الفهرس 
Introduction and Geological SettingOnly 14 pages are availabe for public view
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Abstract
South Abu El Gharadig Field (SAG) which is located in WD-30 Development lease and Alam El Shawish East (AES-E) field which is located in AES-3&4 development leases, they are basically forming one extended field across the block boundaries of WD-30 development lease (owned by EGPC and Apache and operated by Khalda petroleum company) and AES-E3&4 development leases (owned by EGPC and Naftogaz and operated by Petrosennan petroleum company),respectively. The perimeter of the study field at about 11 Km north east AG Field is located which is the oldest oil and gas field in Western Desert.
The SAG/AES-E structure is producing from the horst block and the southwest down thrown side which is called AG-88, both compartments are extended across the leases boundary.
Structural mapping of the Cretaceous rocks using the converted 2D seismic lines to 3D seismic cube and by means of the interpreting 13 main horizons from the deepest mappable horizon (estimated Top Early Jurassic) to the shallowest horizon (Oligocene time, Top Dabaa) and creating isopach maps and 2D restoration showed the evolution of this part of AG basin by extension of NW-SE tectonic event that started in Early Jurassic time and it was responsible for creating the Mesozoic AG basin going through the extension rotation towards NE-SW trend in Early cretaceous time that continued during the deposition of Kharita Formation up to Khoman-B Member, then after the deposition of Santonian Khoman-B Member, the first pulse of the compression tectonics had started, that affected the north east African plate and appears in the northern Western Desert to north Sinai in the series of NE-SW folds and extended towards Levantine basin and it’s called “the Syrian Arc Folds”. These pulses continued to Early Tertiary and resulted in inverted the deep-seated rift faults and evolve the two-way-dip structure of SAG/AES-E Field.
The surgical mapping and mapping of the top and base of each reservoir interval using color inversion cube and the extracted attributes reveal the facies distribution across the area and show the entry points of the systems in the clastic reservoirs of ARC,E,G,UBAH and LBAH which are the main reservoir intervals in SAG/AES-E, and provide illustration about the confined paths of these system from the entry point from the southeast direction to the basin to the northwest direction where the fairways becomes unconfined and lobate or forms basin floor fan towards the rift basin to the North of the study area.
Well log evaluation of 8 wells and the analysis of conventional core of three wells in addition to one special core data provided the main properties such as porosity, volume of shale, net to gross, water saturation and permeability of (SAG/AES-E) reservoirs which are forming one extended field across the leases boundary, the SAG/AES-E extended structure is produced from the horst block and from the SW down thrown side. MDT pressure analysis provided a sight about the possibility of the communication of the reservoirs across the lease boundary and across the structure compartments and it concluded that the down thrown side of the structure are in pressure communication with the up-thrown side in Abu Roash- C, D, E members and top most part of ARG Member, then the SW en-echelon faults that bound the SW side of the structure become connected and provided sealing between the up thrown and down-thrown sides, but the MDT pressure were provided at the early stage of the field life, hence it shouldn’t be taken as the only source to prove communication of the extended reservoirs and the gauge pressures are needed to assure the reservoir communication and the geophysical study of field could also be the other source to describe the reservoirs and possibility to be extended and represent one extended field. The calculated pay parameters for all reservoirs ranges are (PHIT of 17 - 25 %), (N/G of 8 - 25 %) and (Sw of 10 - 30%).
The development of the extended fields is subjected to a legal act called Unitization process which allows the leases holders to develop the straddle reservoir as a unit and it’s a condition to start production from the extended fields as per the petroleum agreements. The original hydrocarbon pore volume (OHPV) is calculated for all reservoirs to assign the calculated volumetric to reservoir condition as it’s proved presence of the gas cap in the reservoirs and this may cause phase change during production across the field.
The total calculated OHPV in WD-30 is about 319.5 mmbbls and about 35.4 mmbbls in AES-E development leases and by considering the field as one unit and split the only extended reservoirs between the development leases proportionally with the percentile of the reservoirs extent in each lease, WD-30 development lease will hold 276.4 mmbbls while the AES-E will hold 35.4 mmbbls this represents tract participation of WD-30 88.5 % and the tract participation of AES-E lease is 11.5%.
This study could have been improved if the 3D seismic data is available to perform all the adjustment and noise filtration and seismic inversion and attributes on a real 3D cube and to avoid the data edge issues e.g. unclear attributes at this area. There is an overlap between the two surveys, that could have used to enhance the image by reprocessing the two surveys together, to get advantage of having multi-folding at this area.
The dynamic data e.g. gauge pressure and production performance are highly important, as a direct indicator of the communication of the compartments of the structure and the presence of stoppable e.g. faults or stratigraphic pinch cuts, which could compartmentalize the trap.
Compiling all the available Pressure Volume Temperature “PVT” analysis are highly needed to determine the gas and oil contacts, hence both OOIP and OGIP can be determined and dissect the different fluid reserves between the companies, as each fluid has changeable value with commodity price and the local market needs and different production share according to the petroleum agreements.
Finally, the saturation height function, could be a great contribution to determine the water saturation at the wells that have capillary pressure measurements, it also could have been used to calibrate the un-cored wells, to validate the assumed parameters that have been used in determining the water saturation by Archie equation.