Development of Unconventional Resources in North Africa: Evaluation Approach

Abstract

The "Shale Gas Revolution" in North America has created both an opportunity and a challenge for the North Africa region for finding such unconventional resources. Approaches to finding them must be based on technology and planning to avoid unwanted expenses and error. Unconventional resources, for the purpose of this paper, are defined as tight and/or shale gas resources, although in North Africa, many of the challenges and potential solutions are equally applicable to oil rich resources. Key challenges specific to the North Africa region include the following: The availability of gas in North America has shifted LNG shipments to Europe (which is North Africa's biggest export market). The potential spread of this "revolution" to Europe could further erode the region's market share. The region faces a lack of infrastructure and a higher cost base for developing unconventional resources. As a result, little margin for error exists, nor can you afford to "learn by the drill bit." Therefore, you need to apply technology to reduce costs and increase well productivity and you need to develop a methodology that ensures minimal iterations. The latter requires a fully integrated approach to project evaluation, planning, and execution. As the highest portion of costs associated with developing shale/tight gas resources is for hydraulic stimulation (fracturing), this paper will focus on the best way to integrate: Reservoir characteristics (rock and fluid properties) Geomechanics Fracturing techniques A synergy of reservoir consultancy and pumping services has developed a close rapport and integrated approach that could be used by resource holders. This methodology can be modified to fit the requirements of NOCs or IOCs. This paper aims to highlight these and also offer a potential approach and methodology to evaluate these unconventional resources and secondly to apply technology to unlock their potential. Case studies will be used to demonstrate the pitfalls and challenges faced by projects in North America.

Fracturing Fluids and Their Application in the Republic of Croatia

“…The two main functions of a fracturing fluid during hydraulic fracturing are the transfer of energy from the frac pumps to the formation, creating the fracture and the transport and suspending the proppant. Since the goal of hydraulic fracturing is to increase the production of hydrocarbon, a fracturing fluid must be compatible with the formation minerals, minimize proppant pack and surrounding formation damage and be easily recovered after hydraulic fracturing [19].…”

“…Fracturing fluids are divided into seven categories: water-based fluids, oil-based fluids, acid-based fluids, alcohol-based fluids, energized fluids, foams, and emulsions [47]. The classification, type, composition, advantages, and disadvantages of fracturing fluids are presented in Tables 4-10 modified according to [7,19,21,48,49]…”

“…According to the base fluid, the following fracturing fluids are distinguished: waterbased fluids, fluids based on produced water, oil-based fluids, acid-based fluids, alcoholbased fluids, foam-based fluids, emulsion-based fluids and energized (cryogenic) fluids (CO 2 , N 2 , etc.) [2,6,7,[19][20][21]. Each of these fluids has its advantages and disadvantages and a specific area of application.…”

Feasibility analysis on coiled tubing jet fracturing with supercritical CO2

“…While production of the easy-to-recover oil and gas declines worldwide, unconventional oil and gas resources, including shale gas, coal bed methane (CBM), tight gas, heavy oil, have been recognized as important alternative energy sources [1,2]. Hydraulic fracturing technique plays an important role in the development of unconventional oil and gas reservoirs.…”

Quantitative evaluation of the diagenesis and porosity evolution of tight sandstone reservoirs: A case study of the Yanchang formation in the Southern Ordos basin, China

“…Unconventional oil plays with considerable resources are receiving increasing attention [1]- [5]. At the end of 2010, the total proven remaining oil reserves in the global conventional petroleum plays amounted to 1888×108t, accounting for 40% of the global oil and gas reserves [6].…”