Effluent Water Disposal in Two Giant Oil Fields in Northern Kuwait
Peter F. Cameron1*, Ali N. Khan1, and Noel Lucas2
Two major carbonate reservoirs are being used for effluent water disposal in the Raudhatain and Sabiriyah oil fields in northern Kuwait. These are the Paleocene Radhuma and Maastrichian Tayarat formations. A detailed reservoir characterization study of these formations was initiated in 2006. The purpose of the study was to develop an understanding of the injectivity capabilities of the reservoirs and to determine the medium-term plan for water-injection capability over the period to 2010 to ensure zero surface disposal of water to evaporation pits. A 3-D model was built, which included the 39 major faults located in both fields. Seismic inversion was applied, and a petrophysical interpretation of the limited log data set was used to populate the property model. The model illustrated that the upper Radhuma layers have the best porosity and permeability, although to date the injectivity data suggested a lower Tayarat dolomite layer has the best capability for water disposal. Dynamic testing and history-matching of the model demonstrated that the crestal area of both fields will likely pressure-up in the near-term, especially in the immediate vicinity of the disposal wells, but the flanks of both fields will undergo relatively moderate pressure build-up over a four-year injectivity period. The dynamic modeling suggested that the flank and mid-flank areas of both fields, where porosity and permeability are present, may be the best areas to locate effluent water wells that will have good injectivity and moderate pressure gain over a sustained time period.
AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain