الفهرس 
General GeologyOnly 14 pages are availabe for public view
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Abstract
North Geisum oil field is located southeast of the Zeit bay at the offshore southern part of Gulf of Suez, approximately 40 km north of Hurghada city east of Zeit bay about 8 Km. It covers an area of about 30 Km2. North Geisum oil field, is located in the northern part of the Geisum concession between Latitudes 27° 40 ` 9.3``and 27° 41` 2.157” N (554512 - 556298 N). Longitudes 33° 39` 0.59” and 33° 39` 47.9” E (876490 - 877821 E).
The present work include, seismic interpretation for the Kareem members (Shagar and Rahmi) and Rudies formations and mapping its corresponding seismic horizon over the study area. The time structure map on top of the Kareem (Shagar and Rahmi members) in the study area has revealed that the asymmetrical faulted anticline trending in a clysmic trend to NW-SE direction. The area is affected by several parallel faults. This faulting system is dissected by numerous major normal faults of different lengths, throws, widths and azimuths that forming horst and step faults. The main horst represents the less depth value around main area that increases away from this horst in all direction. Moreover, small faults are trending NE-SW ward and thrown to north. The interpreted anticline creates a structural three way closure for hydrocarbon accumulation in the study area.
This step has been followed by qualitative and quantitative well logging data interpretations (petrophysical analysis) and core analysis study for evaluating the entire sandstone of the Kareem Formation that represented by Shagar Sand, Rahmi clastics and Rahmi Sand beds within the study area.
The Upper Shagar Member consists mainly of shale, intercalated with thin limestone and minor sandstone streaks and sand body at the base called (Shagar sand bed). The Lower Rahmi Member is composed of anhydrite intercalated with shale, marl, sandstone and thick sand at the bottom (Rahmi Clastics and Rahmi sand). Rahmi and Shagar sands are deposited as submarine fans separated by marine shales and lime beds. The estimated petrophysical parameters of the reservoir throughout the study area range between about 18% and 20 % for effective porosity, 3 % and 7 % for shale volume and between 59 % and 89% for hydrocarbon saturation. The reservoir parameters of these Members (Shagar and Rahmi members) were mapped to show the lateral distribution of these parameters. The Core analysis represented by lithological description, sedimentological and petrographic facies analysis and depositional environment for the Shagar and Rahmi Members of the Kareem Formation.
The sedimentological analysis of the cored interval reveal a sequence dominated by beds of The coarse grained sandstone facies (Facies K3b) represents a distributary / braided channel deposit on the active part of a mid submarine fan lobe. The fine grained sandstone facies (Facies K3c) encountered in the Rahmi Member is interpreted as a moderate to high energy deposit on the distal margin of a mid submarine fan lobe (smooth mid fan). The underlying claystone facies (Facies K1) was deposited from suspention in a distal mid fan lobe to outer fan setting.
Also the Petrographic analysis reveals that the sandstones are mineralogical immature lithic arenites, the sandstones show variety grain sizes ranging from medium to very coarse upper grade and sorting range from poor to well sorted. All of these indicate that Kareem Sandstone beds in this field can be considered as good reservoirs with high potential for oil production.