As producing companies search for hydrocarbon resources, it has become necessary to pursue opportunities in frontier geologic horizons and geographic locations. As such, the severe environment in these wells requires special testing and completion equipment that can sustain the expected operating conditions.
In a gas condensate field in western Siberia a pilot project with 6 wells is planned to get the maximum reservoir, drilling and production information as a basis to optimize the full field development. The depth of the hydrocarbon bearing formation in the subject field is 3700 m, with a reservoir pressure and temperature of 610 bars and 110 deg C respectively. The wells will penetrate up to 500 m of permafrost, and two relatively low pressure zones before reaching the target. To achieve the objectives of the pilot phase and well testing operation, special testing processes have been designed to reduce the risks in achieving successful evaluations, and these wells can be successfully tested under both rig-supported and rigless operations.
The former tests were conducted with the rig and each zone was tested with an open annulus completion string. After each test the zone was plugged with cement.
The new challenges is to test each zone individually without rig on location and without damaging the zones after testing and at the same time improving the quality of the test data and improve the PVT sampling procedures by collecting a representative samples, which is questionable to date. This paper discusses the pilot wells objectives, application, and value of achieving the pilot wells objectives, also the challenges and unique aspects of the arctic environment the project has to deal with and present the process of reducing the well test and completion cost and achieving the full test objectives.
The prospect is located in the northern part of Western Siberian region, It is an under saturated gas condensate reservoir. The FFD (Full Field Development) of this prospect is a project, which last 40 years, consisting of an 88 well drilling program.