Although the recent focus in the industry on maximum reservoir contact (MRC) and Advanced well completions has provided significant improvements in reservoir depletion it has caused some data gathering disruptions for companies operating these wells. In particular, the options to perform well logging are much reduced, and the costs of performing a production log are extremely high. This is related to both the costs of the more advanced horizontal well logging tools and the more expensive logging methods, such as coiled tubing and tracker systems, used for the conveyance of these tools into the wellbore. In an effort to acquire high quality downhole data in a timely manner in MRC wells, Saudi Aramco set about investigating the alternatives to traditional production logging methods. A technology gaining greater industry acceptance in recent years is permanently installed Distributed Temperature Sensing (DTS) and this became the focus of investigation. The limitations of conventional DTS technology was, however, soon realized; In particular the limited temperature resolution offered was not sufficient for evaluating high angle maximum reservoir contact intelligent wells. At the time of investigation a new generation of DTS technology became commercially available, providing a 10-fold improvement in measurement resolution. This allowed Saudi Aramco to proceed with field trials of the technology. This paper will present the requirements for advanced DTS technology to provide quality data sets for use in rate and density modeling in highly deviated MRC wells. In addition, the installation of the downhole hardware in an advanced well completion and the data from the field trials will be presented. Background Over the past six years, Saudi Aramco has pioneered the use of Smart and Intelligent well systems in its MRC wells to reduce development costs and prolong unwanted water production and control early gas breakthrough. Saudi Aramco's original maximum reservoir contract (MRC) wells included openhole laterals drilled from a 7" completion liner to provide the required contact/reservoir foot print to optimize rate and recovery 1. More recent designs have utilized smart well completion technology in the 7" cased mother-bore to control inflow from each lateral to extend well life and increase recovery (as seen in Figure 1). In the event of water/gas break through in any lateral, the downhole valves are remotely operated from the surface through hydraulic and instrument lines run outside the production tubing.

Intelligent and multi laterals wells are evolving as key completion technologies to enhance and maximize hydrocarbon recovery. A pre-requisite for the successful application of multi lateral and intelligent well systems is zonal isolation and compartmentalization of the reservoir. Current Techniques either involve the cementing of the mother-bore and/or the use of complex mechanical systems and packers to isolate individual zones. Both techniques increase the complexity of the operation and result in reduced ID from the additional casing string. In addition with intelligent well systems, a feed through system for the hydraulic, electrical or fiber optic cable must be used across the isolation device. This join or break represents another weak link or potential failure point in the system. An isolation device has been developed which uses a rubber elastomer bonded onto a base pipe. The rubber swells in hydrocarbon and provides an effective seal down hole between the base pipe and the openhole to maintain zonal isolation in even the most complex environments. Any number of packers can be made up in the completion string to provide the zonal isolation required and are run as an integral part of the completion string in a single trip. The swell packer offers many advantages over conventional techniques, besides it simplicity it is able to conform to irregular wellbores, the system can seal in open hole eliminating the need for a completion liner for zonal isolation. This saves rig time and money in the completions and allows for larger ICV's to be run. In addition, the use of a unique feed through system allows control lines and fiber optic cables to be run through the packer without a connection or splice at the packer. This paper will describe recent case histories and planned operations in Saudi Aramco where the swell packer has enabled intelligent completions, multi lateral, and reservoir compartmentalization for equalizer completions and simplified the process of cable feed through on intelligent completions. 1. Background Aramco has successfully utliized both horizontal and MRC wells (multi lateral with greater than 8km of reservoir contact) to enhance and maximize hydrocarbon recovery from its reservoirs. In recent years, the intergration of both intelligent and passive inflow control completion systems have further enhanced the value of MRC well by providing inflow control, better inflow profiles, and downhole monitoring capabilities. Saudi Aramco's first intelligent well completions were drilled as 7″ fullbore wells. A cemented 7″ liner was placed below the conventional 9–5/8″ casing provided the lateral isoallteion and a means to conventionally drill the TAML level two multi lateral wells. Standard 3–1/2″ ICV's and mechanical packers were used to provide the required intelligent well completion. (see figure 1.)

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