rock flour

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Related to rock flour: Glacial flour

rock flour

Finely ground rock particles produced by glacial abrasion.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

rock flour

(Geological Science) very finely powdered rock, produced when rocks are ground together (as along the faces of a moving fault or during the motion of glaciers) and are thus chemically unweathered

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References in periodicals archive ?

Geologists say their shimmering hues are caused by sunlight refracting against glittering silt-sized rock flour constantly deposited at the lake bed by thundering waterfalls.

Banff offers a walk in the clouds

The spring freshet, when winter snow and ice melt, releases a deluge of water that sweeps soil, rock flour, and plants into the river channel and dumps all of the previous year's debris into the ocean.

Of the river & time: flowing waters run deep with evidence of earth's mountains and climate

The hard rock is mainly granodiorite with size of individual pieces ranging from few centimeters to tens of meter, whereas, fine matrix primarily consists of rock flour with traces of silt and clay.

Geotechnical aspects of Attabad landslide dam

Proposals have included a cushion of air, lubrication by water or by rock flour or a thin melted layer.