonic analysis using Landsat 8 and Advanced Spaceborne Thermal Emission and Reflection Radiometer-Global Digital Elevation Model (ASTER GDEM) data of the Gebel El-Zeit area has been carried out. A (semi) automatic methodology has been applied for tectonic lineament extraction from the spectral bands of the Operational Land Imager (OLI) sensor on Landsat 8 (L8). from the ASTER GDEM data, the drainage networks have been automatically generated and the drainage basins have been automatically delineated. from the semi-automatically to fully automatically extracted morphotectonic features, the tectonic processes have been found to had a major influence on the geomorphology of the Gebel El-Zeit area. The lineaments created by recent and earlier tectonic processes have controlled, to a great extent, the alignment of Wadi Kabrit (the main valley) and the other secondary valley systems of the Gebel El-Zeit area. Major percent of all straight surface lineaments lie within a sharply defined orientation of NW-SE (parallel to the Gulf of Suez rift axis), suggesting a strong system of extensional structural fabrics that help creating the Gulf of Suez rift. By comparing the drainage lines of the Gebel El-Zeit watersheds no. 1 and 2 with the locations of major lineaments, it has been found that these drainage lines generally follow the traces of the major lineaments. Moreover, directional analysis of drainage line frequencies of these watersheds shows clusters dominated by NW-SE. This result is consistent with the major trend of the lineaments. And this consistence reveals the significance of the NW-SE oriented lineament set, which is related to the main Late Cenozoic extension occurred perpendicular to the Gulf of Suez rift axis, in controlling the geomorphology of the Gebel El-Zeit area.
Over hundred Fault-slips and other brittle structural data that can be used as kinematic indicators in paleostress analysis have been measured from a total of 18 sites within all available outcrops, which range in age from the Precambrian to the Quaternary, at the Gebel El-Zeit area. After paleostress reconstructions, 30 stress tensors have been obtained. The stress inversion results have been allowed to identify 5 different stress stages. The Basement heritage of the Gebel El-Zeit area comprises two stress stages. The first stress stage began with a period of NNW-SSE extension. The second stress stage is characterized by strike-slip regime with horizontal compression oriented NNW-SSE and horizontal extension oriented ENE-WSW. Then, during the Cambrian, the study area have been witnessed the third stress stage which is characterized by a general E-W extension. The structural fabrics imparted to the Basement during the Late Proterozoic and Cambrian appear to have played an important role in controlling the subsequent structural events. The fourth and fifth stress stages (syn-rift and post-rift stages, respectively) are related to the main Late Cenozoic extensional event. The syn-rift stage is initiated by extension occurred perpendicular to the Gulf of Suez rift axis during the Late Oligocene – Early Miocene. Then, due to both the strong fracture strength anisotropy of the Basement and the accelerated subsidence, stress permutation between stress axes (σ2/σ3 permutation) is occurred during the Early to Middle Miocene. During the Late Miocene, the tectonic subsidence and the stress permutation have diminished; marking the end of the syn-rift stage by an extension occurred perpendicular to the Gulf of Suez rift axis. The post-rift stage corresponds to the activity of the large normal faults during the Pliocene to Early Pleistocene but with small counterclockwise rotation (about 9º) of the main extension direction.