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

Meanwhile, opponents have been demanding more transparency about a spill last week of drilling mud into a river that the pipeline will cross.

From Seattle Times • Jul. 14, 2021

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

Roughly 42,000 gallons of drilling mud billowed across the tundra, and Itta started calling state and federal authorities to find out whether the town needed to evacuate.

From Washington Post • Dec. 12, 2019

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

In addition to the Calumet transaction, two years ago Anchor bought an Ohio firm that grinds barite used as a component in drilling mud.

From Washington Times • Oct. 26, 2014