drilling mud

American  

noun

1. a water-based or oil-based suspension of clays pumped into an oil well during drilling in order to seal off porous rock layers, equalize the pressure, cool the bit, and flush out the cuttings.

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drilling mud British  

noun

1. a mixture of clays, water, and chemicals pumped down the drill string while an oil well is being drilled to lubricate the mechanism, carry away rock cuttings, and maintain pressure so that oil or gas does not escape

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Example Sentences

The Minnesota agency investigation found that Enbridge violated regulations when it discharged construction storm water into wetlands and inadvertently releasing drilling mud into surface water at 12 locations in June and August of 2021.

From Seattle Times • Oct. 17, 2022

Some 42,000 gallons of drilling mud spewed across the tundra, and several residents later complained of respiratory ailments.

From Washington Post • Mar. 10, 2022

Ten years ago: Engineers began pumping heavy drilling mud into the blown-out Gulf of Mexico oil well in an attempt to permanently plug the leak.

From Washington Times • Aug. 3, 2020

No one was injured, but residents and pedestrians captured video of oil, gas, drilling mud and other debris blasted into the sky.

From Los Angeles Times • Mar. 5, 2020

Soon after, at a community meeting, Friel Otten learned that, if drilling mud leaked into the aquifer, calcium levels in her tap water could spike.

From The New Yorker • Oct. 26, 2018