Chemistry and Chemical Disasters. (n.) Drilling Fluids. A very weak base, ZnO, which can be used as a sulfide scavenger in oil-base or synthetic-base muds. See: Garrett Gas Train, Hydrogen Sulfide, Oil-Base Mud, Scavenger, Sulfide, Synthetic-Base Mud, Zinc Basic Carbonate, Zinc Bromide, Zinc Carbonate, Zinc Chloride