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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.

The shale gas revolution on North America has created an incentive for the rest of the world to chase this challenging hydrocarbon resource. Currently around 44% of the 20.6 tcf annual gas production in the US occurs from unconventional resources, with this forecast to rise to 65% by 2020. The pitfalls and challenges faced by North American development projects provide a wealth of experience, which can be used to understand how we can apply technology more effectively in Europe and North Africa. However, there are differences in both operating environments and gas markets between North America and Europe and North Africa, and we aim to highlight these differences as well as the similarities. Unconventional oil and gas projects in Europe and North Africa are currently at an early stage of their life cycle, exploration and appraisal. We identify the following key challenges for the European region: The potential spread of the North American unconventional gas revolution to Europe and North Africa could create competition and depress gas prices. Reduced gas prices and increased costs will considerably reduce the margin for error in exploring for unconventional gas. Therefore there is a need to apply technology effectively, to avoid having to learn "by the drill bit".A lack of infrastructure and specialised equipment, particularly in North Africa, leading to a higher cost base for developing the region’s unconventional resources.The regulatory environment in Europe is not presently conducive to development of shale gas resources together with the negative public perception of the environmental risk associated with shale gas development. Aside from these medium to long term challenges, Europe at present is facing a more critical short term challenge: the need to prove the concept by completing and producing the first economic shale gas wells. To overcome these challenges, operating and service companies need to apply technology effectively and efficiently at an early stage in shale resource development. This paper offers a potential approach and methodology first to evaluate unconventional resources, and secondly to apply technology to unlock their potential. An integrated oilfield service approach could make unconventional gas appraisal outside of North America economically feasible and sustainable. As in conventional reservoir developments, detailed reservoir description can be used to optimize reservoir penetrations and predict well performance. In the second part of this paper we discuss how a Shale Engineering workflow that will improve the effectiveness of interaction between operators and service companies, and enable commercial production of unconventional resources outside North America. Unconventional reservoirs are defined for the purposes of this paper as oil and gas reservoirs that exhibit low permeability such that hydrocarbons cannot be produced at economic rates without stimulation of the reservoir.

The industry is undergoing a transformational change, driven by increases in exploration and development costs in the last decade, combined with falling oil prices in recent months. As a result, there is an increased interest in squeezing more from mature assets. The general message is that a 1% increase in recovery factor could result in two additional years of global oil and gas supply; however, industry experts know how difficult it is to increase recovery from mature fields. This paper presents a novel screening method that enables a large number of scenarios to be considered and facilitates convergence on potential solutions. By 2018, 70% of global oil production (more than 80 million B/D) is projected to come from mature fields (Fig. 1). Some major exploration and production (E&P) operators already have more than 70% of their portfolios in production decline. This global trend, combined with the pressure to reduce the cost per BOE resulting from declining oil prices, has pushed E&P operators to place a renewed emphasis on mature fields. This paper presents an integrated approach to revitalizing mature fields and addresses this new reality by focusing on three key areas: immediate impact solutions, reservoir optimization, and new pay. The first step in this process is a screening and ranking method for mature field revitalization choices, which enables feasible options to be identified at an early stage, thus avoiding wasted time and money pursuing unfeasible and/or uneconomic options. A common challenge for the operators of mature assets is filtering the vast array of issues and potential solutions. This unique screening method leverages a global reservoir analog screening database combined with technical and economic modeling techniques to help ensure that the optimum revitalization strategy for the reservoir is achieved. In many cases, the proposed solutions may be technically interesting, but very expensive or operationally not feasible. This paper explains how the proposed revitalization plans must be combined with a fully integrated end-to-end solution, from planning, design, and simulation to field implementation. Case studies are shared to demonstrate how this integrated approach, linking concept to implementation, can avoid expensive iterations and help to enable mature field production uplift.

As engineers and scientists, we are very familiar with analysing technical risks, developing mitigation plans and implementing the plans that are safe and technically feasible. At the same time, dealing with subsurface projects has made us adept at analysing and understanding technical uncertainties. Furthermore, because of the large investments involved in upstream projects we are regularly exposed to commercial issues. However, the optimum situation is when the technical and commercial risks and uncertainties are evaluated in an integrated fashion.