الفهرس 
Chapter one : Location and Previous workOnly 14 pages are availabe for public view
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Abstract
The Belayim Land Oil Field is located within PETROBEL development leases in the eastern coast of the Gulf of Suez, Egypt between longitudes 33˚12̀ and 33˚15̀ east and latitudes 28˚35̀ and 28˚40̀ north. Belayim Land Oil Field was discovered at the beginning of 1954. The average production rate recorded was 75000BOPD.
The sedimentary stratigraphic sequence of Belayim Land Oil Field is represented by sediments deposited from Precambrian to Quaternary. The high quality reservoir rocks have been deposited during Miocene time. Belayim Formation of Belayim Land Oil Field is divided into four members, named from bottom to top: Baba, Sidri, Feiran and Hammam Faraun members. The present study focuses on the reservoir properties and evaluation of Sidri Member.
Sidri Member underlies anhydrite beds of Feiran Member and overlies evaporite intercalated with thin beds of shales of Baba Member of Belayim Formation. It varies in total facies thickness of the subsurface section from 9m to 117m. It consists of a thick body of medium grained, moderately oil saturated sandstone intercalated with silty shales. These sediments were deposited in Mid-late Serravallian (Middle Miocene) sediments.
Sidri Member is the most important productive oil reservoir zone for Belayim Formation of Belayim Land Oil Field in the Gulf of Suez region. This zone may produce about 30% from the total production of the field.
The current seismic interpretation of Belayim Land Oil Field highlighted the general structural configuration. This field consists of NNW–SSE trending anticline about 10Km long and 4km wide. This anticline is cutting two main faulting systems. The faulting systems are parallel to the coast, related to Gulf of Suez rift (Westward is dipping); and borders the investigated oil field cutting through the lower Miocene until post Miocene sediments. This represents a normal step faulting system of NNW–SSE parallel to Suez graben trend. The second is NNE-SSW trend represented by a series of transcurrent faults which tend to subdivide the structure into several sectors.
Sidri Member is represented by sand, sandstone and shale with average net pay thickness ranges from 5 to 60m. The sandstone is classified into sub litharenites, lithic arkose and arkose microfacies. These microfacies are composed of quartz, feldspars, rock fragments and some glauconitic grains are embedded in calcareous or evaporitic cement. The siliciclastic grains are sub angular to sub rounded closely packed grains with straight and concavo-convex contacts and well to moderately sort. These grains range from fine sand to granule size with small clay lenses. In the studied Sidri sandstone the visual porosity from point count range from 5% to more than 20%.
The sedimentary structures are represented by horizontal lamination and planner cross bedding. Feldspars are altered to clay minerals and some grains are leached later giving rise to secondary porosity. The pore spaces are partially to completely fill by clay minerals, dolomite and evaporite cements. Modal analysis study shows that Sidri sandstone components have been almostl originated and accumulated from older basement rocks.
The studied sandstones were affected by several diagenetic processes such as dissolution, compaction, cementation and clay authigensis. The Major diagenetic processes that preserves or enhances porosity is dissolution. Dissolution in Sidri sandstones primarily exhibited as dissolution of carbonate and feldspar cement. Most of the secondary porosity may be resulted from the partial to complete dissolution of carbonate cement. Dehydration of clay minerals may also accelerate dissolution. Dissolution of detrital feldspar grains is observed as porosity generated within and on the outer surface of the feldspar grains.
On the other hand, the Major diagenetic processes that destroy porosity include compaction and cementation. Compaction is a suite of mechanical and chemical processes resulting in the collapse of pore spaces in sandstone. The evidence of mechanical compaction long (line contact) - and concavo-convex contacts. Cementation include three types of cement were recorded in the Sidri sandstone such as carbonate cement, quartz overgrowth and anhydrite cement. Carbonates cement is represented by dolomite and calcite cements, which are generally the most significant authigenic constituent in Sidri sandstone. Quartz overgrowth is precipitated around the quartz grains. Silica might be generated from the migration of silica rich solution and/or the alteration of feldspathic grains into kaolinite. Anhydrite cement might be produced from the precipitation of the evaporitic pore water under great depth of the studied sequence. Clay authigensis are volumetrically small but important components for Sidri sandstones because of the enormous effect on permeability. It is represented by kaolinite which may be formed from alteration of feldspars.