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In the current high oil / low gas price North American environment, and considering the new options available for well completions technology in unconventional reservoirs, recent industry activities have turned their focus to the areas of Liquid Rich Shales (LRS) and Light Tight Oil (LTO) along with unconventional tight and shale gas (UG). Integrated workflows are important to the successful execution of this portfolio, i.e. systematic methodologies to screen and appraise opportunities, and cutting edge integrated technologies must be viewed as key enablers. It is also important to maintain a life-cycle mindset and leverage economies of scale to execute projects faster and more efficiently. This paper will discuss some of the advances and best practices that Shell has in each of the following disciplines, the value of R&D and applied technologies as well as integrated workflows used for exploration, appraisal and development of UG, LRS, and LTO plays: • Geological screening and sweet-spotting • Geomechanics evaluation and modeling • Reservoir engineering, including PVT sampling and characterization • Completions, stimulations and diagnostics • Artificial lift and operational considerations

Exploitation of unconventional resources is evolving rapidly. Case in point: liquid-rich shale (LRS) plays, once impermeable source rock, are now a prime target for unconventional exploration and development, with economic plays, such as the Eagle Ford, proving the potential. However, given complex and expensive completion, drilling and production operations combined with relatively low production rates and commodity prices, slim economic margins will likely prevail for the foreseeable future. Hence, the difference between economic success and failure could be the pace at which an economically robust development plan can be conceived, tested and implemented. With this in mind, entry into new plays must rapidly and intelligently build on all unconventional best practices to-date – of which there is no shortage. Unfortunately, most are presented as rules-of-thumb, intuitive-but-unquantifiable or come with a long caveat list. Thus, the authors of this paper chose to quantify the credible ranges of several selected best practices based on the belief that there are only a handful of key engineering and geological levers that have step-change influence on production and cost (as opposed to optimizations). We have built an unconventional development workflow that identifies them, quantifies them, risks them and constructs full field development scenarios, which are economically evaluated and ranked, using only initial exploration data. Thus, even early appraisal wells can be planned to mitigate development risks and ensure the highest value geological and engineering data is collected early and used to steer timely development decisions. The workflow is not novel, but at its core it accepts the inherent uncertainty of unconventional reservoirs and seeks to test end-member cases to drive decision making. This workflow was applied by Shell while planning the development of the Duvernay LRS play in Canada and will be described in that context. It consists of: Identifying the key, play specific development leversGathering and analyzing analogue play data on these leversConstructing individual well production profiles and economicsBuilding field development "end game" scenariosEvaluating full development economics to understand total project value and robustness

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To maximize the development value of the emerging Canadian Duvernay liquid rich shale (LRS) play quality risk-based decisions need to be made. These decisions must consider a number of complex variables that can all have a high impact on both short and long term economic viability. Credible ranges for variables such as well construction costs, production decline rates, infrastructure configurations, and commodity prices (e.g. oil price volatility witnessed in 2014) must be built. Quality decisions can then be made by leveraging a detailed understanding of the variables’ interdependencies and quantified economic impacts. This paper describes the construction and analysis of a suite of Duvernay scenarios developed by Shell Canada using sophisticated hydrocarbon planning software. They were built using a strategy table approach and focused on options for gas processing facilities. The impacts of drilling ramp-up timing, shallow cut versus deep cut configurations, and operator versus midstream build-own-and-operate (BO&O) were examined. For example, several midstreamers exist in the Duvernay play area with significant, non-optimal (sour and shallow cut) processing capacity. These facilities can be used today to capture initial value but require expansion in the future; therefore, an evaluation of all credible new build options is required to understand how best to develop the play. A suite of key comparative economic metrics, including net present value (NPV), profit to investment ratio (PIR), and payout period (POP), was generated. Expected monetary values (EMV) for each scenario were calculated and used to identify the optimal, risk-based approach. Additional insights were derived by comparing the scenarios, these insights included: the value of information associated with a longer appraisal period, the value of infrastructure flexibility, and the NGL recovery and product price thresholds required to justify deep cut construction.