TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractDevelopment and exploitation of oil and gas resources in increasingly difficult operating environments such as deepwater raise many technical challenges. Among these is the ability to provide assurance on the completions and production from high-cost and complex wells. Real-time, permanent wellbore and reservoir monitoring is a critical technology for providing assurance and maximizing profitability of these fields.Recent developments in fiber optic sensing technology have resulted in reliable alternatives to conventional electronic systems for permanent, downhole production and reservoir monitoring. In-well fiber optic sensors are now being developed and deployed in the field f or measuring temperature, pressure, flow rate, fluid phase fraction, and seismic response. Bragg grating-based fiber optic systems combine a high level of reliability, accuracy, resolution and stability with the ability to multiplex sensors on a single fiber, enabling complex and multilateral wells to be fully instrumented with a single wellhead penetration. These systems are being installed worldwide in a variety of operating environments for a variety of applications.This paper presents several recent deployments of in-well fiber optic monitoring systems, including descriptions of the downhole sensor assemblies, installations, and measured data. Installations of fiber optic pressure and temperature systems in a land well and in the Gulf of Mexico and an all-fiber flow and liquid fraction system in deepwater Gulf of Mexico are discussed. A general description of fiber optic sensing and Bragg grating-based sensing systems is also presented.

Offshore developments in deepwater are very high cost ventures in complexreservoir environments. Seismic imaging challenges induce significantuncertainty in reservoir descriptions. Reservoir surveillance, especiallyinflow distribution across the reservoir interval, is a valuable contributor tounderstanding reservoir performance however acquiring this information usingconventional technology, such as production logging tools, is very problematicin the deepwater environment where wireline intervention into live wells is amajor risk and cost. Intelligent chemical tracers are a new technology that provides insight intothe inflow distribution without intervention operations or major alterations tothe completion design. The tracers consist of smart plastic and unique chemicalcompounds that are combined into a matrix that resembles strips of plastic. Thematrix is designed to be sensitive to either oil or water. For example, whenwater sensitive matrix is contacted by water, the matrix releases its uniquechemical fingerprint (tracer) at a prescribed rate. The water sensitive matrixis dormant when contacted by oil, gas or air. Oil sensitive matrix behavesexactly the same way but with oil being the target fluid. Unique chemical tracers are deployed at strategic locations in the completionso that fluids entering the completion contact the tracers. At the surface, samples are taken and analyzed for the presence and concentration of eachunique tracer that has been deployed in the completion. The concentration datais plotted vs time and produced fluid. Analysis of these plots can yieldanswers to very valuable reservoir management questions like:Are all the intervals producing?What is the relative contribution of each interval?Where is water break-thru occurring? This paper reviews:How the technology works.Interpretation techniques.Case histories of intelligent tracer responses.The value this knowledge can bring to deepwater reservoir management.

DownHole Flow Control (DHFC) is a technology that was originally developed to remotely control the production from multiple reservoirs in the same well. BP recognized the value of using this capability in injection wells to manage the injection of water into separate reservoirs. BP's Field of the Future program worked with service providers to develop the capability of "choking downhole flow-control for water injectors" that allows one well to serve the role of two injection wells thereby reducing the number of injection wells required for field development. At Intelligent Energy 2008, BP reported on development and qualification of DHFC technology for high rate water injection (SPE Paper No. 112143). Since then, BP has implemented the newly developed DHFC technology in two fields with over a dozen installations. BP has achieved its goals in one field and not achieved its goals in another field. This paper reviews the key learnings associated with both the successes and the failures. A summary of key learnings: The DHFC technology is very reliable, although difficulties have been experienced with some of the associated multizone completion technologies.Remotely operating the valves to vary the injection rate has proven to be a straightforward operation.Higher than expected injection pressure in excess of the maximum differential pressure rating of the open hole isolation packer in one field is preventing the DHFC system from achieving its objective. In summary, DHFC application for high rate water injectors is considered a success. Development engineering continues on open hole isolation packers to allow deployment of DHFC in fields with high injection pressure requirements.

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