mudstone

[muhd-stohn]

noun

Geology.

1. a clayey rock with the texture and composition of shale but little or no lamination.

mudstone

/ ˈmʌdˌstəʊn /

noun

1. a dark grey clay rock similar to shale but with the lamination less well developed

mudstone

1. A fine-grained, dark gray sedimentary rock consisting primarily of compacted and hardened silt and clay, similar to shale but without laminations. The proportions of silt and clay in mudstone are approximately equal.

Word History and Origins

Origin of mudstone¹

First recorded in 1730–40; mud + stone

Example Sentences

They are about 3.5bn years old and are a type of rock called mudstone, which is fine-grained rock formed from clays.

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The specimen, which Dr. Glasspool discovered in a mudstone from southern Wales, is one of many pieces of ancient charcoal that have been studied in recent years to explore how fires burned in the past.

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These layers have mouth-watering names that sound like expensive paint colors or elaborate pastries: Valmonte Diatomite, San Onofre Breccia, and the PV specialty, Malaga Mudstone.

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The name she picked aligns with other rock types, like sandstone, mudstone, and limestone.

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Riedman returned to the United States with shale and mudstone: remnants of an ancient coastal ecosystem that alternated between shallow, subtidal mudflats and coastal lagoons.

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