Unconventional Reservoir Development in Egypt's Western Desert: Lessons Learned From the First Appraisal Wells
- Mohamed Salah (Shell, Cairo) | Mazher Ibrahim (Apache, Houston)
- Document ID
- Unconventional Resources Technology Conference
- SPE/AAPG/SEG Unconventional Resources Technology Conference, 23-25 July, Houston, Texas, USA
- Publication Date
- Document Type
- Conference Paper
- 2018. Unconventional Resources Technology Conference
- 5 in the last 30 days
- 108 since 2007
- Show more detail
|SPE Member Price:||USD 9.50|
|SPE Non-Member Price:||USD 28.00|
Most of the Egypt's Western Desert plays are characterized as tight reservoirs. In early development stages, only the high permeability layers called “conventional reservoirs” were produced. The unconventional, challenging layers were not considered economical because of the high stimulation costs. As the high-permeability layers became more mature and showed a sharp decline in production, the tight layers/zones were targeted by operators to unlock the enormous amount of hydrocarbons and to achieve the economical production targets from these marginal fields. The government has launched a number of studies to evaluate, explore, and appraise several prospects of unconventional reservoirs. Gas shales were characterized within the Khatatba source rock in the Shoushan basin and a tight carbonate reservoir was observed in the Abu Gharadig basin. A total of six vertical and two horizontal exploratory wells were drilled and completed via multistage hydraulic fracturing in the appraisal stage of the program for collecting the required data. The pilot data were used to evaluate the reservoir quality, to demonstrate the availability of reserves, to identify the optimal technology for maximizing productivity, and to set foundations for the future development of these plays.
This paper presents the previous results of field trials and shares some lessons related to the recent appraising and development activities of unconventional plays in Egypt. The properties of these unconventional resources have been reviewed to unlock their potential. In addition, the best strategies of field development were highlighted to capitalize the promising potential from these reservoirs through an advanced workflow. This study sheds light on the recent unconventional gas appraisal and development activities. The results indicate that Egypt holds substantial resources of unconventional gas that can play a key role in positively changing the country's production.
Developing unconventional resources and unlocking the enormous amounts of hydrocarbons are gaining more interest. Achieving economical production targets is of key importance, particularly because of the increase in Egypt's domestic demand for energy and production's annual decline from the more mature, high permeability layers. Also, the enormous success in North America's production brought unconventional resources to the forefront of discussion on the future of energy. Five vertical and two horizontal exploratory wells have been drilled and completed via multistage hydraulic fracturing in the Apollonia tight carbonate. Another vertical exploratory well has been drilled and completed in the Middle Jurassic Khatatba source rock with one-stage hydraulic fracturing. Then the well has been flowed back. The goal of this appraisal program was to collect the required data and to set the foundation for the future development of these plays. Laboratory core testing was conducted to understand the complex mineralogy, reservoir characterization, and variable rock fabric. Geological and geochemical studies were conducted to identify the lithostratigraphic section of the Khatatba source rock and to measure the total organic content (TOC), the Rock Eval pyrolosis, and the thermal maturity of hydrocarbon and gas content. Geomechanical rock properties, derived from the advanced petrophysical analysis of newly acquired high-definition triple combo, full-wave sonic logs and core samples testing, were used to determine the rock elastic properties (the Young's modulus and the Poisson's ratio), brittleness and fracturability, and the natural fractures existence (Salah et al., 2016a). Understanding of all of these characteristics helped in reducing uncertainty during hydraulic fracturing operations. Moreover, a stimulation model, which integrated petrophysical and geomechanical data, was built. This paper reviews the findings of the recent activities within unconventional plays in Egypt and summarizes the formation properties, reservoir characteristics, and the flow back analysis of these wells. The lessons learned can form a basis for the subsequent development of various unconventional plays in Egypt.
|File Size||3 MB||Number of Pages||18|