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

Melissa Lorentz, an attorney with the Minnesota Center for Environmental Advocacy, said Enbridge’s permits specifically prohibit the discharge of drilling mud into waters along the route.

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

He graduated, decided coaching wasn’t his calling and instead went to work in New Orleans as a drilling mud engineer.

From Washington Times • Oct. 26, 2014