A New Method for the Detection of Wellbore Phase Redistribution Effects During Pressure Transient Analysis

摘要

Pressure – Time data obtained during a pressure transient testinclude the effect of non-reservoir factors besides the reservoirresponse. Improper diagnosis to differentiate betweenreservoir and non-reservoir effects causes misinterpretation ofwell test data. Phase redistribution is one of the major nonreservoirfactors. Even the best available diagnostictechniques fail to detect the phase redistribution effects whenthey are not obvious from the analysis plots and the data donot match the pressure derivative type curves over thecomplete time range. One can only suspect the phaseredistribution in this case. Verification of anomalous effectdue to wellbore phase redistribution is required. In the field ofexploration geophysics, there have been established methodsfor the detection of anomalies in the gravity, magnetic orseismic data. In this paper new analysis techniques besidessome of the major techniques from exploration geophysics areapplied to transient well test data. And their relative success isdiscussed for the detection of wellbore phase redistributioneffects.