الفهرس 
SCOPE AND AIM OF STUDY
REGIONAL GEOLOGICAL SETTINGOnly 14 pages are availabe for public view
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Abstract
The present study deals with evaluation of the Surface and Subsurface structural
framework and reservoir characteristics. This is to evaluate the hydrocarbon potentialities of
the study area Qasr oil Field (Shushan basin) which is located at the north Western Desert of
Egypt, about 7.5 Km south of the Mediterranean coast.
The data include 2D and 3D seismic data, composite logs, electrical logs, cores and
plugs results from the available exploration wells were utilized in this study. The AEB-3D
rock unit is a part of the Lower Cretaceous Alam El Bueib Formation, and is considered as
the main oil producing reservoir in the study area. The Lower Cretaceous Alam El Bueib
sand (AEB) was interpreted, as stacked channel and point bar fluvio-deltaic sands, with
interbedded shales and some limestones or dolomites. The oil is trapped in stratigraphic or
structural three-way dip closures or a combination of both.
This work aims to find new drilling sites for further field development in the future,
where the reservoir compartmentalization model can be updated, based on the data available
from new wells. Furthermore, the analysis of electric well logs, reservoir pressure
measurements and sedimentological core descriptions can help in the detection of sand
channels and to predict their directions. Lithological interpretation showed two sand zones,
with average thickness of 30-50 ft. in most wells. They are separated by inter-zones layers
of about 10-50 ft. (distance). The interpretation of well logs, coupled with the core
descriptions, showed that, Alam El Bueib-3D rock unit is subdivided laterally into two sand
channels. Both are deposited in a high energy tidal environment. Well correlations, mapping
and analysis of the pressure measurements showed that, the directions of these channels are
most probably northeast to southwest. In addition, the effect of stratigraphy and structures
led to a number of reservoir compartments with varying pressure values, either vertically or
horizontally.
Picking and interpretation of the ten horizons from Lower Safa to Dabaa Formation
which done by tying seismic data (time) with well data (depth). Seismic profiles illustrated
the Surface and subsurface structural framework of the Lower Safa and Alam El Buieb
reservoirs. It can be demonstrated that 3D structural modeling described the structural compartments of the study area by displaying cross sections along any direction and through
any well location of the model’s data base. This can be used to propose locations for future
exploration wells in the area.
Structurally, Qasr oil field is represented by horsts and grabens. Large
accumulations of hydrocarbons have been trapped along the NE-SW elongated, narrow and
asymmetrical tilted fault blocks.
The reservoir Petrophysics characteristics of the present study deals with the
determination of the reservoir properties by using different log responses imply good
reservoir quality. Petrophysical properties of Lower Safa and Alam El Buieb reservoirs are
represented in the form of isoparametric maps which include shale volume (Vsh), gross
sand, total porosity, effective porosity, water saturation (Sw), net pay, net/gross thickness,
hydrocarbon saturation (Sh), residual hydrocarbon saturation (Shr) and movable
hydrocarbon saturation (Shm) to show their horizontal distributions of the Lower Safa
reservoir. The well log analysis of the Lower Safa and Alam El Buieb reservoirs using
different types of the cross-plots such as density neutron that shows the Lower Safa
reservoir is mainly sandstones with some calcareous cement. According to the pressure
analysis, the hydrocarbon type of Lower Safa reservoir in Qasr oil Field field is mainly
light hydrocarbon.
The source and reservoir rocks are all sandstones, while the seal rocks are the
local intra-formational shales. The oil in sandstones is of 22-35 API. Porosity, permeability
and water saturation ranges of the reservoir pay zones are 15-30%, 100-300 md and 20-
50%, respectively
Data integration of all input data with each other by the Petrel TM ,
Schlumberger’s software. The results of this study showed improve in the reservoir
characterization of the Lower Safa and Alam El Buieb Formations, help to identify potential
hydrocarbons present and hence will aid increasing the cumulative reserves in the
concerning area. The integrated data has been used to support the exploration and
development in the future field planning.