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

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

Even if the drilling mud was primarily clay, Matteson said, the silt can still harm sensitive aquatic organisms.

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

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