Water Based Mud In Oil & Gas Wells
The mud system used most frequently throughout the industry is the water-based system. Water is the continuous phase, but it may contain oil (i.e., emulsion muds) (check also: Oil Based Mud) or air (i.e., aerated mud) as the discontinuous phase. The oil must remain as segregated droplets and not combine in a distinct phase termed "discontinuous" (Fig. 1).

Fig.1:
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