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Water which is produced from the water reservoir and hence not adding to sweeping the hydrocarbons sweep.
It is a opposite to Good Water which is produced from the same reservoir as hydrocarbons and hence helping to sweep hydrocarbons.
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Fig. 1.1. Perforated reservoir A2 producing bad water as this water is not coming along with hydrocarbons. Compare with good water production in A1from A1, where water is coming along with hydrocarbons. | Fig. 1.2. Perforated Non-perforated reservoir A2 producing bad water as this water is not coming along with hydrocarbons. Compare with good water production in A1 which is linked to A2 through behind-casing channel. |
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