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

With the exception of foraminifera which have been found in the boulder clay of widely separated regions, fossils are practically unknown; but in some maritime districts marine shells have been incorporated with the clay.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 3 "Borgia, Lucrezia" to "Bradford, John" by Various

The glacier that lodged it there, also rounded the granite dome in Central Park and scattered the rock-strewn boulder clay on Long Island.

From Earth and Sky Every Child Should Know Easy studies of the earth and the stars for any time and place by Rogers, Julia Ellen

Farther east where the two tracks of the New York and New England railroads converge, a cut shows a section of at least 40 feet of boulder clay.

From Drainage Modifications and Glaciation in the Danbury Region Connecticut State of Connecticut State Geological and Natural History Survey Bulletin No. 30 by Sawyer-Harvey, Ruth

I can now, however, entertain little doubt that it belonged to the boulder clay period of submergence, and that the fauna with which it was associated bore the ordinary sub-arctic character.

From My Schools and Schoolmasters or The Story of my Education. by Miller, Hugh