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

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

On June 10, about 40 gallons of drilling mud oozed out of the ground outside Mingo Presbyterian Church, a 187-year-old building with a bright red roof next to the Seamans’ place.

From Washington Times • Oct. 27, 2018

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