boulder clay

American  

noun

Geology.

1. a glacial deposit consisting chiefly of unstratified clay with embedded boulders.

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boulder clay British  

noun

1. an unstratified glacial deposit consisting of fine clay, boulders, and pebbles See also till 4

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Etymology

Origin of boulder clay

First recorded in 1855–60

Example Sentences

Happisburgh, home to about 1,100 people, is so susceptible to erosion because the cliffs are made from boulder clay which slumps when wet.

From BBC • Dec. 30, 2022

Lyell visited Kinnordy from time to time between 1817 and 1824, and found on his father's estate and other localities in Strathmore a number of small lakes, lying in hollows of the boulder clay.

From The Coming of Evolution The Story of a Great Revolution in Science by John W.

The largest transported mass occurs at Linksfield, where a succession of limestones and shales rests on boulder clay and is covered by it, which from the fossils may be of Rhaetic or Lower Lias age.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" by Various

This boulder clay covers almost all the low ground north of the Thames Basin, its southern margin fading away into washed sands and gravels.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 4 "England" to "English Finance" by Various

And this boulder clay, as Mr. Jukes Brown further observes, has forced its way up the sides of the chalk, in places, to a height varying from 300ft. to 400ft.

From Records of Woodhall Spa and Neighbourhood Historical, Anecdotal, Physiographical, and Archaeological, with Other Matter by Walter, James Conway