An Application Of Engineering And Geological Technologies To Improve Production Performance In The Kareem Reservoir Of North El-Morgan Field
Authors: Hady Ismail A. , Rady M. , Woodward D.E. 
Published: December 2007

This paper summarizes the results of a recent comprehensive geological/engineering study to improve areal and vertical injection conformance and thus add new reserves in north El-Morgan field.

The geological complexity of the reservoir, lack of communication across faults and high stratification has led to trapped resources. This phenomena has also divided the reservoir into separate performance zones and areas. These problems are discussed in detail in this paper.

In general, a work plan was implemented to achieve maximum oil recovery by:further identification of fault trends,identifying unswept areas anddrilling and converting new wells.

As a results of this study 4 wells have been drilled as producers during 1995 resulting in an additional 7.5 MMBO reserves. The initial production rate of these wells was approximately 12,500 BOPD. In addition, one injector was drilled and two wells have been converted to injection to improve both vertical and areal sweep.

Post appraisal of new wells was performed. This analysis was helpful in explaining any significant differences between prognosis and actual results and was used to improve on future recommendations.

Introduction

An integrated geological and reservoir engineering study was conducted on the north El-Morgan Kareem reservoir. Re-interpretation of the structure was performed honoring the actual reservoir performance resulting in a new structure map satisfying both geological and engineering information. Mutual engineering and geological understanding plays a very important role in analyzing production problems and determining the proper remedial actions for improving reservoir performance. This paper will illustrate the data analysis and resulting actions taken to improve the performance of the reservoir. The waterflood in north El-Morgan has shown inefficient performance due to poor vertical and areal sweep efficiencies caused by the existence of a high permeability zone underlain by a lower permeability zone. Areal sweep is further degraded by the presence of faults which restrict fluid movement.

Geologic Setting

North El-Morgan field, located in the central part in the Gulf of Suez, is compose mainly of tilted fault blocks dipping to the west and south west. It is bounded from the east and north by the main clysmic fault and from the west by the oil water contact. The southern boundary is formed by the Belayim evaporites which were deposited unconformably over the eroded Kareem section separating the north and south El-Morgan fields. The Kareem section (Miocene) is the main producing zone in the field. It is divided geologically to 5 sub-zones according to the quality of the sandstone. These sub-zones are separated vertically by shale streaks which act as vertical barriers indicated from the pressure data. The main trend for the fault system in the field is due northwest-southeast, parallel to the main clysmic fault. These faults play a significant role in the movement of oil and water. Shale bodies, present in the Kareem, act as lateral seals for oil and water movement and consequently create areas with different pressure.

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