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Abstract This paper shows the results of a Pulse Test conducted in Egypt's Badri Field. The test was conducted to understand the degree of hydraulic communication within the reservoir and to check a suspected fluid migration towards the nearby El-Morgan Field. The test involved 6 wells, including the active well. The pulses were created by an alternate sequence of injection and shut-in periods of 36 hours each. The resulting pressure pulses were monitored in the observation wells for 12 days.
The observed pressure responses were analyzed by history matching techniques. The analytical solution of the diffusivity equation for a homogeneous rectangular reservoir with mixed boundary conditions yielded an excellent correspondence between measured and simulated pressure responses.
The test indicated good hydraulic communication within the investigated area. It also showed that there was no leak towards the neighboring El-Morgan Field as it was previously anticipated. In addition, it was possible to determine the interwell reservoir properties and the geometry of the area investigated during the test.
The test also suggested the presence of free gas in the upper part of the structure. This was confirmed by other sources of information.
Introduction Pulse-Testing is a special form of multiple-well testing. The technique uses a series of short-rate perturbations at the active wells. Pulses generally are alternating periods of production or injection and shut-in. The pressure response to the pulses is measured at the observation well(s). Since the pulses are of short duration, the pressure responses are small. Therefore special equipment is usually required to measure the small pressure variations. The advantages of the pulse testing compared with interference tests result from the relatively short pulse length and by the fact that the reservoir pressure trends and noise are automatically removed by using the appropriate analysis techniques. A pulse test may last from a few hours to a few days.
After the introduction of this method in 1966, interpretation procedures were further outlined by Culham, Startzman and Kamal and Brigham. The effects of wellbore storage and damage on multiple well testing techniques were studied by Prats and Scott and Jargon. Ogbe and Brigham outlined the effects of wellbore storage and skin at the active or observation well on the Pulse test response. It has been found that wellbore storage attenuates the response amplitude and increases the time lag of the pulse response. This effect is more pronounced when wellbore storage effects exist in both wells rather than one well.
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