Early water production and bypassed oil in edge water drive reservoirs
Document Type
Conference Proceeding
Publication Date
1-1-2004
Abstract
Conventionally, water coning is considered as a cause of early water production in bottom water drive reservoirs. However, in edge-water drive systems with unfavorable mobility ratios, water tongues may underrun oil and provide the conditions for water coning to partially completed wells. During initial production a water tongue commonly conforms to strike far from the well, and then forms a peak (or areal tongue), as it gets closer; finally, a water cone may form atop the tongue when it reaches the well. Water coning, tonguing, and their simultaneous interaction primarily affect the water breakthrough time, the post-breakthrough production, and therefore ultimate recovery. To date, the effects of water coning and tonguing on well production have been addressed separately. This study considers the two mechanisms as a chain of causality leading to excessive water problem and early termination of well’s life. The study demonstrates that the two combined effects may cause early water breakthrough (tonguing) and a very slow, ineffective oil recovery due to water coning. In this study, analytical expressions for diffuse and segregated flow conditions have been used to assess tonguing and coning severity while numerical reservoir simulation identified dominant reservoir conditions for water tonguing (early water production) and separately, the conditions for water coning and bypassed oil. Dimensionless scaling groups are used in a sensitivity analysis of a factorial design. Important engineering factors including well location, mobility ratio, gravity numbers, well penetration ratios, well spacing, and vertical permeability are analyzed. An example demonstrates how knowledge of factor influences can be used to select well location and completion length.
Publication Source (Journal or Book title)
Canadian International Petroleum Conference 2004, CIPC 2004
Recommended Citation
Arslan, O., Wojtanowicz, A., Kumar, A., & White, C. (2004). Early water production and bypassed oil in edge water drive reservoirs. Canadian International Petroleum Conference 2004, CIPC 2004 https://doi.org/10.2118/2004-269
