silt

views updated May 23 2018

silt / silt/ • n. fine sand, clay, or other material carried by running water and deposited as a sediment, esp. in a channel or harbor. ∎ a bed or layer of such material. ∎ technical sediment whose particles are between clay and sand in size (typically 0.002–0.06 mm).• v. [intr.] become filled or blocked with silt: the river's mouth had silted up | [as n.] (silting) the silting of the river estuary. ∎ [tr.] fill or block with silt.DERIVATIVES: sil·ta·tion / silˈtāshən/ n.silt·y adj.

The Oxford Pocket Dictionary of Current English

Silt

views updated May 18 2018

Silt

A soil separate consisting of particles of a certain equivalent diameter. The most commonly used size for silt is from 0.05 to 0.002 mm equivalent diameter. This is the size used by the Soil Science Society of America and the U.S. Department of Agriculture , but others recognize slightly different equivalent diameters. As compared to clay (less than 0.002 mm), the silt fraction is less reactive and has a low cation exchange capacity. Because of its size, which is intermediate between clay and sand, silt contributes to formation of desirable pore sizes, and the weathering of silt minerals provides available plant nutrients. Wind-blown silt deposits are referred to as "loess."

Environmental Encyclopedia

silt

views updated May 17 2018

silt XV. of uncert. orig.; perh. — a Scand. word repr. by Norw., Da. sylt, Norw. and Sw. dial. sylta salt marsh, sea beach, corr. to OLF. sulta (LG. sulte, sülte; Du. zult), OHG. sulza (G. sülze) salt marsh, salt pan, brine, f. Gmc. *sult- *salt- SALT.

The Concise Oxford Dictionary of English Etymology T. F. HOAD

silt

views updated May 08 2018

silt
1. In the commonly used Udden—Went-worth scale, particles between 4μm and 62.5 μm in size. Other classifications exist. In pedology, silt refers to mineral soil particles that range in diameter from 0.02 to 0.002 μm in the international system, or from 0.05 to 0.002μm in the USDA system. See PARTICLE SIZE.

2. A class of soil texture.

A Dictionary of Earth Sciences AILSA ALLABY and MICHAEL ALLABY

silt

views updated May 29 2018

silt
1. In geology, according to the most widely used (Udden–Wentworth) scale, particles between 4 μm and 62.5 μm in size.

2. In pedology, mineral soil particles that range in diameter from 0.02–0.002 μm in the international system or 0.05–0.002 μm in the USDA system.

3. A class of soil texture.

A Dictionary of Ecology MICHAEL ALLABY

silt

views updated May 23 2018

silt
1. Mineral soil particles that range in diameter from 0.02–0.002 μm in the international system or 0.05–0.002 μm in the USDA system.

2. A class of soil texture.

A Dictionary of Plant Sciences MICHAEL ALLABY

silt

views updated Jun 11 2018

silt Mineral particles produced by the weathering of rock. These particles, varying in size between grains of sand and clay, are carried along in streams and rivers, to be deposited in the gently flowing lower reaches of rivers. When the river overflows its bank, the silt deposit forms fertile land.

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