الفهرس 
CHAPTER 1Only 14 pages are availabe for public view
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Abstract
The total area of Nile Delta is 26,450 Km2 of which 19, 200 Km2 inland and 7,250 Km2 offshore. The Nile Delta is locate sedimentary build up began in the Miocene time with a very thick section of Late Tertiary – Quaternary sediments indicating a rapid and continuous deposition in a gradually subsiding basin. This section consists mainly of shale with sandstone intercalations.
The study area is located approximately 120km NE of Alexandria, which lies offshore in the deep water (250-1500m) of the present day Nile Delta lies between latitude 32º 16` & 32º 06`N and longitudes 30º 44` & 30º 56`E, Simian is one of the major channel systems that make up the Mid-Pliocene submarine channel complex mapped in the West Delta Deep marine concession. It has two distinct branches that merge to the north, with numerous, meandering channels mapped within each
The materials used in this study include collection and description of core samples and core analysis from wells, as well as the complete log sets from ten wells in the study area, including the composite, Gamma Ray (GR), Spontaneous Potential (SP), Caliper, Deep and Shallow Laterolog resistivities (LLD, LLS), Micro-Spherically Focused log (MSFL), Photoelectric factor (PEF), and porosity tools (Density, Neutron, and Sonic), In the form of (LAS Format). A review of the available previous geological and geophysical studies as well as internal reports of oil companies is helpful to study the general,
TechLog computer programs for the quantitative estimations of the subsurface sequence have been used; Also Perel Software has beed used for mapping purpous.
Reviews of the available previous geological and geophysical studies as well as internal reports of oil companies are helpful to study the general stratigraphic column of the Nile Delta with special emphasis on the study field.
The Simian field was discovered by the Simian-1 well in 1999. The field is locating at the east of WDDM concession (east to Scarab-Saffron, Serpent and Sapphire discoveries and slightly west of and shallower than Sienna discovery)
Stratigraphic column of the Nile Delta is ranging in age from Mezozoic to recent, Is represented by the Tineh Formation of Late Oligocene/Early Miocene, which consists of very thick series of marine to fluvio-marine shale and sandstone interbeds, The Qantara Formation has been dated as Early Miocene,. It is equivalent to the Moghra Formation in the Western Desert. The formation is delineated overlying the Tineh/Dabaa formations (Late Oligocene) and underlying the Sidi Salim Formation. The Qantara Formation is made up of calcareous shale with sandstone and limestone streaks that deposited in a variety of coastal littoral to inner sub-littoral environment and it may rank to a coastal lagoonal one, The Qawasim Formation Tortonian – Messinian in age forms an angular unconformity over the Sidi Salim Formation. Early Miocene represented by the Abu Madi Formation, Early to Late Pliocene is represented by the Kafr El Sheikh Formation that started with the deposition of the Early Pliocene sediments during marine flooding, The Late Pliocene to Early Pleistocene is represented by El Wastani Formation that was deposited as a regressive sequence after a starvation event of the Kafr El Sheikh Formation, The Late Pliocene to Early Pleistocene is represented by El Wastani Formation that was deposited as a regressive sequence after a starvation event of the Kafr El Sheikh Formation and Pleistocene – Holocene Age is represented by; the Mit Ghamr and Bilqas formations.
Simian channel lies at the base of the El Wastani Formation at a similar level to the many slope channels laying in the same play in the offshore Nile Delta area,Simian is a combination stratigraphic/structural feature with dip-closure along the northern and southern margins and stratigraphic closure (channel margin pinch-out) along the whole length of the reservoir. El Wastani Formation claystones form the seal to the Simian field. The Simian field comprises a number of deep marine channels constrained within a NNE-SSW trending initial channel valley cut. There are two main branches to Simian, which merge to the north where the maximum width of the field is over 5 km without including the western sheet like high amplitude area, which is supposed to be either sheet sand or laterally amalgamated channel sand.
The Nile delta sub divided into two sub provinces by a faulted hinge line oriented WNW to ESE allocated at Kafr El Sheikh Latitude city. This hinge line is known as the faulted flexure that is separates the south delta province from the north delta plain basin, this hinge is the most significant structural feature of the Nile Delta region and is known as the faulted flexure. It separates the Southern ridge from the Northern Delta basin. The different structural trends are East- Northeast of Late Cretaceous to Eocene age and those Syrian arc folds
The Nile cone is a recent phenomenon when compared with other major deltas, The Nile Delta can be subdivided into the following structural sedimentary provinces (A) The South Delta province, a continuation of Western Desert stratigraphic sequences and structure, The North Delta basin, The Nile cone and The Levant platform.
This third Chapter presents the results of the structural and sedimentological interpretation of a Schlumberger FMI (Fullbore Formation MicroImager) and conventional core data from wells Simian-1 and Simian-2 in Simian Field, also the integration this data with the available seismic data to build a depositional model representing the studied area.
from the Core and the FMI correlation the wells include a range of depositional facies that are consistent with a deep marine setting. They include six facies: 1- Cross-stratified sandstones which form a c. 25 cm thick set of coarse-grained sands close to the base of a sand package that is interpreted as a channel-fill. Their occurrence near the base of interpreted channel-fill sequences is indicative of bypass prior to channel-filling. 2- Massive sandstones witch represented by thick to very thick-bedded massive medium to coarse-grained sandstones with abundant clasts and larger rafts of shale, interpreted as debris flow deposits, 3- Normally graded sandstone to mudstone witch repreneted by Medium to thick-bedded, fine to coarse-grained non-amalgamated sandstones occur as a relatively abundant facies. Both in the upper parts of channel-fill sequences, 4- Normally graded muddy sandstone to mudstone Distinctive, matrix-rich medium to thick-bedded, fine to coarse-grained non-amalgamated sandstones, they are extremely mud-rich, and the upper parts of the beds sometime display a distinctive facies with small mud-flakes and contorted lamination. It has been suggested to form by the reconcentration of the tails of mud-rich sand-bearing turbidity currents, 5- Slumps, slides and debris flows intervals of differing dip are separated by discrete (slide) surfaces between which the dip is more or less uniform , and Thin beds dominantly thin-bedded facies that grade into one another.
Some of the common stages can be recognized in the channel evolution. Initially broad, relatively straight submarine valleys were cut through a process of slumping and submarine erosion most probably related to major sea level lowstands. The valleys were then completely filled before subsequent phases of reincision, which may be related to further lowstands. The reincised channels are generally more sinuous than the initial valley cuts and are characterized by a succession of nested thalweg channels. The cycles of erosion and the varying styles of deposition during the different stages of channel development can be considered in terms of slope equilibrium related to flow density, flow thickness, and the grain size of material in suspension.
Well logging: Explain how the program (TeckLog) worked, explain available data for this study, explain equation that are generally used to measure properties petrophysical and explain equation that we used in the current study. Was the work of some examples of some wells in the study area, such as raw data and corrected, the methods used to calculate the volume of the shale and the methods used to calculate the porosity, as well as to determine the water saturation and hydrocarbon saturation and explain method in which calculating the volume of the shale.
Reservoir Evaluation: A comprehensive formation evaluation was carried out for the Late Pliocene Simian Channel, section encountered in the seven selected wells inthe study area. Reservoir evaluation, that represents the main task in the present work, is conducted to evaluate the petrophysical parameters needed for formation evaluation. It includes, the determination of the volume of shale, porosities (total, secondary and effective), lithologic composition (shale and sand) and fluid saturation (water and, oil, gas,) for the studied members using the TechLog for the quantitative estimations of the subsurface sequence. The output results are presented, zone-wise, in two vertical crossplots, of the same depth scale, for each well. The first crossplot illustrates the corrected log data and the second one is a litho-saturation crossplot. Determine the contact between gas zone and water zone (GWC) can be easily recognized from the relation between the neutron, density and the response of resistivty logs in each well.Moreover, a number of Neutron-Density crossplots, Neutron-Sonic crossplots, and M-N crossplots relationships have been constructed to help identification type of the lithology, the value of the porosity and in addition to the gas and clay effect, Results of well log analysis were used in the evaluation of hydrocarbon potential in the study area.
from log analysis and interpretation Simian Cahnnel can be divided into two main unit, a thick unit of sandstone ranges between (78ft to 115ft thickness) and a small unit in the base of the channel (10ft to 25 ft thickness) mainly silty and shaly staff, the sand stone unit in varing in thickness relative to the core of the channel hence the wells in close to core of the channel has more sandstone thickness than the wells far from the channel core.
The petrophysical parameters computation and results of the reservoir rocks are represented by a number of isoparametric maps, which include: volume of shale, total porosity, effective porosity, water saturation, hydrocarbon saturation, reservoir and net pay thicknesses. These maps had been interpreted as a follows:
a) The volume of shale rangange in values from minimum value of (15 %) in Simian Di well to maximum value of (38 %) in Simian 2 well. Generally the shale content distribution decreases in the core of the channel and increase toward the levee of the channel.
b) The porosities analyses Shows variation in porosity values from minimum value (30 %) at Simian 1 well to maximum value (35 %) at Simian 2 well, shows an increase in the total porosity from levee of the channel to the core of the channel along the axis of the channel. While the highest valve of total porosity is concentrated aonge the axis of the channel. While the effective Porosity Distribution Map of the Simian channel shows minimum value of (11 %) in Simian 3 well and maximum value of (18 %) in Simian Dn well, generally the effective porosity is increasing from edge of the channel toward core of the channel along the channel axis of the channel
c) The water saturations show minimum value of (36 %) in Simian Dm well to maximum value of (64 %) in Simian-2 well. Generally the water saturation distribution increases from core of the channel toward the edge of the channel
along the channel core. While the hydrocarbon saturation shows traditionally a reverse pattern to that of the water saturation. It varies between 36 % and 64%.
The Hydrocarbon Potentialities of the study area can be discussed by integrating the lithological, petrophysical, fluid Parameters and hydrocarbon generation factors affecting on the investigated area which are achieved from the comprehensive analyses processes. Consequently, maps are constructed for the studied channel. These maps are based on pay zone thickness, hydrocarbon saturation, some reservoir petrophysical parameters such as effective porosity and volume of shale. These maps are helpful for the future developing of the study area and a guide for the future appraisal and Delelpment plan.
The Hydrocarbon Potential map of the simian channel reveals that the core of the channel is the optimize sites for development and production fron the channel where the levee part of the channel is promising sites for future development where it has high potential for gas bearing in the thin bedding part which is thick and wide and has good hydrocarbon saturation and good porosity specially the gas has high mobility which gives good apportunity for recovery.
Recommendations
- In this kind of reservoir which is characterized by high present of shale in all inervals including a thich sand intervals also has not compacted and soft sediments SP, and Sonic log is not recommended in formation evaluation hence no clear deflection between sand and shale so need to foucus more in the other tool in evaluation.
- In sand shale reservoir the volume of the shale is impoetant factor and has direct impact on the formation evaluation so new logging tichnology like Magnetic Resonance help to determine the shale content and amount of irreducabel water as well.