الفهرس 
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Abstract
The aim of the study is to use the available seismic and well data to describe the stratigraphy and the structural setting of the North Ramadan field. The field is located in the southern part of Gulf of Suez. It is bounded by Morgan accommodation zone from the south. The area selected for the present detailed subsurface study has an area of about 23 Km2 and it is located in the southern part of the North Ramadan area. It is surrounded by the most prolific producing oil fields in the Gulf of Suez.
The study was accomplished through a set of seismic cross lines and in lines. The cross lines trend from the West-Southwest (WSW) to the East-Northeast (ENE). The in lines trend from South-Southeast (SSE) to North-Northwest (NNW). The KK85-1 well with its formation tops were tied to one of the seismic crosslines by a synthetic seismogram. Another two wells, NR1-AST1 and EG-2 were included for stratigraphic correlation. The construction of isochron and time-structure contour maps were performed using the Schlumberger Petrel™ software.
The stratigraphic description of the North Ramadan field was based on correlating well tops data of the three wells available. Three main stratigraphic successions were established based on the rifting stages of the Gulf of Suez. The pre-rift rock units begin with the deposition of the Jurassic to Early Cretaceous Malha Formation and ended with the deposition of the Eocene limestones. The Oligocene to Middle Miocene syn-rift rock units constitute two major groups, the Gharandal and the lower Ras Malab groups. The Gharalndal group is represented in the area by the Rudeis Formation. Three members constitute the Rudeis Formation, Mheiherrat, Hawara, and Asl. The Ras Malab has Ayun Musa, Belayim, and South Gharib formations. As for the Zeit formation, it represents the post-rift rock unit. Ayun Musa has two members, Lagia and Ras Budran. The Belayim constitutes Baba, Sidri, Feiran and Hammam Faraun. Three Isochron maps were constructed to describe the thickness of the pre-rift, and the syn-rift rock units. The thickness of the pre-rift is uniform, this was trustworthy explained by an isochron map between the top Malha and top Baba. Another isochron map describes the thickness of Hammam Faraun which thins and vanishes toward the southwest. This thinning confirms the presence of an unconformity within the syn-rift rocks. Inevitably, the seismic interpretation ratifies an onlap surface between the Miocene Hammam Faraun, and the top Baba member. To the west of the study area the syn-rift rock unit Baba member is directly overlain by the South Gharib Formation with a clear missing of the Hammam Faraun member. Another two isochron maps describe the thickness distribution of south Gharib as it gets thick toward the southwest right over the unconformity.
Three regional half-grabens, alternating in dip polarity, dominate the Gulf of Suez along its axis. In the northern half graben, the major fault blocks are southwest dipping and major faults are in the downthrown direction dipping to the to the northeast direction. In the central part of the Gulf, the structural pattern is reversed. Areas between the three major half-grabens links them together. These areas are named ‘accommodation zones’ or in other word ‘transfer zones’. The northern zone is Zaafaran, the southern is Morgan. Other terminologies were respectively used as Gharandal and Sufr el-Dara. The central part of the Gulf of Suez marks a change in fault dip polarity from the northeast dipping in the Darag basin at the north to southwest dipping in the Belayim province. On the contrary, Morgan accommodation zone marks a switch in fault dip polarity from southwest dipping at the north to the northeast dipping at the south in Amal-El Zeit province. The southern part of the Gulf of Suez has five major fault blocks based on well correlation, seismic mapping, and cross sections. These fault blocks are from southwest to northeast, Esh El Mellaha, West Zeit, East Zeit, B-Trend, and Ghara, respectively. Each one of these fault blocks is steeply tilted (30°-40°). The associated faults dips 30°-20°. These five major fault blocks in the southern part of the Gulf of Suez dominate the Miocene and Pre-Miocene rocks.
The North Ramadan field shows a half-graben structure dominated by a series of normal faults characterized by a NNW-SSE trend. Some of these faults are dipping to the ENE whereas other faults are dipping to the WSW with fault blocks tilted to the NE. The South Gharib Formation is affected by a series of three left stepping en echelon normal faults oriented NNW-SSE. This fault system has fault blocks tilted to the WSW and fault planes dip direction to the ENE. They are respectively named from the NNW to the SSE SG-1, SG-2, and SG-3. Seismic interpretation and structure contour mapping of the Hammam Faraun, and Baba members, along with the Malha Formation; shows that the three rock units are marked by one normal fault (F4) that dips to the WSW with its related block dipping to the ENE. The pre-rift rock units are represented in the area by the Malha Formation are affected by many other faults oriented NNW-SSE forming a set of horsts and grabens. Seismic mapping of Malha Formation shows seven faults named respectively from the WSW to the ENE (F1) to (F3) and (F5) to (F7). The Fault blocks are also symbolized respectively from the WSW to ENE from (B1) to (B6). The (B1) fault block is enclosed between the (F1) fault and the (F2) fault. Faults have a dip direction to the ENE. They form a half-graben that dips to the WSW. To the northeast, fault block (B2) shapes the aspects of a half-graben, that is enclosed between the (F2) fault and the (F3) fault characterized by a WSW dipping. The (F2) fault extends across the area of study. On the contrary, the (F3) fault ends to the south. The top Malha Formation is also affected by fault (F4) as Baba and Hammam Faraun members. The (F3) fault with the (F4) fault enclose a (B3) fault block. The (B3) block is tilted to the ENE forming a half-graben. The fault (F4) affects the syn-rift and the pre-rift rocks units indicating that the deposition of top Baba and Hammam Faraun members were synchronous with its displacement. A northeast fault block (B4) that dips to the WSW is enclosed between the (F4) and (F5) faults. These faults have respectively a dipping direction to the WSW and to the ENE. The (F6) and (F5) faults are sharing the (B5) fault block which dips to the WSW. A (B6) fault block is shared by the (F6) and (F7) faults. These two normal faults have different dipping attitude. The (F6) fault dips to the ENE, and the (F7) fault is characterized by a WSW dipping.
The hydrocarbon potential of the North Ramadan field was evaluated through literature review of the nearby fields in the south of the Gulf of Suez due to the lack of e-logsfor the present study. It contributes the description of the source and the reservoir rock units in the southern part of the rift basin. Source rock maturation was evaluated based on the vitrinite reflectance index and burial history diagram constructed by Lopatin (1971) and modified by Waples (1980, 1985). The burial history model was applied on some wells as GS9-1, GS173-3, Geisum W-3, and others. The maturity level of the formations penetrated by these wells was evaluated through the burial history model and the vitrinite reflectance. The Belayim Formation shows an early stage of maturation with a measured vitrinite reflectance of 0.69 percent. Kareem and Rudeis are immature in their burial history based on well GS 9-1, the maturity of these formations increases southward till reaches the gas window. Esna Formation reaches the early stages of maturation, its maturation peak is reached in well GH434-1c. Esna Formation is not present in the north part of the Gulf of Suez. It is considerably mature in the center of rift basin. Its oil or gas window are reached in some places in the south. The chalky limestone of Sudr Formation shows early stages of generation and reaches its peak maturity in the south. Matulla and Wata show an early stage of maturation in the north and show peak maturity and expulsion along with onset migration in the south. Abu Qada and Raha formations are immature; in some wells they show early maturation but in others they show oil window conditions. The Nubia ”B” is mainly composed of shale. It shows immaturity in some wells and reaches peak of maturity in few others. Nubia “B” Formation increases in maturity to the central part of the Gulf of Suez. It ranges from marginally mature to maximum maturity in the north. Its maturity increases to the south till it reaches the gas window.
The reservoir rock units in the area were evaluated throughout a qualitative and quantitative analysis in the southern part of the Gulf of Suez. Eleven wells from eleven fields were used to perform this evaluation. The Hammam Faraun member was evaluated in these wells. The lithology and saturation of this member were plotted in two wells; the M45-98, and GH 395-1 in Morgan and Ghara fields. The litho-saturation log set of the M45-98 well shows a 280 feet thickness from the Hammam Faraun member. The log is divided into three zones. The upper zone has an average porosity of 20 percent and an equal amount of matrix and clay content of 40 percent on average. The well GH395-1 in Ghara field indicates a 250 feet thickness from the Hammam Faraun member. Plot indicates an average porosity of 35 percent with no hydrocarbon saturation. The lithology indicates 45 percent sand with a thickness of 130 feet and 30 percent dolomite with a thickness of 85 feet. The clay is reflected from Kaolinite content. The shale mineral content of Hammam Faraun member is assessed using the Gamma-ray log data along with the photoelectric absorption factor (PEF) provided from wells Amal-9 and East Esh El Mellaha-2. Two cross plots were constructed to know the clay minerals in Hammam Faraun member. Clay evaluation indicates that the dominant mineralis are montmorillonite and illite with low percentage of mixed layer clay. Better reservoir quality was shown in the upper Rudeis Formation which is divided into two members, Asl and Hawara. Eleven wells were used to evaluate the reservoir quality of these two members. The quantitative analysis performed for the wells was carried out using a classical sandstone model for sand lithologies and a classical carbonate model for carbonate lithologies. The average of the petrophysical parameters of Asl and Hawara members are calculated and listed in tables. The thicknesses and the porosities of theses members, along with water and hydrocarbon saturations are listed in table too. Six wells were plotted and fully described in the thesis. Also, a new promising location was recommended to the WSW of the area based on the exploration history of the North Ramadan field along with the time-structure contour map of top Malha Formation, and the Miocene clastic isochrone map.