Reservoir-Surveillance Data Creates Value in Fractured-Carbonate Applications

Abstract

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 188192, “The Value of Reservoir Surveillance—Applications to Fractured Carbonates Under Waterflooding,” by Alaa F. Shbair, Hamdan Al Hammadi, John Ortiz, and Olanike Adeoye, SPE, ADCO; Medhat Abdou, ADNOC; and Luigi Saputelli, SPE, and Fahmi Bahrini, SPE, Frontender, prepared for the 2017 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 13–16 November. The paper has not been peer reviewed. Determination of the value of information (VOI) is a well-known process for justifying data acquisition, but engineers struggle to extract relevant information from historical data to apply a Bayesian approach. The objective of this paper is to illustrate a methodology for identifying the VOI in reservoir management—in particular, for deriving the conditional probabilities of success when new and imperfect data are acquired. Introduction Managers tend to avoid costs and production losses related to data acquisition. Pressure and rate transient analyses (PTA and RTA) along extended production time allow reservoir characterization and understanding of near-wellbore characteristics; however, PTA and RTA alone do not provide pressure- and fluid-distribution prediction beyond the wellbore. Such a task requires integration with reservoir simulation. The Role of Surveillance in Integrated Reservoir Management (IRM) IRM defines the supervision of activities designed to manage subsurface hydrocarbon reservoirs. IRM frameworks have been deployed across assets around the world to ensure that reservoir-management goals are achieved or exceeded. IRM has been proved to help (a) shorten learning curves, hence reducing total cycle time, resulting in increased productivity for an asset; (b) measure key performance indicators that allow integration of the correct multidisciplinary efforts in delivering consistent results; and (c) foster a culture that challenges the status quo continually. The role of surveillance in IRM is to improve the success and quality of reservoir-related activities (e.g., well work, rate control, and sustainable operations) continually while managing well integrity and concerns related to health, safety, and the environment (HSE) (e.g., manage the well-operating envelope and minimize HSE risk issues). To achieve consistent success, understanding reservoir performance and maintaining quality predictive models are paramount. These models are used to optimize well and reservoir performance continually (Fig. 1). Reservoir Surveillance Guidelines (RSGs). The RSGs are corporate surveillance guidelines that set long-term business drivers and expectations for best practices; they establish the minimum requirements for surveillance per technology maturity and readiness. RSGs are delivered through a system that provides minimum requirements for consistent well-surveillance activities, enabled by VOI methodology, remote monitoring, and data-driven models. Among the goals of the RSGs are the following: Maintain reservoir performance and well behavior within the optimal operating envelope Avoid unnecessary trips to the wellsite Recognize and warn personnel of unsafe operations Determine and alert personnel of abnormal well-integrity conditions