boulder clay

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

Origin of boulder clay

First recorded in 1855–60

Probably some may have been derived, as Wahnschaffe has suggested, from denudation of boulder-clay.

Fragments of Earth Lore |James Geikie
Mr. Mackintosh refers to the so-called “stratification” of the boulder-clay, as if that were a proof of accumulation in water.

Fragments of Earth Lore |James Geikie
That there might be several deposits of the boulder-clay with intervening strata, does not appear to have been suggested.

Prehistoric Man |W. L. H. Duckworth
Rough tors and crags are smoothed off, while boulder-clay nestles on the lee-side.

Fragments of Earth Lore |James Geikie

The climatic reasons for the supposition that the boulder-clay is a marine deposit have already been given (p. 66).

The History of the European Fauna |R. F. Scharff

boulder clay

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