An oil well located offshore Southeast Asia, was completed with a dual string and after 20 years of production the drawdown decreased significantly even with gas lift mandrels located in the long string, 480m (1575ft.) above the lowest producing zone. A deep gas lift (DGL) system was installed based on field data that indicated the production could be improved by increasing the drawdown to optimize the gas lift performance. One of the main limitations was the depth of the production packer for the gas injection production. The deep gas lift system was selected as it enables the gas injection point to be moved deeper into the well, which in turn results in the ability to create a greater drawdown. The lowermost gas lift mandrel was straddled with two packers and a crossflow assembly that provided dual flow paths in a single system as well as suspending 350m (1148ft.) of 1.5in coiled tubing (CT) that acted as the injection string to a predetermined depth. The operation was the first of its kind in which the DGL system was conveyed with a CT Catenary system on board a dynamically positioned vessel (DP2); this enabled flexibility in deployment of the long bottomhole assemblies in small offshore platforms without the presence of a crane. For this operation, modifications were required in the original CT equipment to maintain well integrity, providing double barriers at every step of the installation. The DGL system was successfully and safely installed in a live well in 3 days. After its installation, the production rate increased tremendously. Similar operations will benefit from understanding the rationale in the selection of the solution, the details of the installation with the CT catenary system, the barrier systems put in place during the open-hole installation, the depth correlation methods and the lessons learned.

H E oceanographer appreciates the free drifting buoy. If drogued at depth and of T small wind resistance, it gives him useful information on the ocean currents at that depth. The meteorologist is not so keen. He would like the buoy to stay in one spot, namely that where there is a paucity of other information. However, while it is technically possible to moor buoys in very deep water, the costs and difficulties attendant on deployment and maintenance of such a system are enormous and a cheaper alternative would be invaluable. One such alternative is the quasi-stationary buoy. The concept is not a new one; Schlieben (1969) described an instrument platform, known as SKAMP (Fig. l), which was self locating within a fraction of a mile. The position of the buoy was detected by using the United States Navy satellite navigation system and the platform derived its propulsion from a rather complex skeined aerofoil sail system. Control of sail and rudder was handled by a small computer. Schlieben's early work clearly demonstated the potential of the self navigating buoy. He foresaw that buoys of this type could be programmed to sail to their required position, remain on station for a predetermined time and then return to a collecting area for servicing.

The Ufuq field, operated by Petroleum Development Oman (PDO), is located in Oman in close proximity to the Lekhwair field, the discovery well being drilled in early 2006. An appraisal well was subsequently drilled with the objective of further evaluating the discovery and delineating its' extent so that early commercial development decisions could be made. This second well was drilled with an extended horizontal section which identified a second zone of reservoir quality rock above the main zone of interest. As a consequence a second horizontal section was drilled to optimize the intersection of the two reservoir units and plans were made for evaluation testing. The first part of the test was planned to evaluate commingled flow while the second was to plug off the additional zone and flow test the main zone. To achieve these objectives, a unique combination of a 92º well inclination and an open hole scab liner were used with the scab liner providing a seat for an inflatable bridge plug to be set to isolate the upper zone once commingled testing was complete. Following testing of the main or lower zone the plug was retrieved thru-tubing and the well returned to commingled flow. In this paper the authors will review in detail the planning and execution of this procedure which avoided a workover, thereby saving 7 days of rig time, and was a "first" for both Operator and supplier. Introduction The Ufuq field is located close to the existing Lekhwair field and (See Fig. 1). Following the drilling of the discovery well in early 2006 a second well was drilled commencing in June 2006. The primary objective of the Ufuq-2 appraisal well was to provide the data needed to enable early decisions to be made as to the commercial viability of the discovery. Two vertical pilot holes were drilled which confirmed the presence of hydrocarbon bearing reservoir quality rock and established the presence of an Oil/Water contact (OWC).