Granulometric Composition

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Granulometric Composition


the content of granules of varying size in rock, soil, or an artificial product, expressed as a percentage of the bulk or of the quantity of granules of the examined sample.

The granulometric composition is an important indicator of the physical properties and structure of a natural or artificial material. Depending upon the research purpose, the granulometric composition can be determined with a varying degree of detail. There is no generally accepted classification for the data of granulometric composition, and this is due to the differing purposes and objects for which the granulometric composition is determined. In geology (lithology), pedology, marine geology, and in technology (abrasives and the dressing of minerals) there are special classifications and names of the granulometric fractions. Thus, in sedimentary rock, the categories are large boulders, over 500 mm; medium-sized boulders, 500–250 mm; small boulders, 250–100 mm; pebbles. 100–10 mm; large gravel, 10–5 mm; small gravel, 5–2 mm; coarse sand, 2–1 mm; large sand, 1–0.5 mm; medium sand, 0.5–0.25 mm; fine sand, 0.25–0.10 mm; silt, 0.10–0.05 mm; dust, 0.05–0.005 mm; and clay, less than 0.005 mm.

The granulometric composition is determined by using granulometric analysis (granulometry). Determining the granulometric composition of fragmentary rock is essential forjudging the rock’s reservoir properties and for discovering under what conditions the rock was formed. The granulometric composition of ground makes it possible to judge its technical properties for construction purposes, while the granulometric composition of soils makes it possible to determine their structural features, which to a significant degree determine soil fertility.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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The experiment was established on medium heavy mixed rendzina soil derived from chalk rock, with the granulometric composition of loam.
The following variables were evaluated: pH; Al, Ca, Na, K, and P (exchangeable) contents; cationic exchangeable capacity (CEC); coarse fraction (pebbly and gravel); granulometric composition (coarse sand, fine sand, silt, clay, and flocculation degree); organic carbon; and nitrogen.
Clam distribution was analyzed along a 32 km coastal fringe whose granulometric composition varies from very fine to coarse sand.
The first one is sand the granulometric composition of which was determined according to the requirements of LST EN 933-1:2002.
Experimental research on influence of granulometric composition on sandy soil strength and reological properties, EJGE 18: 4081-4091.
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Soil horizons are heterogeneously different in granulometric composition. Dark humus horizon is clayey, clayey-illuvial horizon is light-clayey and the transitional to the rock is clayey [8].
Granulometric composition of such clay is presented in Table 2.